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installation, operation, and maintenance manual

1. TEFC Recommendation See following note Bronze sleeve bearings All 1 phase motors Fractional HP ODP TEFC or TEAO Century G E or equal Recommendation See following note Fractional HP Century Bronze sleeve single phase or equal bearings ODP or TEFC Recommendation See following note Dampers Factory Sleeve or equal Hecommendation See following note 18 1 Blower Motors Some motors require lubrication while others do not Those that require lubrication can be identified by the presence of grease plugs in the motor casing at each end Motors that do not have grease plugs cannot be greased and are lubricated for the life of the motor bearing Lubrication of motors should be done while the mo tor is warm and at a standstill Remove and clean all grease plugs and insert a grease fitting in the upper hole in the motor casing at each end Viewed as if motor were sitting horizontally on its base There may be one or two plugs in each end casing of the motor Add a small amount of a clean good grade ball bear ing grease such as Exxon Polyrex EM or equal with a low pressure grease gun Run the motor five minutes before removing the grease fittings and replacing the plugs CAUTION An excess of grease will overheat the bearings NOTE On totally enclosed fan cooled TEFC motors the rear end fan housing must be removed to expose the grease plugs 2 Dampers
2. ALL LIFTING LUGS PROVIDED MUST BE USED WARNING To insure that a proper unit lift is made lift unit approximately 24 inches and verify proper center of gravity lift point To avoid dropping of unit reposition lifting point if unit is not level Failure to properly lift unit could result in death or serious injury or possible equipment or property only damage A spreader bar must be used to span over the unit for each pair of lifting lugs provided in order to avoid over stressing and damaging the unit s structure Position the unit over the roof curb platform or mounting pad and slowly lower into place Once the unit is in place carefully remove lifting cables and spreader bars Do not allow the crane s hook the spreader bars or lifting cable to fall on the unit B Locating the Unit Prior to locating the unit authorities having jurisdic tion should be consulted before installations are made Approval permits should be checked against the unit received If in doubt regarding the application of this appliance consult the factory Locate the unit exactly level Special attention should be given to the duct electrical water and fuel con nection points The minimum clearance to combustible material must be maintained as listed in Table 1 Table 1 Minimum clearance to combustible material also consult local codes and regulations Clearances to Combustible Material Horizontal Units Front 3
3. Dampers should be inspected monthly daily in icy or snowy weather for securely fastened linkages and smooth operation If dampers are binding or excessively noisy then lubrication may be required Place one drop of 420 wt machine oil on each blade bearing and linkage ball joint Do not over lubricate and wipe any excess from the area Be sure to note that dampers over 49 inches long have intermediate bearings which require lubrication On outdoor models with factory supplied discharge dampers you will need to remove the top cover to access the damper bushings Replace cover and caulk as necessary C Air Filters All filter banks should be equipped with a manometer or differential pressure switch to indicate when the filters are dirty Filters should be replaced when the differential pressure across them reaches the manufacturer s recommended final value Dirty filter elements should be replaced with a clean element of the same type and size In addition the factory not only suggests but insists that air filters be checked every 30 days daily in icy or snowy weather and replaced with new filters throw away type or cleaned washable type as required Cleanable filters should be given new application of filter coating after washing to maintain optimum filter performance The frequency of cleaning and replacing air filters applies twelve months of the year where blowers are used for year round ventilation D Evaporative Me
4. d _ ELECTRICAL DEMAND AND USAGE MONITORING A current transducer monitors the instantaneous amp draw of all loads in the unit and inputs that information to the DDC controller via a 4 20 mA DC signal The control program multiplies the instantaneous amp draw by the unit design voltage to calculate the instantaneous demand in kilowatts KW Cumulative electrical usage is calculated by multiplying the instantaneous demand by the unit runtime The DDC controller retains the following information in memory and stores the data as BACnet readable points contact factory for Aztec DDC Points List e Instantaneous Demand kW e Peak Demand Today kW e Peak Demand Yesterday kW Peak Demand Month to Date kW e Peak Demand Last Month kW e Peak Demand Year to Date kW e Peak Demand Last Year kW e Usage Today kWh e Usage Yesterday kWh e Usage Month to Date kWh e Usage Last Month kWh e Usage Year to Date kWh e Usage Last Year kWh A reset function is provided on the ELECTRICAL DEMAND branch of the BACview menu tree to allow the operator to reset all electrical usage and demand data to zero Usage and demand data cannot be recovered once they are purged from the system via reset COMFORT INDEX AND SATISFACTION RATING The Comfort Index Cl and Satisfaction Rating SR features of the control program allow the operator to make an at a glance assessment of unit performance via the BACview Comfort Index The DDC controller calculates the
5. 12 Universal Inputs UI 01 Ul 12 Inputs 1 amp 2 o Pulse e Inputs 1 12 o Thermistor RTD 4 20mA o 0 10VDC 6 Binary Outputs e Relay contacts rated at 5A Resistive 9 250VAC LED indication Network Communication 6 Analog Outputs e Outputs 1 2 4 20mA o 0 10VDC e Outputs 3 6 o 0 10VDC mdi Output Assignments Analog AO 1 Damper Control AO 2 Supply Fan VFD Control AO 3 Cooling Tower VFD Control AO 4 DA Temp Control Output Assignments Digital BO 1 Supply Fan Start Stop BO 2 Clg Stg 1 Pump Start Stop BO 3 Clg Stg 2 Pump Start Stop BO 4 Cooling Tower Fan Start Stop BO 5 Clg Stg 1 Fill Drain Start Stop BO 6 Clg Stg 2 Fill Drain Start Stop Input Assignments Universal UI 01 Supply Air Temperature Sensor UI 02 Outside Air Temperature Sensor UI 03 o Non multiplexed 1 stage units Clg Stg 1 Float Switch o Multiplexed 2 stage units Clg Stg 1 Float Switch Clg Stg 2 Float Switch UI 04 Mixed Air Temperature Sensor UI 05 Not used at this time UI 06 Building Pressure Transducer UI 07 Clogged Filter Status UI 08 Supply Fan Status UI 09 100 Outside Air Enable UI 10 Auxiliary Unit Enable UI 11 Current Transducer Ul 12 Humidity Transducer Input Assignments Rnet RNET Room Air Temperature Sensor APPENDIX III Flex 6126 Controller Battery Checkout The battery on the unit control module retains the controller s memory in the event of power failure The 10 year Lithium CR2032 bat
6. 19 Depending on local water pressure a pressure regulating valve may be required to stabilize the make up water flow and the operation of the water fill and level control valve in the unit s indirect evaporative section and if provided the direct evaporative section This equipment has been tested prior to shipment However during transit control setpoints can change and wiring can come loose Do not assume controls are defective until all associated setpoints and wiring are checked If you do not have the optional BACview 6 KP 01 keypad display it will be difficult to troubleshoot any alarm that may occur on the unit To reset most alarms on the FLEX 6126 Controller UC 01 without a BACview 6 keypad display simply turn the power off and back on at the unit disconnect If you have a BACview 6 keypad display the alarm can be reset remotely or at the FLEX 6126 Controller Suggested Tools and Instruments Volt Ohm Meter Thermometer Tachometer Ammeter Manometer 0 10 W C Microammeter Standard Hand Tools D C Volt Meter Refrigeration Gauges if applicable BACview 6 SECTION V UNIT START UP Before attempting to start the unit read and under stand the sequence of operations and electrical schematic and the Burner IOM if applicable WARNING During installation testing servicing troubleshooting of this product it may be necessary to work with live electrical components Have a qualified licensed
7. 40 F 130 F Unocc Zone Stpt 40 F 130 F Supply Air Temp Stpt 40 F 130 F Min Sup Air Temp Stpt 55 F 130 F Max Sup Air Temp Stpt 55 F 130 F Freezestat Stpt 35 F 80 F Sup Fan VFD Min Speed 5 100 Clg Twr VFD Min Speed 5 100 Reset Stage 1 Counter No Yes Stg 2 Interstage Differential 2 F 10 F Reset Stage 2 Counter No Yes Drain Twr Sump based on p Runtime Schedule Drain Stg 1 p at r o clock 24hr p Mon Tues Wed Thurs Fri Sat Sun r 0 23 o clock Drain Stg 1 after p hrs of runtime for r minutes p 0 99 hours r 0 999 minutes Drain Stg 2 p at r o clock 24hr p Mon Tues Wed Thurs Fri Sat Sun r 0 23 o clock Drain Stg 2 after p hrs of runtime for r minutes p 0 99 hours r O 999 minutes OA Temp to Drain Sump s 35 F 80 F Bldg Pressure Stpt 0 100 W C 0 100 W C Mixed Air Temp Stpt 30 F 90 F Econ Enable OAT lt p p 50 F 90 F e OAH lt r RH r 0 100 OA Damper Min Open 0 100 Damper Open Stpt 0 100 Alrm Config Prev Home Sched Overrides 43 MENU SELECTION TREE FOR BACVIEW continued Unit Status HOTKEY 4 The Status Menu always displays the current status of the fan and cooling Zone Temp Supply Air Temp Mixed Air Temp Bldg Pressure OA Humidity OA Temp
8. 7 Sunday Cooling Stage 1 Fill Drain Duration 15 minutes Unrestricted Cooling Stage 2 Fill Drain Duration 15 minutes Unrestricted Cooling Stage 1 Drain Time 1 1 1 00 AM use 24 hour format Cooling Stage 2 Drain Time 2 2 2 00 AM use 24 hour format Cooling Stage 1 Runtime Drain Trip 100 hours Unrestricted Cooling Stage 2 Runtime Drain Trip 100 hours Unrestricted Cooling Stage 1 Maintenance Alarm Enable No No Yes Cooling Stage 2 Maintenance Alarm Enable No No Yes Cooling Stage 1 Maintenance Alarm Trip 2 200 hours Unrestricted Cooling Stage 2 Maintenance Alarm Trip 2 200 hours Unrestricted Temperature Setpoints ITEM DEFAULT RANGE Unoccupied Zone Setpoint 100 F 40 F 130 F Occupied Zone Setpoint 73 F 40 F 130 F Cooling Economizer Setpoint 55 F 40 F 130 F Supply Air Temperature Setpoint 70 F 40 F 130 F Cooling Stage 2 Interstage Differential 2 F 2 F 10 F Minimum Supply Air Temperature Setpoint 55 F 55 F 130 F Maximum Supply Air Temperature Setpoint 75 F 55 F 130 F Mixed Air Temperature Setpoint 55 F 30 F 90 F Freezestat Setpoint 45 F 35 F 80 F Outside Air Temperature to Drain Sump s 36 F 35 F 80 F Economizer Configuration ITEM DEFAULT RANGE Outside Air Temperature for Economizer 65 F 50 F 90 F p E s 40 F 130 F Pressure Setpoints ITEM DEFAULT RANGE Building Pressure Setpoint 0 00 W C 0 100 W C 0 100 W C 24 D
9. OA Enthalpy OA Damper Open 10096 OA Contact Filter Status Supply Fan Command Supply Fan Status Supply Fan VFD Output Clg Twr Fan Command Clg Twr Fan Output Clg Stg 1 Pump Clg Stg 1 Fill Drain Clg Stg 1 Starts Clg Stg 1 Runtime Clg Stg 2 Pump Clg Stg 2 Fill Drain Clg Stg 2 Starts Clg Stg 2 Runtime Elect Usage Cmfrt Indx Prev Home Alarm Stpt Unit Resets HOTKEY 6 Clg Stg 1 Starts Reset Clg Stg 1 Runtime Reset Clg Stg 2 Starts Reset Clg Stg 2 Runtime Reset Electrical Usage Demand Reset Satisfaction Rating Timers Reset Alarms Reset Alarms HOTKEY 1 Unit Command Unoccupied Occupied F F F W C rh F btu lb m Off On Clean Dirty Off On Off On Off On Off On Off On hours Off On Off On hours Off On Off On Off On Off On Off On Off On Off On e Module Event History 100 Most Recent Active Alarms Active Faults Returned To Normal Manually Cleared Previous Alarm Configuration ITEM VALUE UNITS RANGE Clg Stg Maint hours 0 9999 hours Alarm Trip Cig Stg Maint hours 0 9999 hours Alarm Trip Use Clg Stg 1 Maint Alarm Off default Off On Bee Clo 592 Off default Off On Maint Alarm Schedule HOTKEY 7 e 24 hr Operation Daily Schedule1 typical 1 through 4 Use Start Time Stop Time DAYS Previous Next Home L
10. On Off events with any combination of days The daily schedule sets the typical On Off times for the unit The holiday schedule can be programmed for up to 12 separate On Off events with any combination of days The holiday schedule sets the Off times for holidays and other shutdown periods The override schedule can be programmed for up to 2 separate On Off events with any combination of days The override schedule sets the On times that will override the holiday schedule This scheduling system allows the user to program a diverse array of On Off operations The Aztec DDC system has no preset operational schedule 25 UNIT OPERATING MODES continued To set the operational times of the unit scroll through the SCHEDULES menu tree and locate the desired Daily Holiday or Override branch Enter the days and times for the unit to operate In the Daily or Override section these times should correspond to the desired on times for the unit s operation In the Holiday section these times should correspond to the desired off times for the unit s operation For any schedule to function the Use tab must be set to yes To set the time clock function for 24 hour continuous operation scroll through the menu tree and locate the SCHEDULES page Set the 24 Hr Operation to yes Enter the Daily section of the menu and set the Use tab to yes Finally select the days for 24 hour operation See the CLOCK SET section of this manual for s
11. WARNING Failure to comply with the general safety information may result in extensive property damage severe personal injury or death Periodic maintenance is essential to the efficient operation and extended service life of this equipment Failure to provide maintenance as recommended may void the equipment warranty A Maintenance Schedule 1 Daily a Check gauges monitors instruments and equipment settings 2 Monthly a Check all set screens on fan and motor assemblies b Check all valves piping and connections for leaks c Inspect filters and pump screens Clean or replace as necessary d Check all dampers damper actuators and linkages Adjust lubricate and tighten if necessary e Ensure that there are no obstructions blocking the air supply or discharge to the unit f Inspect the area and make sure that no combustible or hazardous material has been stored within the clearances shown on the unit nameplate g Check and clear all air sensing tubes and fittings CAUTION To prevent damage to the unit remove tubes from switches and transducers before using compressed air to blow through tubing 3 Quarterly a Complete the monthly maintenance schedule b Check voltages and amp draw on main fan motor c Check the operation of all safety controls individually d Check that the battery in UC 01 has 3 VDC Do not remove or replace battery with the power turned off to the control e Inspect all evaporative m
12. maintenance schedule Conduct any required maintenance to ensure continued efficient operation of the unit This includes following the procedure in the IOM Manual for removing mineral deposits from the evaporative media and checking the piping for leaks as well as ensuring that all electrical components are operating correctly and that wires are connected securely to the correct terminals Reset the alarm hotkey FN MUTE on the BACview BACview The BACview is a four line by forty character display used to change setpoints and monitor the unit s operation Cooling Stage 1 The first stage of cooling is the indirect cooling coil GLOSSARY PID loop Proportional Integral and Derivative loops are a common control scheme used in modulating HVAC systems WebCTRL web based graphical user interface that provides the user access to the unit via the internet Cooling Stage 2 The second stage of cooling is the direct evaporative media cdi MENU SELECTION TREE FOR BACVIEW This section will assist the user in navigating the menu functions of the control program For convenience Hotkeys are provided to allow the user to jump directly to a specific menu heading Simply press and hold the FN key While holding the FN key press the number key of the desired menu and it will appear The number key associated with the menu heading is shown below Links to other menu headings are also availab
13. the Aztec DDC controller outputs a 0 5 VDC signal from AO 4 supply air temperature control output which is then input to the IFD DDC controller at IN 1 The IFD DDC controller then outputs 0 10 VDC to the modulating gas valve motor to control the burner For Aztec units equipped with an IFD 800 or 1120 the Aztec DDC controller outputs a 0 10 VDC signal from AO 4 which is then input directly to the modulating gas valve motor to control the burner Based on the duct furnace size the controller outputs the maximum 5 or 10 VDC as described in the preceding paragraphs in this section from AO 4 when the supply air temperature is 2 F below the supply air temperature setpoint The controller modulates the output downward to 0 VDC as the supply air temperature increases to 2 F above the supply air temperature setpoint Refer to the IFD Series Duct Furnaces Installation Operation and Maintenance Manual for detailed information about duct heater operation 26 DIAGNOSTICS CRITICAL ALARMS This section should assist the user in troubleshooting critical alarms that have been displayed on the BACview These faults require the operator to correct the condition and reset the alarm before normal unit operation resumes Alarm Cause Remedy A Freeze Alert 1 Low supply air temperature 2 Sensor circuit or the sensor itself is shorted 3 Sensor circuit or the sensor itself is open 1 Wait for the supply
14. 2 Variable Frequency Drive FD 01 2 Check VFD for faults and or RE 33 and fan is not running enabled 3 Air flow switch is open 3 Check for proper airflow Adjust and or replace switch 4 Cooling Changeover and or Econ 4 Change to correct setpoints See omizer Setpoints not set correctly sequence of operation 5 BO 2 and or BO 3 are not 5 See sequence of operation energized D Cooling relays RE 1 Cooling relays RE 34 and or 1 Check and or replace 34 and or RE 33 RE 33 are not closed are energized and 2 Cooling relays RE 34 and or 2 Correct wiring condensing unit or chiller RE 33 contacts are not wired are not on if applicable correctly 3 Compressors or chiller water pump 3 See Troubleshooting Guide provided is not running with condensing section or chiller E Unit s discharge air flow 1 Unit s supply air inlet filters are 1 Clean or replace filters rate has decreased or is blocked or dirty below nameplate rating 2 System s external static pressure has 2 Correct or contact factory repre increased or is higher than specified sentative 3 Building s exhaust fans are not 3 Power up exhaust fans or correct operating or building s relief relief opening size openings are not properly sized 4 Direct evaporative cooling media is 4 Clean or replace media as required does not operate or being recirculated is not the volume of water 3 sufficient 4 defective Customer interl
15. Comfort Index using the ratio of the absolute value of the zone temperature MRT Expert or supply air temperature MDT Expert minus the zone or supply air temperature setpoint to the zone or supply air temperature setpoint or SA temperature zone or SA temperature setpoint CI 1 x 100 zone or SA temperature setpoint For example in an MRT Expert system if the zone temperature is 75 F and the zone temperature setpoint is 73 F the Comfort Index would be as follows 175 F 73 F cr E 100 97 396 73 F As the zone or supply air temperature approaches the zone or supply air temperature setpoint the Comfort Index will increase reaching 10096 when the temperature equals the setpoint Satisfaction Rating The DDC controller calculates the Satisfaction Rating as the ratio of the satisfied runtime to the total unit runtime The satisfied runtime is defined to be the amount of time during which the zone temperature is less than or equal to the zone temperature setpoint plus 2 MRT Expert or the supply air temperature less than or equal to the supply air temperature setpoint plus 10 F MDT Expert SR time 100 For example if the zone or supply air temperature has been below the zone or supply air temperature setpoint for 1337 hours and the unit has been on for 1400 hours the Satisfaction Rating would be as follows 1337 hours SR x 100 95 5 1400 hours Periodically check th
16. F and is user configurable via the BACview the cooling stage 1 and 2 fill drain binary outputs BO 5 and BO 6 will de energize and the fill and drain valves will return to their normally closed and normally open positions respectively The sump s will drain The Cooling Stage 1 and 2 Water Level Failure alarms will be disabled The DDC controller will neither re energize the binary outputs nor re enable the alarms until the outside air temperature rises 5 F above the OA Temp to Drain Sump s setpoint Manual Override The administrator password for the BACview is required in order to use the manual overrides The off on state of the fill and drain outputs BO 5 and BO 6 can be controlled manually via the OVERRIDES branch of the BACview menu tree to induce manual fill and drain cycles Toggle the Lock Stg 1 F Drn BO5 field to ON fill or OFF drain to force the cooling stage 1 fill and drain output on or off depending on the desired state To enable this change and lock the output in the desired state toggle the No Yes field from NO to YES Once any manual fill drain cycles are complete unlock the outputs by toggling the No Yes field of the binary output from YES to NO The same process can be repeated for the stage 2 fill and drain output BO 6 WARNING Manually overriding these binary outputs disables all automatic fill and drain functions described in this section and could result in severe damage to the equipment
17. Please Note This equipment has been tested and inspected It has been shipped free from defects from our factory However during shipment and installation problems such as loose wires leaks or loose fasteners may occur It is the installer s responsibility to inspect and correct any problems that may be found TEC 4830 Transport Drive Dallas TX 75247 Phone 214 638 6010 gt Evaporative Units www aztec server cooling com SECTION I FOREWARD As is the case with any fine piece of equipment care must be taken to provide the proper attention to the operation and maintenance details of this machine This manual along with the burner IOM if applicable has been prepared in order for you to become well acquainted with those details and in doing so you will be able to give your Indirect or Indirect Direct Evaporative Cooling System the care and attention which any piece of equipment needs and deserves It is the customer s and installation personnel responsibility to determine if the unit is equipped with all of the safety devices required for the particular application Safety considerations include the accessibility of the unit to non service personnel the provision of electrical lockout switches maintenance procedures and automatic control sequences Clearly mark all emergency shutoff devices Table of Contents Section I Foreword Table of Contents and Important Notice 2 Sec
18. Rating Reset SR Timers Prev Home Overrides HOTKEY 8 Binary Outputs e Lock Stg 1 Pump BO2 LockStg2 Pump e Lock Stg 1 Fl Drn BO5 LockStg2 Fl Drn BO6 e Analog Outputs e Lock Damper AO1 Lock SF VFD AO2 e Lock CT VFD AO3 e Keypad e Prev e Keypad e Status 45 Off On No Yes No Yes No Yes No Yes 96 No Yes 96 No Yes 96 No Yes APPENDIX I 10 000 Ohm Thermistor Output Curve Resistance Ohms Typical 10 000 Ohm Thermistor Output Curve 22 4 14 32 41 50 59 68 77 86 95 104 113 122 131 140 149 Temperature in Degrees F Resistance Ohms Typical 10 000 Ohm Thermistor Output Curve 30000 25000 20000 15000 10000 5000 Temperature in Degrees F 46 APPENDIX Il Flex 6126 Controller Specifications Power Requirements 24VAC 1096 20VA 26VA with BACview attached Network Communication BACnet ARCNET and MS TP Modbus RTU or N2 bus at up to 76 8K baud or 156K baud over ARCnet LonWorks and Ethernet using plug in communications board User Interface Modulating room temperature control with intelligent room sensor and BACview LCD control panel Memory 1MB of flash memory and 1MB of non volatile battery backed RAM Realtime Clock Battery backed to keep time in the event of power failure Temperature Operating Range 20 F to 140 F 10 to 95 RH non condensing Inputs Outputs
19. and is intended as a guide only You might also need to reference the Burner IOM if applicable Fan and Cooling Mode WARNING Many of the steps listed on the following pages require electrical cabinet and blower access while the unit is powered High voltage and moving parts are present and these steps should be performed by qualified service personnel If any of the controls requir ing manual reset were at fault this is an indica tion of a problem with the system that should be investigated Symptom Cause Remedy A Supply air fan or cooling Low or no voltage k Check power source tower exhaust fan does 2 Circuit breaker open or fuse s 2 Check and replace not operate blown 3 Customer interlock not closed or 3 Close or connect customer inter connected lock 4 Fan is disabled 4 Enable the fan 5 Field installed controls open 5 Check field installed controls for proper settings 6 Freeze protection Low Discharge 6 See sequence of operations Temperature tripped 7 BO 1 on UC 01 not energized if 7 See sequence of operations applicable 8 BO 4 on UC 01 not energized 8 See sequence of operations 9 Damper motor not operating it s 9 Check for power at damper motor end switch is not making or the and that end switch has been wired damper is binding correctly to the N O normally open contact Check that the link age is clear and not binding 10 Overload Prot
20. and setting the unit use the lifting lugs provided as shown in Drawing C000737 or move the equipment on rollers Hooks jacks or chains must not be used around the casing main control panel or exterior mounted controls During transit unloading and setting of the unit bolts and nuts may have become loosened It is recom mended that all nuts and set screws be tightened Turn fan shaft by hand to make certain that blower does not rub against blower housing and that set screws are tight If units are not set immediately cover all open ings that might be exposed to the weather Open the cover on the electrical control box located on the unit Inspect all wire terminals and wiring termina tions to ensure that all connections are tight Rotate fans monthly IMPORTANT Lift and install the modules or sec tions of a unit separately Flange connections pro vided between modules or sections are not struc tural and damage will occur if any attempt is made to lift modules that have been flanged together See the specification sheet and submittal drawing for unit or section weight and to determine proper orientation for each section When unloading sections and or units or moving equipment to its final location exercise care to avoid distortion Lift sections and or units only by the lifting lugs provided and follow the procedures as outlined below RIGGING AND MOUNTING DATA INDIRECT OR INDIRECT DIRECT EVAPORATIVE COOLING UNITS
21. before wiring unit Failure to do so may result in personal injury or death from electrical shock WARNING Controls must be protected from water Do not allow water to drip on the ignition system NOTE Before installing any wiring check the unit rating plate for supply power rating All electrical connections must conform to the current edition of ANSI NFPA No 70 National Electrical Code and applicable state and local codes Since shipment of unit may require disassembly after factory check and test reconnection of some electrical devices will be required in the field Connect electrical wires supplied in factory furnished conduit to appro priate terminals All leads are tagged to facilitate field connections See wiring diagram provided with equip ment Complete all wiring to any optional accessories as shown on unit bill of material and electrical wiring diagram as required before applying voltage to the unit If damper actuators require field wiring make sure the gasket and cover are securely mounted and assembly is watertight Entry location for all field installed and control wiring is through the control panel If optional disconnect is not furnished with the unit the field provided disconnect must be of the proper size and voltage Refer to unit rating plate for minimum circuit ampacity and voltage The disconnect must be installed in accordance with Article 430 of the current edition of ANSI NFPA No 70 Nation
22. gt Home sClockSet LOGOUT gt Daily gt Prev 2 Navigate to the Daily field and press the Enter button The screen will show a blank daily schedule Daily Sch 1 Use NO Stat OFF 241 Start Time 0 0 Stop Time 0 0 DAYS MON Next gt Home LOGOUT gt Prev 3 To enable the Daily schedule set the Use field to Yes The Stat field indicates whether the schedule on that screen is currently active so you may see either ON or OFF in this field Navigate to the Start Time field and set the start time for 6 00 AM Be aware that times are programmed in a 24 hour format For example 2 00 PM would be programmed as 14 00 which will show up on the BACview screen as 14 0 4 Navigate to the Stop Time field and set the stop time for 5 00 PM 17 00 in the 24 hour format 5 Navigate to the Days fields making sure the cursor surrounds the first hyphen Press the Enter button and then press the link key that corresponds to INCR on the screen The field will now show MON indicating that this schedule will be active every Monday from 6 00 AM to 5 00 PM Repeat this process for each of the remaining Days fields except for SAT and SUN Your screen should now look like this Use YES Stat 24hr Stop Time 17 0 THU FRI Home LOGOUT Daily Sch 1 Start Time 6 1 0 DAYS TUE WED Prev Next 6 The week of Thanksgiving for 2012 is from Sunday No
23. selected When Off is selected by the cursor it will appear on the screen surrounded by brackets 3 Press the ENTER button Off will flash on the Screen indicating that this value is now editable Use the link keys corresponding to INCR and DECR to scroll through the available parameter values which are Auto Off and Manual Set the value of the parameter to Manual and press the ENTER button 4 Once the system has accepted this new parameter value the unit will run continuously in Manual mode Modstat The modstat module status screen allows the user to check the program version number and whether the programs are initialized and running If the red error LED is flashing on the module a modstat is a useful troubleshooting tool Perform the modstat by pressing and holding the FN key and then pressing the period key and then releasing both keys at the same time Scroll down until you see the following message 2 PRGs initialized 2 PRGs running If this message is not visible anywhere on the modstat screen after scrolling through the whole screen contact the factory to troubleshoot the issue with the unit control module There is likely an issue with the unit control module that is preventing the unit from functioning correctly The name of the main control program and its version number can also be seen on the modstat screen for example Application Software Version aztec6126 032813 For networking purpo
24. 6 inches Rear 6 inches Right 6 inches Left 6 inches Top 12 inches Floor 6 inches Consider control side as front of unit Optimum clearance for coil removal would be equiva lent to cabinet width Make a visual inspection to insure no damage has oc cured to the unit during installation C Curb Mounted Units Outdoor units can be supplied with an optional roof curb The curb greatly facilitates installation thereby reducing installation costs All connections to the unit duct piping electrical power and control wiring can be made through the roof opening The curb may be shipped prior to unit shipment curbs are shipped un assembled from the factory Use extreme caution in handling the curb Proper han dling and positioning will assure a water tight curb unit installation Re check approval prints prior to installation Be sure that there are no obstructions to ducting and that proper planning has been exercised in connection of piping and or electrical services The curb assembly may be bolted or welded to either trusses or roof decking however connection to roof trusses is recommended The curb is designed to carry the weight of the unit Additional support is required for certain applications Placement of the curb is critical in squareness and leveling Shims for leveling must be applied to the curb application of shims to the unit will tend to destroy the sealing effect after installation Make sure seali
25. ARCIS6 Ory 50 51 353 L Hr ae NH lt Sei 5 g zs amp de gt E y amp 49 2 5 Y K 49 d 22 20 gu en sug 8 m 2 iisiziissi A 19 2 9 3 52 NOTES 53 NOTES 54 NOTES 55 gt Evaporative Units 4830 Transport Drive Dallas TX 75247 Phone 214 638 6010 www aztec server cooling com
26. Air Temp Stpt and enter the desired temperature The allowable temperature range is 40 F 130 F To change the desired minimum supply or discharge air temperature scroll through the SETPOINTS menu tree locate the Min Sup Air Temp Stpt and enter a new temperature This temperature must not be greater than the Max Sup Air Temp Stpt The allowable temperature range is 40 F 130 F This sets the lowest discharge air temperature that will leave the unit To change the desired maximum supply or discharge air temperature scroll through the SETPOINTS menu tree locate the Max Sup Air Temp Stpt and enter a new temperature This temperature must not be less than the Min Sup Air Temp Stpt The allowable temperature range is 40 F 130 F This sets the highest discharge air temperature that will leave the unit If the maximum and minimum discharge temperature setpoints are set for the same temperature the supply air temperature will be the same as the setpoint regardless of the room temperature setpoint or actual room temperature 29 VARIABLE FREQUENCY DRIVE OPERATION The Aztec DDC system features a variable frequency drive VFD to control the main supply fan motor and an optional VFD to control the cooling tower fan motor The DDC controller modulates the speed of the main supply fan motor and cooling tower fan motor based on the unit modes as configured via the BACview Unless otherwise specified during ordering all units s
27. DC SYSTEM DEFAULT SETTINGS continued Outside Air Setpoints ITEM DEFAULT RANGE 96 Outside Air Setpoint 2096 096 100 Minimum Outside Air Setpoint 20 0 100 VFD Speed Setpoints ITEM DEFAULT RANGE Supply Fan VFD Minimum Speed 2596 596 100 Cooling Tower VFD Minimum Speed 5096 596 100 UNIT OPERATING MODES There are three different modes that control the unit operation e Off Manual e Auto There are also two different methods for controlling the operating modes e intelligent room sensor BACview panel with LCD display aninternet based WebCTRL interface or other 3rd party building automation system Controlling the operating modes is accomplished via the BACview panel KP 01 with LCD display A detailed description of the function of these modes follows MRT Expert Controls The Aztec MRT Expert modulating room temperature control provides full information regarding unit operation and allows the user to adjust all operational parameters using the BACview panel See the Menu Selection Tree for BACview section of this user manual for instructions that show how to change parameter values via the BACview AdaptAire units configured for MRT Expert controls will have a fixed discharge temperature of 70 F if the room temperature sensor is disconnected or otherwise fails to communicate with the unit control module Unit Off Mode Off Mode is the def
28. Finally select the days for 24 hour operation See the CLOCK SET section of this manual for setting the time date and Daylight Savings function See the MRT Expert Controls section of the manual for a step by step walkthrough guide that demonstrates how to program a schedule via the BACview interface Auxiliary Unit Enable The Auxiliary Unit Enable function overrides all other Auto Mode functions and cycles the unit into operation This function is activated whenever a contact is closed between terminals 229 and 230 on the unit s terminal strip located in the unit s main control panel Cooling functions use the Occupied Setpoints See the Typical Wiring Schematic section of this manual for more information This function can be used with a twist timer toggle switch door switch exhaust fan interlock or any other dry contact to override the time clock schedule The MDT EXPERT control does not support the night setback functions 28 VENTILATING AND COOLING OPERATING MODES The Aztec DDC controller automatically switches between the ventilating and cooling modes of operation The previous sections described the Cooling Setback operation This section concentrates primarily on the Occupied operating modes Ventilation Mode Ventilation Mode occurs when the fan is running but the unit is not providing cooling The ventilation mode is dependent on the room MRT Expert or outside air MDT Expert temperature relative to the r
29. INE VW 83 3 8 NPT N O SOLENOID VALVE FOR DRAINING INDIRECT COOLING COIL VW 84 3 8 NPT N O SOLENOID VALVE FOR DRAINING ADDITIONAL INDIRECT COOLING COIL ONLY EQUIPPED ON LARGER SIZE UNITS W 85 1 OR 1 1 2 NPT N O SOLENOID VALVE FOR DIRECT SUMP DRAIN LINE NOTES A ORDER OF CONNECTIONS SHOWN IN THIS DIAGRAM MAY NOT CORRESPOND TO ACTUAL ORDER OF CONNECTIONS ON THE UNIT CASING ARROWS INDICATE DIRECTION OF WATER FLOW P TRAP IN MAIN DRAIN LINE IS REQUIRED PREVENT THE WATER MAKEUP LINE FROM FREEZING IT IS RECOMMENDED THE SOLENOID VALVE BE LOCATED BELOW THE ROOF LINE OF THE FACILITY OR BE INSULATED AND HEAT TAPED E SUGGESTED MANUAL SHUTOFF VALVES FOR ISOLATING AND BY PASSING EACH SOLENOID VALVE FOR MAINTENANCE PURPOSES ARE NOT SHOWN IN THIS PIPING SCHEMATIC F LARGER UNITS MAY HAVE TWO 2 SOLENOID VALVES FOR DRAINING THE UNIT S TWO 2 INDIRECT COOLING COILS cou MAINTENANCE IT IS RECOMMENDED THAT THE SUPPLY PIPING SYSTEM INCLUDE ONE HOSE BIBB OUTLET CONVENIENTLY LOCATED IN THE ROOF TO FACILITATE PERIODIC FLUSHING OF THE WATER TANKS DRAIN A GATE VALVE MAY BE ATTACHED DIRECTLY TO THE UNIT DRAIN PIPING OF WASTE WATER MUST MEET LOCAL CODES IN SOME CASES IT IS CONVENIENT TO CARRY THE DRAIN LINE DOWN INTO THE BUILDING WITH THE VALVE LOCATED AT AN ACCESSIBLE POINT TO FACILITATE FREQUENT TANK DRAINING SECTION IV PRE START UP Do not attempt start up without comp
30. IOMASC 2 Evaporative Units INSTALLATION OPERATION AND MAINTENANCE MANUAL AND DDC SYSTEM USER MANUAL FOR INDIRECT AND INDIRECT DIRECT EVAPORATIVE COOLING UNITS ATTENTION READ THIS MANUAL AND ALL LABELS ATTACHED TO THE UNIT CAREFULLY BEFORE ATTEMPTING TO INSTALL OPERATE OR SERVICE THESE UNITS CHECK UNIT DATA PLATE FOR TYPE OF GAS AND ELECTRICAL SPECIFICATIONS AND MAKE CERTAIN THAT THESE AGREE WITH THOSE AT POINT OF INSTALLATION RETAIN FOR FUTURE REFERENCE FOR YOUR SAFETY The use and storage of gasoline or other flammable vapors and liquids in open containers in the vicinity of this appliance is hazardous FOR YOUR SAFETY If you smell gas 1 Open Windows US 2 Don t touch electrical switches Here 3 Extinguish any open flame Intertek 4 Immediately call your gas supplier WARNING Improper installation adjustment alteration service or maintenance can cause property damage injury or death Read the installation operating and maintenance instructions thoroughly before installing or servicing this equipment WARNING Install operate and maintain unit inaccordance with manufacturer s instructions to avoid exposure to fuel substances or substances from incomplete combustion which can cause death or serious illness The state of California has determined that these substances may cause cancer birth defects or other reproductive harm INSTALLER S RESPONSIBILITY Installer
31. If the fan is not running 1 The BACview is indicating that another existing alarm condition is preventing the fan from running 2 Controller s supply fan start stop output BO 1 LED is lit 3 Unit enable relay RE 57 is energized or its normally open contact is closed 4 VFD tripped out on an overload fault the LCD on the VFD will display an F PF message dti Determine cause and rectify There is a short in the wiring Determine cause and rectify Replace main airflow switch Determine cause and rectify Determine cause and rectify Replace controller There is an open in the wiring Determine cause and rectify Determine cause rectify and reset DIAGNOSTICS NON CRITICAL ALARMS continued C Clogged Filter The filter air pressure switch has closed between the appropriate terminals on the unit s terminal strip located in the unit s main control panel indicating a clogged filter This alarm resets automatically once this conflict is resolved Filters are dirty Airflow switch sensing tubes are obstructed Airflow switch setpoint improperly set Short in the wiring between the control terminal strip and the airflow switch k Clean or replace filters Clear obstruction Adjust airflow switch setpoint such that the airflow switch s normally open contact closes once the supply fan VFD reaches its minimum speed Find the clogged filter swi
32. MUM OF 1 2 PLUS THE TOTAL SYSTEM STATIC PRESSURE W C K TO EXCEED THE NEGATIVE STATIC PRESSURE IN W C OF THE SECTION OF THE UNIT WHERE THE DRAIN IS INSTALLED AND DOUBLE WHEN SPACE PERMITS 10 30 09 C000659B FLOAT INDIRECT SECTION RESERVOIR DIRECT SECTION RESERVOIR OVERFLOW FLOAT DRAIN INDIRECT COIL OVERFLOW DRAIN PIPING HEADER DRAIN COOLING STAGE 1 MANUAL SHUTOFF VALVE BY OTHERS MANUAL SHUTOFF VALVE BY OTHERS VW 82 N O DRAIN VALVE COOLING STAGE 1 MANUAL SHUTOFF VALVE BY OTHERS VW 85 N O DRAIN VALVE COOLING STAGE 2 MANUAL SHUTOFF VALVE BY OTHERS VW 83 N O DRAIN VALVE COOLING STAGE 1 INDIRECT COIL PIPING HEADER DRAIN MANUAL SHUTOFF VALVE BY OTHERS VW 84 N O DRAIN VALVE COOLING STAGE 1 DRAIN FOR RESERVOIRS amp COIL 2 FLUSHING HOSE BIBB OUTLET FOR PERIODIC WATER TANK DRAIN FOR SUPPLY LINE 2 SUMP WATER MAKEUP LINE VW 81 3 WAY WATER SUPPLY X VALVE COOLING STAGE C000751 000751 EQUIPMENT LEGEND e VW 80 3 4 3 WAY VALVE FOR INDIRECT SUMP WATER MAKEUP W 81 3 4 3 WAY VALVE FOR DIRECT SUMP WATER MAKEUP W 82 1 OR 1 1 2 N O SOLENOID VALVE FOR INDIRECT SUMP DRAIN L
33. NT PARTS Replacement parts may be ordered from the factory Parts Department at 214 638 6010 The Parts Department can also be reached by email at parts 9 mestex com When parts are ordered MODEL NUMBER SERIAL NUMBER FACTORY ORDER F O and PART NUMBERS are required Dealer Contractor Name City Contact the Technical Services Department at 214 638 6010 for all warranty issues All warranty parts will be shipped freight allowed from the factory by normal ground service Warranty parts must be returned prepaid within 30 days Credit will be issued if part is complete defective and returned on time Filters and fuses are not covered under warranty Address State Zip Ph 20 SECTION X AZTEC DDC SYSTEM USER MANUAL Table of Contents Overview iaaaiaaaaaansaaaniaaasaaansanannnnnnnnnnnnnnnnnnnnannnsnnananaan 22 Networking 23 DDC System Default Settings 23 Unit Operating 25 MRT Expert Controls 25 Unit Off Mode 25 Unit Manual Mode eee 25 Unit Auto Mode ien 25 Scheduling Time 25 Cooling Night 27 Auxiliary Unit 27 MDT Expert Controls esses 27 Unit Off 27 Unit M
34. a surface Water being carried over from the direct evaporative section Evaporative media and or media water distribution pad damaged or partially blocked 2 Media water distribution header or orifices plugged Localized media face velocity exceeding 500 FPM 2 Evaporative media is damaged 3 Too much recirculating water 4 Average media face velocity exceeds 500 FPM 5 Uneven water distribution over evaporative media 1 Remove media and distribution pad Clean and or replace 2 Remove media water distribution pad and clean header and orifices 1a Inlet air filters are partially obstructed Clean or replace filters as required 1b Inlet face of media is partially ob structed Clean or replace evapora tive media as required 2 Check both faces of evaporative me dia for damage Replace as required 3 Adjust water flow rate to evaporative media until carryover stops by slow ing closing the water flow balancing valve in the recirculating pump s riser 4 Decrease air flow through air handler 5 Clean evaporative media and or water distribution header and or orifices J Cooling not functioning properly UC 01 and or relays not wired correctly or defective 2 Setpoint is lower than design conditions 3 Check outside wet bulb temperature 4 Non uniform air flow across the face of the evaporative media in the direct evaporative sectio
35. air temperature to rise above the Freezestat setpoint Reset the alarm via the UNIT RESETS menu tree in the BACview Unplug the input jack from the controller Did the display change to 40 F or less a No There is a short in the controller input Replace the controller Yes Disconnect the sensor wiring at the sensor Connect an ohmmeter to the sensor If it is shorted replace the sensor At 77 F the resistance should be 10 See thermistor output curve for other temperatures If it is not shorted there is a short in the wiring between the sensor and the input plug Determine cause and rectify Refer to Appendix II for a typical 10KQ thermistor output curve Jumper the input for the sensor Did the display change to 150 F or more a No There is an open in the controller input Replace the controller Yes Disconnect the sensor wiring at the sensor Connect an ohmmeter to the sensor If it is open replace the sensor At 77 F the resistance should be 10KQ See thermistor output curve for other temperatures If it is not open there is a break in the wiring between the sensor and the input plug Determine cause and rectify 37 DIAGNOSTICS CRITICAL ALARMS continued B Zone Sensor Failure The zone sensor has failed to communicate usable data to the controller for more than 6 seconds C Supply Air Sensor Failure The supply air sensor is providing the controller with invali
36. al Electrical Code Check the supply voltage before energizing the unit The maximum voltage variation should not exceed x 10 Phase voltage unbalance must not exceed 2 NOTE Should any original wire supplied with the unit have to be replaced it must be replaced with wiring material having a temperature rating of at least 105 C F Field Piping Water Piping All water piping must be in accordance with project specifications and the requirements outlined in any applicable local state and national codes Refer to drawing C000751 for typical piping Insert a manual shut off valve in the water supply line required for the unit s indirect evaporative section and if provided the direct evaporative section for each unit Complete the piping to each section s 3 4 make up water inlet Proper water quality and environmental conditions will give you long service life from your cooling tower and direct evaporative cooling unit Significant deviation from normal conditions may have a bearing on longevity of the equipment Normal circulating water chemistry falls within the follow ing limits pH between 6 5 and 8 0 e Chlorides expressed as NaCl below 750 ppm e Calcium expressed as CaCO below 1200 ppm except in arid climates where the critical level for scale formation may be much lower e Sulfates below 5 000 ppm if calcium exceeds 1200 ppm sulfates should be limited to 800 ppm less in arid clim
37. and critical components Rotate the fan s monthly Prior to beginning installation of a unit that has been in storage for weeks or months the unit and its components should be closely inspected Shipments are made F O B Dallas Texas by flat bed truck The unit is securely strapped tied and blocked to prevent shipping damage All shipments are checked by an inspector before they are accepted by the carrier Parts that are shipped unmounted are noted on the bill of lading These parts where feasible are packaged and shipped with the units Upon receipt of shipment all units should be checked against the bill of lading to insure all items have been received All equipment and any optional accessories should be checked carefully for physical damage in the presence of the carrier s representative If parts are missing or damage has occurred a claim should be filed immedi ately with the carrier All Indirect or Indirect Direct Evaporative Cooling Sys tems are given a complete operations test and control circuit checkout before shipment Copies of the wiring diagram piping diagram and bill of material are in cluded with each unit shipped If correspondence with the factory is necessary please provide the unit model and serial number C Optional Factory Service Periodic service on any piece of mechanical equip ment is necessary for efficient operation A nationwide service support network is available to provide quick and depe
38. ange to 150 F or more No There is an open in the controller input Replace the controller b Yes Disconnect the discharge air temperature sensor wiring at the sensor Connect an ohmmeter to the sensor If it is open replace the sensor At 77 F the resistance should be 10KQ See thermistor output curve for other temperatures If it is not open there is a break in the wiring between the sensor and the input plug Determine cause and rectify 38 DIAGNOSTICS CRITICAL ALARMS continued D Cooling Stage 1 1 Low water level in indirect sump Water Level Failure 2 Fill valve closed and or drain valve open Rectify water level See recommended float level adjustment in the Aztec Installation Operation and Maintenance section of this manual The depth of the water in the sump s should be half an inch below the top of the sump s overflow stand pipe Check valve positions and wiring a The fill valve should be open when BO 5 is energized as indicated by the illuminated LED If the fill valve is closed check the wiring If the wiring is correct then the valve is bad Replace the fill valve b The drain valve should be closed when BO 5 is energized as indicated by the illuminated LED If the drain valve is open it is malfunctioning and the wiring should be verified If the wiring is correct then the valve is bad Replace the drain valve E Cooling Stage 2 1 Low water level in d
39. anual 27 Unit Auto 27 Scheduling Time 27 Auxiliary Unit 28 Ventilating and Cooling Operating Modes 29 Ventilation 29 Cooling Mode uses 29 Energy Savings 29 General Cooling 29 Variable Frequency Drive Operation 30 Main Supply Fan VFD 30 Cooling Tower Fan VFD Control 30 Manual Override 30 Mixed Air Damper Control Modes 31 Mixed Air Temperature Control 31 Building Pressure 31 Percentage of Outside Air Control 31 Automatic Economizer 31 100 Outside Air ne ee 32 Automatic Fill and Drain 32 General Fill and Drain Operation 32 User Specified 32 Runtime 24 4 0000 32 Outside Air Temperature to Drain Sump s 32 M
40. anual 2 0 0 32 Electrical Demand and Usage Monitoring 33 Comfort Index and Satisfaction Rating 33 Comfort INdex aanaaaaaxaansaaansaannanannannnnnnnsnnnnnnnnanaa 33 Satisfaction 33 BIETA m 34 Clogged Filter ccr genis 34 Unit 35 Cooling Stage 1 Starts Reset 35 Cooling Stage 2 Starts Reset 35 Cooling Stage 1 Runtime Reset 35 Cooling Stage 2 Runtime Reset 35 Electrical Usage Demand Reset 35 Satisfaction Rating Timers Reset 35 Alarms eene ez 35 Multiplexed 2 44 4 36 Clock Set a 36 Duct Furnace IFD 36 Diagnostics Critical Alarms esses 37 Freeze 2 0 0422 37 Zone Sensor Failure 38 Supply Air Sensor 38 Cooling Stage 1 Water Level Failure 39 Cooling Stage 2 Water Level Failure 39 Diagnostics Non Critical Alarms 40 Unit Off Eah On isotope terit herir 40 Unit On Fan Off crt en 40 Clogg
41. ates to prevent scale formation Sulfides below 1 ppm Silica expressed as SiO below 150 ppm Iron below 3 ppm Manganese below 0 1 ppm No organic solvents No organic nutrients which could promote growth of algae or slime e Chlorine from water treatment below 1 ppm free residual for intermittent treatment below 0 4 ppm free residual for continuous chloration Insert a manual shut off valve in the drain line from each unit s indirect evaporative section and if provided the direct evaporative section s drain and indirect coil Interconnect the lines from each unit s indirect evapo rative section and if provided the direct evaporative section s drain and indirect coil NOTE The indirect evaporative section and if provided the direct evaporative section of every air handling unit are provided with an adjustable bleed valve that is plumbed to each section s overflow stand pipe System drainage for the constant water bleed from each evaporative section must be provided Units are provided with a freeze protection and automatic drain down kit install the solenoid valves in the following manner 1 Install the normally closed and if provided the 1 2 or 3 8 normally open water fill line drain solenoid valve in the water supply line at a point not subject to freezing temperatures and complete the piping to the make up water inlet connection provided on each unit 2 Install a manual shut off valve and the fact
42. ault unit operational mode To place the unit in Off Mode scroll through the UNIT MODES menu tree locate the AUTO OFF MANUAL branch and select OFF This will place the unit in the OFF mode The OFF mode prevents the fans and cooling from starting This mode will override the Time Clock and Night Setback functions Unit Manual Mode Manual Mode allows the supply fan and cooling tower fan to operate regardless of the Time Clock or Night Setback functions Cooling functions use the Occupied Setpoints To place the unit in Manual Mode scroll through the UNIT MODES menu tree locate the AUTO OFF MANUAL branch and select MANUAL This will place the unit in the MANUAL mode Unit Auto Mode Auto Mode has three different functions that control the supply fan cooling tower fan and general unit operation the time clock cooling night setback and a signal from an external source to an auxiliary digital input To place the unit in Auto Mode scroll through the UNIT MODES menu tree locate the AUTO OFF MAN branch and select AUTO This will place the unit in the AUTO mode This activates the three Auto mode functions Scheduling Time Clock The primary Auto Mode function is the Time Clock Schedule The Time Clock function allows the user to schedule the operational times of the unit There are four different schedules available 24 hour continuous operation daily holiday and override The daily schedule can be programmed for up to 4 separate
43. ch 2 Mount and wire remote control panel thermostats temperature sensors and any other field installed con trols as indicated on the unit control wiring diagram 3 Connectthe wires to the appropriate field wiring terminals as indicated on the unit control wiring diagram 4 Field wiring shall have a temperature rating of at least 105 C The minimum size of the supply cable circuit shall be sufficient for the maximum ampacity of the unit l Locating Temperature Controls The room or outdoor sensors should be mounted where they will not be subjected to direct impact of the heated air or radiant heat from the sun The side of building columns away from the heater or interior walls are usually the location best suited for mounting thermostats Controls with outdoor sensors require that the outdoor sensor be shielded from direct radiation from the sun Unit mounted sensors are factory located and mounted C000659B SUGGESTED P TRAP DESIGN FOR CONDENSATE DRAIN PANS UNDER A NEGATIVE PRESSURE 90 LONG RADIU TO DRAIN Pvc ELBOW 90 LONG RADIUS Pvc ELBOW NEPRE S PVC PIPE NIPPLE _ PVC RETURN BEND loeum PLUG DRAIN PAN N PVC ADAPTER FITTING PVC PIPE NIPPLE FPT x SLIP NOTE H TO BE A MINI
44. d temperature data 1 Room sensor disconnected 2 Short in room sensor wiring 1 Sensor circuit or sensor itself shorted 2 Sensor circuit or sensor itself open on the UNIT STATUS branch of the on the UNIT STATUS branch of the Jumper the input for the sensor Did Is the zone temperature as displayed BACview menu tree less than 0 F a Yes The room sensor is disconnected Reconnect the room sensor by verifying that no wires have come loose and that the terminal block connectors that bring the wires from the room sensor to the controller are also securely in place b No Continue Is the zone temperature as displayed BACview menu tree greater than 200 F a Yes There is a short in the room sensor wiring Determine cause of short and rectify b No There is a problem with the room sensor electronics Contact factory Unplug the input jack from the controller Did the display change to 40 F or less a No There is a short in the controller input Replace the controller b Yes Disconnect the sensor wiring at the sensor Connect an ohmmeter to the sensor If it is shorted replace the sensor At 77 F the resistance should be 10KQ See thermistor output curve for other temperatures If it is not shorted there is a short in the wiring between the sensor and the input plug Determine cause and rectify Refer to Appendix II for a typical 10KQ thermistor output curve the display ch
45. damper control functions AUTOMATIC FILL AND DRAIN CONTROL General Fill and Drain Operation The automatic fill and drain binary outputs for cooling stages 1 and 2 BO 5 and BO 6 respectively are controlled independently of each other The fill and drain valves are controlled via either a user specified schedule or a runtime odometer Switching between these control modes is accomplished through the provided BACview device The Cooling Stage 1 and 2 Water Level Failure Alarms are disabled when cooling stages 1 and 2 are drained as commanded by the user specified schedule or runtime odometer The binary outputs are energized by default to hold the fill valve open and the drain valve s closed during normal unit operation Once the DDC controller calls for a drain cycle based on the user configurable schedule the binary outputs will be de energized for a minimum of 15 minutes user configurable via the BACview to allow the unit ample time to drain its sump s Once the drain cycle is complete the outputs will energize and the fill cycle will begin filling the sump s with water With the drain cycle complete and the supply air temperature rising the outputs will energize and the fill cycle will begin when the zone or supply air temperature is within 5 F of the zone or supply air temperature setpoint This temperature deadband is user configurable via the BACview The outputs remain energized until the next time the drain cycle be
46. dia and Coils To attempt to clean evaporative media add one 1 cup of tri sodium phosphate TSP to the sump and operate recirculating pump for at least 30 minutes or until deposits have disappeared Drain sump Fill the sump with fresh water and operate the recirculating pump for 30 minutes to rinse the media Drain sump Fill the sump with fresh water before placing unit back into operation Coil surfaces must be kept clean of dirt and lint in order to operate at rated efficiency Coils should be inspected on a regular basis and cleaned as required CAUTION Solutions used to clean coils must not be corrosive to metals or materials used in the manufacture of this equipment If cleaning solutions are applied through means of high pressure spray care must be taken to avoid damaging the coil fins Always follow the manufacturer s warnings and directions for the coil cleaner you are using E Gaskets Gaskets are used on doors inspection covers some filter racks and some outdoor air dampers Inspect gaskets periodically and repair or replace as required F Caulking Inspect unit and add caulking as required G Casing Periodic cleaning of the casing is recommended to remove dirt grease and any corrosive substances that may harm the finish Rusted or corroded spots should be cleaned and repainted H Support Means Inspect the entire unit support means to be sure every thing is firmly in place ed SECTION IX REPLACEME
47. e building pressure setpoint As the building pressure falls below setpoint the controller signals the VFD to increase the speed of the main supply fan motor thereby increasing the building pressure until the building pressure equals the building pressure setpoint The main supply fan VFD will modulate the supply fan motor toward its minimum speed as the building pressure approaches the Building Pressure setpoint The main supply fan VFD will modulate the supply fan motor toward its maximum speed as the building pressure falls to the Building Pressure setpoint Cooling Tower Fan VFD Control The cooling tower fan speed varies based on the supply air temperature The controller modulates the output to the cooling tower fan VFD using a PID loop that compares the supply air temperature to the supply air temperature setpoint The controller will modulate the speed of the cooling tower fan motor to maintain the supply air temperature between the minimum and maximum supply air temperature setpoints As the supply air temperature rises to the supply air temperature setpoint the cooling tower fan motor and stage 1 circulating pump are enabled As the supply air temperature rises above the supply air temperature setpoint plus the Cooling Stage 2 Interstage Differential setpoint the stage 2 circulating pump is enabled As the supply air temperature rises above setpoint the controller signals the VFD to increase the speed of the cooling to
48. e Comfort Index and Satisfaction Rating values via the BACview to ensure the unit is operating effectively Low percentages for either of these points could indicate an suboptimal setpoint configuration Verify that all setpoints on the SETPOINTS branch of the BACview menu tree are reasonable and that no values were entered into the system incorrectly as this may negatively impact unit performance E 33 FREEZESTAT The Freezestat function automatically cycles the unit off branch of the BACview menu tree select Freezestat if the supply air temperature drops below the Freezestat SP and enter a new temperature The allowable setpoint for 3 continuous minutes On all units there is temperature range is 35 F 80 F an initial 8 minute delay prior activation The Freezestat function prevents the unit from starting The default for The Cooling Stage 1 and 2 Water Level Failure alarms this setpoint is 45 F To change the Freezestat setpoint are disabled while the Freezestat alarm is active scroll through the menu tree locate the SETPOINTS CLOGGED FILTER An optional clogged filter switch is required for this between terminals 227 and 228 on the unit s terminal function The Clogged Filter function automatically strip located in the unit s main control panel See the notifies the user of a dirty filter condition A Clogged Typical Wiring Schematic section of this manual for Filter indication will appear on the BACview This more informatio
49. e rises above the Cooling Setback temperature setpoint and the unit is scheduled to be off If the unit is scheduled to be off and the Cooling Setback function turns the unit on the unit will be cycled off once the room air temperature has fallen 2 F below the Cooling Setback setpoint This function toggles binary outputs BO 1 main supply fan start stop BO 2 stage 1 cooling pump start stop and BO 4 cooling tower fan start stop The default for the Cooling Setback setpoint is 100 F To change the Cooling Setback setpoint scroll through the SETPOINTS menu tree locate the Cooling Setback setpoint and enter a new temperature The allowable temperature range is 40 F 130 F Auxiliary Unit Enable The Auxiliary Unit Enable function overrides all other Auto Mode functions and cycles the unit into operation This function is activated whenever a contact is closed between terminals 229 and 230 on the unit s terminal strip located in the unit s main control panel Cooling functions use the Night Setback Setpoints See the Typical Wiring Schematic section of this manual for more information This function can be used with a twist timer toggle switch door switch exhaust fan interlock or any other dry contact to override the time clock schedule MDT Expert Controls The Aztec MDT Expert modulating discharge temperature control provides full information regarding unit operation and allows the user to adjust all operational para
50. e the desired cooling economizer temperature scroll through the SETPOINTS menu tree locate the Cooling Economizer setpoint and enter a new temperature The default for this setpoint is 55 F The allowable temperature range is 40 F 130 F General Cooling Control For MRT Expert control systems the cooling will cycle on and off as required to maintain a constant temperature The cooling outputs BO 2 amp BO 3 can be protected by an anti cycle timer which has a 3 minute off 3 minute on delay The anti cycle timer is enabled by default To disable the anti cycle timer scroll through the UNIT SETUP menu tree using the BACview locate the Use Clg Anti Cycle Timer field and set its value to No To change the desired cooling room temperature of an MRT Expert control system scroll through the SETPOINTS menu tree using the BACview locate the Occ Zone Stpt and enter a new temperature The allowable temperature range is 40 F 130 F For MDT Expert control systems the cooling will cycle on and off as required to maintain a constant discharge temperature For MRT Expert control systems the controller cycles the cooling on and off to maintain the supply air temperature within a defined operating window This window defines the maximum and minimum discharge temperatures To change the desired cooling discharge temperature of a MDT Expert control system scroll through the SETPOINTS menu tree using the BACview locate the Supply
51. ection on motor VFD 10 Push reset button and check amps and or starter tripped 11 Motor bearings seized 11 Check and or replace 12 Motor may be burned or incorrectly 12 Turn off power and check motor wired and wiring 13 Motor overheating 13 Check motor amp draw B Inlet air damper or Return 1 Damper motor and or end switch 1 Check wiring and or replace end air Outside air dampers not wired correctly or defective Switch operation not functioning 2 Dampers binding and or loose 2 Check and or replace properly see sequence 3 Building Pressure Transducer 3 Check and or replace components of operation for damper PT 13 See section on troubleshooting control PT 13 4 Building Pressure Transducer 4 Check wiring PT 13 5 Building Pressure Transducer 5 Install correctly See section on PT 13 troubleshooting PT 13 and manu facturer s cut sheet 6 Unit Control Module UC 01 6 Check and or replace Contact Fac defective tory 7 Unit Control Module UC 01 not 7 Check wiring wired correctly 8 Two position switch defective 8 Check and or replace 9 Damper motor defective 9 Check and or replace EI SECTION VII TROUBLESHOOTING GUIDE continued Fan and Cooling Mode continued Symptom Cause Remedy C There is no voltage at Cooling mode is disabled Enable the cooling mode obstructed dirty or damaged cooling relays RE 34
52. ed 41 Cooling Stage 1 Maintenance 41 Cooling Stage 2 Maintenance 41 amp 01332 a a 41 Menu Selection Tree for BACview 42 ModSt t 42 Unit Setup HOTKEY 9 42 Unit Modes HOTKEY 2 43 Unit Setpoints HOTKEY 43 Status Menu HOTKEY 4 44 Unit Resets HOTKEY 6 44 Alarms HOTKEY 1 44 Alarm Configuration 2 44 Schedules HOTKEY 7 44 Clockset HOTKEY 0 45 Electrical Usage and Demand HOTKEY 5 45 Comfort Index HOTKEY 8 45 Ovetrid s iR ERE 45 1 46 10 000 Ohm Thermistor Output Curve 46 Appendix ll 47 Flex 6126 Controller Specifications 47 Appendix 1 een 48 Typical Wiring Schematic 48 Appendix 49 Typical Wiring Schematic 49 EL OVERVIEW A glossary has been provided to assist the reader in understa
53. ed modulation functions and may result in poor unit performance as the variable frequency drive s will not be able to modulate the motor s to optimize performance as environmental conditions change 30 MIXED AIR DAMPER CONTROL MODES There are three different modes that control the unit damper operation Mixed Air Temperature Building Pressure and Percentage of Outside Air control These operating modes are selected through the menu tree of the BACview or PC Not all damper modes are available on all units The mixed air dampers also have an economizer function to reduce energy consumption based on outside air conditions thereby improving unit efficiency The economizer function is described at the end of the Mixed Air Damper Control Modes section of this manual Outside air dampers will remain closed during the unoccupied period if the supply fan is off or if the room temperature is less than 45 F and the supply fan is running Mixed Air Temperature Control Mixed Air Temperature control varies the percentages of outside air and return air to maintain a constant mixed air temperature To place the damper operation in Mixed Air Temperature mode scroll through the menu tree locate the UNIT MODES branch and select MA Temp Ctrl Next scroll through the menu tree locate the SETPOINTS branch select Mixed Air and enter the desired temperature The allowable range is 30 F 90 F Building Pressure Control Building P
54. edia and coil s Clean if necessary f Inspect all orifices in water distribution system Clean if necessary 9 Flush sediment and debris from Cooling Tower and Direct Evaporative Cooling Section sump s 4 Off Season or Yearly a Complete the monthly and quarterly maintenance schedule b Inspect all fan wheels and props Clean if necessary c Check that all fan wheels and props are securely set on the motor shaft d Inspect all electrical components connections and terminals Clean and tighten where necessary e Lubricate fan motor s as directed by motor manufact urer f Inspect fan motor s wiring for loose connections Lightly oil all door latches Check that cabinet is weathertight replace door gas kets and recaulk as necessary zo WARNING DO NOT OPERATE THE SUPPLY FAN OR COOLING TOWER FAN IN THE AIR HANDLER S INDIRECT EVAPORATIVE SECTION DURING ANY CLEANING OF THE UNIT S EVAPORATIVE MEDIA CAUTION The evaporative media has a definite polarity and must be installed correctly to give trouble free results Proper installation is that the 45 flutes slope toward the air entering side The 15 flutes slope down toward the leaving air side See drawing below AIR FLOW NOTE Keep screened air intakes clear of obstruc tions at all times B Lubrication Instructions Item Manufacturer Bearing Type All 3 phase US Baldor Single row ball fan motors or equal bearings 1 HP to 100 HP
55. efore the BACnet instance number is 24016 The DDC controller will not function if the rotary address setting is incorrect DDC SYSTEM DEFAULT SETTINGS The following is a list of Aztec DDC controller defaults These are the default operating parameters set at the factory prior to shipment Unit Configuration ITEM DEFAULT RANGE Unit Network Address 16 00 99 rotary switches Unit Enable OFF AUTO OFF MANUAL 3rd Party Zone Temperature Control Enable No No Yes T 1 Supply Air Temperature Control Supply Fan VFD Operation As specified 2 Building Pressure Control 1 Building Pressure Control Mixed Air Damper Operation As specified 2 Mixed Air Temperature Control 3 96 Outside Air Control MRT modulating room temperature control Control System As specified MDT modulating discharge temperature control Stage 2 Cooling Installed As specified No Yes gt 99 DDC SYSTEM DEFAULT SETTINGS continued Cooling Configuration ITEM DEFAULT RANGE Fill Drain Schedule Enable No No Yes 1 Monday 2 Tuesday Cooling Stage 1 Indirect Fill Drain Schedule 1 3 Wednesday 4 Thursday 5 Friday 6 Saturday 7 Sunday 1 Monday 2 Tuesday Cooling Stage 2 Direct Fill Drain Schedule 1 3 Wednesday 4 Thursday 5 Friday 6 Saturday
56. electrician or other individual who has been properly trained in handling live electrical components to perform these tasks Failure to follow all electrical safety precautions when exposed to live electrical components could result in death or serious injury Make sure all doors and service panels have been closed or replaced Check the indirect evaporative section s and if pro vided the direct evaporative section s sump low water level recirculating pump shutoff switch The low level switch contact will be normally closed when the sump is filled with water As this switch is not field repairable replace if found defective Turn main disconnect switch off Check the incoming line voltage to match unit rating plate rating If voltage is over 10 of nameplate rating or phase voltage unbalance is over 2 notify contractor or power company Fans Are Enabled And Disabled By The Following MRT Expert or MDT Expert With A BACview KP 01 To enable the fans go to Unit Modes and enter MANUAL this mode will enable the fans To also enable the fans go to Unit Modes and enter AUTO this mode has four different functions that control the fans and unit operation They are a Time Clock Heating and Cooling Night Setbacks and signal from an external source to an auxiliary digital input To disable the fans go to Unit Modes and enter OFF NOTE A BACview or PC is required to change Unit Modes If powe
57. eter was left in the ON state continuously the alarms can still trigger on alarm conditions however to reset the alarms from this state you must move change the Alarm Reset parameter to OFF then ON then OFF again Otherwise the alarms will not reset and you will not be alerted if an alarm that was previously triggered happens to trigger again during the period the alarm remained active A history of alarms can be viewed on the Alarms screen of the BACview To view the alarms history locate the Alarms page in the BACview menu tree The alarms history shows active alarms alarms that have returned to normal and manually cleared alarms 35 MULTIPLEXED INPUTS DDC controllers are designed with a finite number of inputs and outputs Multiplexing expands the functionality of the controller by allowing multiple devices to effectively share the same input This is usually accomplished by connecting resistors either in a series or parallel configuration to an analog input A Switch is used in conjunction with each resistor When a switch is closed the resistance at the controller input changes This allows the controller to identify which Switch has closed The controller is programmed to associate each different resistance with a specific function The Aztec DDC system uses a multiplexed input only on units equipped two stages of cooling The user is notified of the low water level condition through the BACview The indirect a
58. etting the time date and Daylight Savings function The following instructions demonstrate how to set up a sample schedule using the BACview remote An example of a typical schedule would be to have the unit On Monday through Friday from 6 00 AM to 5 00 PM except during the week of Thanksgiving when the unit will be Off The unit will run each weekday during the Thanksgiving shutdown from 8 00 AM until noon while a maintenance crew is in the building The maintenance crew will come in at 5 00 AM on Monday to complete preliminary tasks in preparation for the week We will use this sample schedule as our guide in programming the sample schedule Refer to the Menu Selection Tree for BACview section of this manual for more information about the BACview buttons hotkeys and menus The sample schedule and instructions below are just a guide you may skip the rest of the Scheduling Time Clock section of this manual if you are already comfortable programming daily holiday and override schedules Simply determine what schedule you want the unit to operate on and set the schedule in the BACview accordingly 1 Use the FN 7 hotkey to jump directly to the Schedules screen of the menu tree While holding the FN key press the 7 key and the Schedules screen will appear The BACview may prompt you for the User password The default password is 0000 Unit Schedules Z4hr Operation No Fri 28 8 2012 12 13pm gt Holiday
59. ge 1 Runtime Reset To reset the record of the length of time cooling stage 1 has been running scroll through the menu tree locate the UNIT RESETS branch and select Cooling Stage 1 Runtime Reset Press the Enter key The word OFF should flash Now press the INC key and the word ON should flash on the display Press the Enter key again and ON should stop flashing Repeat this process so the word OFF is displayed and not flashing The Cooling Stage 1 Runtime value has now been reset to zero and the Cooling Stage 1 Runtime function has been rearmed Cooling Stage 2 Runtime Reset To reset the record of the length of time cooling stage 2 has been running scroll through the menu tree locate the UNIT RESETS branch and select Cooling Stage 2 Runtime Reset Press the Enter key The word OFF should flash Now press the INC key and the word ON should flash on the display Press the Enter key again and ON should stop flashing Repeat this process so the word OFF is displayed and not flashing The Cooling Stage 2 Runtime value has now been reset to zero and the Cooling Stage 2 Runtime function has been rearmed Electrical Usage Demand Reset To reset the record of the electrical usage and demand scroll through the menu tree locate the UNIT RESETS branch and select Electrical Usage and Demand Reset Press the Enter key The word OFF should flash Now press the INC key and the word ON should flash on the display Press the Enter key again and ON sh
60. gins User Specified Schedule The DDC controller will drain the sump s when the current date and time match the user programmed date and time user configurable via the BACview as long as the unit is in the unoccupied mode For example the indirect section stage 1 could be programmed to drain every Monday morning at 1 00 AM and the direct section stage 2 every Monday morning at 3 00 AM so as not to interfere with cooling demands during the occupied period Runtime Odometer The DDC controller will drain the indirect section when the cumulative stage 1 runtime reaches the Cooling Stage 1 Runtime Trip setpoint and will drain the direct section when the cumulative stage 2 runtime reaches the Cooling Stage 2 Runtime Trip setpoint as long as the unit is in the unoccupied mode If the unit is in the occupied mode when the trip point is reached the sump s will drain the next time the unit switches to unoccupied mode The runtime trip setpoint for each stage of cooling can be set via the BACview The factory default value for the Cooling Stage 1 and 2 Runtime setpoints is 100 cumulative hours of runtime Once the drain cycle is complete the outputs will energize and the fill cycle will begin filling the unit with water The outputs remain energized until the next time the drain cycle begins Outside Air Temperature to Drain Sump s If the outside air temperature falls below the OA Temp to Drain Sump s setpoint the default is 36
61. hip from the factory with supply air temperature control as the default control mode for both the main supply fan VFD and the optional cooling tower fan VFD Main Supply Fan VFD Control The supply fan speed varies based on one of two modes supply air temperature control or building pressure control In supply air temperature control mode the supply fan speed varies based on the supply air temperature The controller modulates the output to the supply fan VFD using a PID loop that compares the supply air temperature to the supply air temperature setpoint The controller will modulate the speed of the main supply fan motor to maintain the supply air temperature between the minimum and maximum supply air temperature setpoints The main supply fan VFD will modulate the supply fan motor toward its minimum speed as the supply air temperature falls to the minimum supply air temperature setpoint The main supply fan VFD will modulate the supply fan motor toward its maximum speed as the supply air temperature rises to the maximum supply air temperature setpoint In building pressure control mode the controller modulates the output to the supply fan VFD using a PID loop to maintain the building pressure at the building pressure setpoint As the building pressure rises above setpoint the controller signals the VFD to decrease the speed of the main supply fan motor thereby decreasing the building pressure until the building pressure equals th
62. his 2 Use YES Stat OFF Z4hr 0 Stop Time 17 0 Month 11 1 12 Prev gt Next Day gt Home 19 1 31 L GOUT Repeat this step for the 20th 21st 22nd and 23rd Tuesday Wednesday Thursday and Friday using Holiday Schedules 3 through 10 then proceed to the next step 9 Since the maintenance crew will be in the building at 5 00 AM on Monday we will need an override schedule to override part of the Holiday schedule we just created Navigate back to the Schedules screen using the FN 7 hotkey Move the cursor to select the Override field and press Enter Set the start time to 5 00 AM and the stop time to 8 00 AM Remember the Override schedules override the Holiday schedules and represent the period during which the unit is to be ON Set the Month field to 11 November and the Day field to 19 Monday the first weekday of Thanksgiving week in 2012 Your screen should now look like this Holiday Sch 2 Use YES Start Pinel lt 5 2 0 Stat OFF 24hr Stop Time 8 0 19 1 31 gt Home LOGOUT Month 11 13 12 Prev gt Next 10 Press the link key corresponding to the Home field on the screen to return to the Home screen The sample schedule is programmed and the unit will automatically turn on and shut off based on the daily holiday and override schedules Cooling Night Setback The Cooling Night Setback function automatically cycles the unit on if the room temperatur
63. irect sump s Water Level Failure 2 Fill valve closed and or drain valve open Rectify water level See recommended float level adjustment in the Aztec Installation Operation and Maintenance section of this manual The depth of the water in the sump s should be half an inch below the top of the sump s overflow stand pipe Check valve positions and wiring a The fill valve should be open when BO 6 is energized as indicated by the illuminated LED If the fill valve is closed check the wiring If the wiring is correct then the valve is bad Replace the fill valve b The drain valve should be closed when BO 6 is energized as indicated by the illuminated LED If the drain valve is open it is malfunctioning and the wiring should be verified If the wiring is correct then the valve is bad Replace the drain valve zc DIAGNOSTICS NON CRITICAL ALARMS This section should assist the user in troubleshooting critical alarms that have been displayed on the BACview These faults require the operator to correct the condition and reset the alarm before normal unit operation resumes Alarm Cause Remedy A Unit Off Fan On The controller has not activated the unit enable output to start the fan but the fan status input is receiving a signal that the fan is running This alarm resets automatically once this conflict is resolved If the fan is running 1 Controller s supply fan start s
64. is displayed at the BACview and system PC in text format In the Diagnostics section of this manual you will find a list of all alarms and possible causes and solutions All of the features of the Aztec system are designed to provide the user with real time information At any time the user can display all of the operational parameters make changes if necessary and observe the various temperature pressure and damper readings The system s diagnostic capabilities provide the user with up to the minute status reporting BACview service module or WebCTRL internet connection is required for these features 090 The DDC system is adaptable to a variety of different network architectures and protocols Each controller has built in protocol translation and can be NETWORKING a special adapter card that must be ordered with the configured for operation on ARCnet156 or EIA 485 vendor communication networks See Appendix II for specific controller specifications The DDC system can be connected to most 3rd party building automation systems Some systems may require the use of special routers interfaces or other network communication devices LON systems require unit Ethernet systems require an interface that can be ordered with the unit or sourced from a networking The BACnet device instance number for the controller is 24000 the rotary address setting The default address for all Aztec DDC units is 16 ther
65. le by pressing one of the 4 keys located directly below the screen Special Functions FN MUTE Clear Alarms FN period Module Status MODSTAT FN 9 Configuration Access to the Unit Setup page requires the User or Admin Password Changes to the Unit Setup page after the unit leaves the factory can adversely affect unit operation in the field Changes to the PID Loop settings are only visible when logged in using the Admin Password Do not make changes to the parameters on this page without first contacting the factory The default User Password is 0000 The default Admin Password is 1111 e BACview Unit Modes Auto Off Manual Manual Home Setpnts 5Status ALARM Link keys Function key The following procedure describes how to change an operational parameter of the unit via the BACview In this example we will use the Unit Modes screen to change the unit mode from Off to Manual 1 The Home screen shows Aztec Contact Information on the first line of the backlit display From the Home screen press the MODES link key that corresponds to the Unit Modes screen The link keys are located just below the backlit display as shown in the previous figure 2 The Unit Modes screen will appear on the backlit display The unit ships from the factory with the Auto Off Manual parameter set to Off To change this parameter to Manual or Auto use the arrow keys to move the cursor so that Off is
66. letely reading and understanding this manual along with the Burner if applicable Pre Start Up The owners representative or equipment operator should be present during start up to receive instructions on care and adjustments of the equipment All equipment has been factory tested adjusted metered and inspected to meet conditions set at the time the order was placed Only minimal adjustments should be required All information in this service manual is typical All products are semi custom and changes may occur CAUTION Line side of disconnect may be energized Follow proper lockout tagout procedures NOTE All servicing and adjustments of the Indirect or Indirect Direct Evaporative Cooling unit should be performed by a qualified service engineer Perform a visual inspection internally and externally to make sure no damage has occurred that unit is level and that everything is secure This inspection is very important and should be completed with greatest care given to detail A good pre start inspection will insure against possible unit damage on start up and will save valuable analysis time 1 Check that the physical condition of the unit exterior is acceptable 2 Check that the insulation inside of unit is properly secured 3 Remove all shipping blocks brackets and bolts from supply fan base with optional isolation base 4 Check all terminals for loose connections and inspect all wiring terminations
67. meters using the BACview panel See the Menu Selection Tree for BACview section of this user manual for instructions that show how to change parameter values via the BACview Unit Off Mode Off Mode is the default unit operational mode To place the unit in Off Mode scroll through the UNIT MODES menu tree locate the AUTO OFF MANUAL branch and select OFF This will place the unit in the OFF mode The OFF mode prevents the fans and cooling from starting This mode will override the Time Clock function Unit Manual Mode Manual Mode allows the supply fan and cooling tower fan to operate regardless of the Time Clock function To place the unit in Manual Mode scroll through the UNIT MODES menu tree locate the AUTO OFF MANUAL branch and select MANUAL This will place the unit in the MANUAL mode Unit Auto Mode Auto Mode has two different functions that control the supply fan cooling tower fan and general unit operation the time clock and a signal from an external source to an auxiliary digital input To place the unit in Auto Mode scroll through the UNIT MODES menu tree locate the AUTO OFF MAN branch and select AUTO This will place the unit in the AUTO mode This activates the two Auto mode functions Scheduling Time Clock The primary Auto Mode function is the Time Clock Schedule The Time Clock function allows the user to schedule the operational times of the unit There are four different schedules available 24 hour continuou
68. much higher flow rate than the direct evaporative media It is common to have water carryover off of the media although the carryover is normally confined within the cooling tower section If adjustment is deemed necessary there are ball valves located in the inlet plenum to adjust water flow Make small adjustments and make sure all of the inlet filters are in place and access panel is closed while unit stabilizes with each new setting Check all dampers for proper operation and that the linkage does not bind and also see Sequence of Op eration for damper control modes Disable the fans Safety Controls Check Firestats These limit controls are not adjustable and are checked at the factory Reset the red button s to be sure they are ready for operation Contact factory if these switches fail to reset SECTION VI UNIT SHUTDOWN Extended Shutdown Disable the cooling for 30 seconds then disable the fan 2 Open the main electrical disconnect switch 3 Ifthe unit is to remain idle for an extended period the blower and motor shafts should be rotated by hand to spread the grease over the bearings 4 Drain sump s and shut off all water valves gt B Emergency Shutdown ONLY 1 Open the main electrical disconnect switch edid SECTION VII TROUBLESHOOTING GUIDE The following is a simplified list of possible problems and typical causes and remedies However it does not cover all possibilities
69. n 5 Incorrect water flow over direct section s evaporative cooling media 6 Building exhaust air relief fan s are not operating 7 Ventilation openings are closed or not properly sized 8 Media pads are not uniformly wet 9 Water flow rate from cooling tower pump has decreased 10 Water temperature from cooling tower has increased Check wiring and or replace bad components 2 Adjust setpoints on BACview or with PC 3 Abnormally high wet bulb tempera tures will decrease performance 4 Clean and or replace dirty or damaged air filters Check evaporative media for damage on entering and leaving air surfaces Replace if necessary 5 Open the water flow balancing valve provided in the direct evapo rative section s recirculating pump riser The recommended flow rate is 1 5 2 GPM per square foot of media pad top area If water flow is increased be sure to check again for water carry over 6 Check power source Close or con nect interlock to operate fan s 7 Open for proper relief air flow Check job specifications for proper sizing 8 Check and clean evaporative me dia water distribution pad water distribution header and orifices 9 Check pump and piping from tower to indirect cooling coil for blockage 10 Check media in cooling tower for damage and also check water recir culation rate 14 SECTION VII TROUBLESHOOTING GUIDE continued Fan and Cooli
70. n function is activated whenever a contact is closed 34 UNIT RESETS This section should assist the user in resetting alarms and cycle counters which have been displayed on the BACview WARNING Activating a reset purges and renders irretrievable all previously accumulated data for that particular status feature Cooling Stage 1 Starts Reset To reset the record of the number of times cooling stage 1 has cycled on scroll through the menu tree locate the UNIT RESETS branch and select Cooling Stage 1 Starts Reset Press the Enter key The word OFF should flash Now press the INC key and the word ON should flash on the display Press the Enter key again and ON should stop flashing Repeat this process so the word OFF is displayed and not flashing The Cooling Stage 1 Starts value has now been reset to zero and the Cooling Stage 1 Starts function has been rearmed Cooling Stage 2 Starts Reset To reset the record of the number of times cooling stage 2 has cycled on scroll through the menu tree locate the UNIT RESETS branch and select Cooling Stage 2 Starts Reset Press the Enter key The word OFF should flash Now press the INC key and the word ON should flash on the display Press the Enter key again and ON should stop flashing Repeat this process so the word OFF is displayed and not flashing The Cooling Stage 2 Starts value has now been reset to zero and the Cooling Stage 2 Starts function has been rearmed Cooling Sta
71. nd direct section pumps are each equipped with a float switch and the controller can enable disable cooling stages 1 and 2 individually based on sensed water levels in each section of the unit A stage of cooling can only be enabled if its corresponding low water level float switch is closed The resistance measured at the controller input UI 03 changes state based on which switches are closed as shown in the following table Resistance at UI 03 as a Function of Float Switch States Cooling Stage 1 Low Water Level Float Switch SW 10 Cooling Stage 2 Low Water Level Float Switch SW 11 Resistance at Controller Input UI 03 Closed Closed 0Q Open Closed 4 02 kQ Closed Open 8 06 kQ Open Open 12 08 CLOCK SET The Clock Set function is used to set the current time and date as well as enabling Daylight Saving Time To set the clock scroll through the menu tree locate the CLOCKSET branch select Date and enter a new date and time Select DST to enable Daylight Saving Time Daylight Saving Time is the default For your convenience Daylight Saving Time has been preprogrammed for the next several years To reset the starting and ending DST dates scroll through the DST menu tree locate the desired year and enter a new date If your area does not subscribe to Daylight Saving Time set the AMOUNT value to 000 DUCT FURNACE IFD CONTROL For Aztec units equipped with an IFD 160 320 or 480
72. ndable servicing of make up air heating ventilating or air handling types of equipment Factory start up service is also available which includes the presence of a service engineer to supervise the initial start up and adjustment of the equipment and provide instructions for the owner s maintenance personnel in proper operations and maintenance Consult factory for quotations on start up or periodic service SECTION Ill INSTALLATION All electrical connections must conform to the current edition of ANSI NFPA No 70 National Electrical Code and applicable local codes The following recommen dations are not intended to supplant any requirement of federal state or local codes having jurisdiction Authorities having jurisdiction should be consulted before installations are made Local codes may require additional safety controls and or interlocks All installations in airplane hangers must be in ac cordance with current ANSI NFPA No 409 instal lations in public garages must be in accordance with current NFPA No 88A and NFPA No 88B A Handling the Equipment As explained previously the basic unit is designed for shipping in one piece where shipping limitations allow Some optional accessories may require field mounting The Indirect or Indirect Direct Evaporative Cooling System has been designed for rigging and handling through the use of special lifting lugs installed on the top and or sides of each unit When unloading
73. nding distinctive terms and phrases These terms and phrases appear in italics The Aztec Digital Control System is designed to give the user the ultimate in unit performance and operational flexibility adaptability and reliability in a user friendly package The Aztec DDC system accepts single or multiple units on the system network Each unit ships with a BACview remote The operating parameters for individual units may be input through the BACview A PC may also be connected to the network This allows the user to configure each unit separately or all units can be configured simultaneously A controls contractor can provide assistance in networking Local access port connection for BACview M nn Figure 1 BACview ships with a cable One end of the cable consists of a pre wired black screw terminal connector while the other end consists of a 5 pin red tipped plug For MRT and MRT Expert systems plug the pre wired black screw terminal connector into the back of the BACview and plug the 5 pin red tipped plug into the bottom of the room sensor Because the room sensor is hard wired to the controller via the Rnet port on the left hand side of the controller and the BACview is connected to the room sensor via the plug connection on the bottom of the room sensor this creates a communications link between the BACview and the controller without having to directly wire the BACview to the controller It is ea
74. ndustrial equipment should not attempt the initial adjustment and checkout procedure which is essential before such installations may be considered ready for operation This manual should be made readily available to all operating personnel as an aid in troubleshooting and proper maintenance Due to the custom nature of this equipment not all possibilities are addressed in this manual The customer or installer can obtain specific unit information from the local sales representative or by contacting the factory directly WARNING Failure to comply with general safety information may result in extensive property dam age severe personal injury or death B Shipping Base Indirect or Indirect Direct Evaporative Cool ing units are shipped completely assembled where shipping limitations or job specifications allow Any optional accessories shipped separately are shipped as assembled sections Any wired accessories which have been disassembled for separate shipment require no additional conduit or wire for field reassembly All wire leads will be tagged for ease of reconnection in the field If the unit and or accessories cannot be installed immediately they should be stored in a clean dry environment If this is not possible and the unit must be stored outdoors it should be protected from the weather with tarpaulins or plastic coverings Do not assume that simply covering a unit will keep insects dust and condensation out of the unit
75. ne pressure The depth of the water in the sump should be 1 2 below the top of the sump s overflow stand pipe 12 REF FE B WATER LEVEL HUDSON FLOAT VALVE SUMP TANK OVERFLOW DRAIN ELBOW 1 SEIT i C000738 For remote cooling towers supplied either by Aztec or others plumb the supply and return lines from the cool ing tower to the coil inlet and outlet connections provid ed on the indirect cooling coil in each Aztec unit Building Pressure Transducer Piping PT 13 Pipe the high side to a location inside the building that will not be affected by air movement Pipe the low side to the atmosphere positioned so it will not be affected by the wind and not exposed to the elements Be sure that all tubing is clean and clear of any debris before installing tubes on the transducer G Duct Connection Install duct work with adequate flexible connections to isolate vibration from the duct work duct work should have taped or caulked seams Duct work should be properly sized so as not to inhibit airflow This information should be cross checked with the position of support beams and stand pipes to insure that clearance dimensions coincide with those of the unit H Field Wiring and Remote Control Installation 1 Connect the power lines to the line side of the main disconnect swit
76. ng Mode continued Symptom Cause Remedy K Excess water flow from the indirect or direct evaporative section s sump into the system drain 1 Check if adjustable water bleed off valve is open too far and bleed off rate is excessive 2 Verify that water level in indirect and direct evaporative section s sump is correct 3 Indirect or direct evaporative section s sump water fill and level control valve defective 1 Minimum bleed off rate is 3 626 of the total water flow being recirculated 2 Water level in the sump should be 1 2 below the top of the sump s overflow standpipe See drawing C000738 in Section III Installation for reference 3 Repair or replace valve 215 SECTION VII TROUBLESHOOTING GUIDE continued To Calibrate the Building Pressure Transducer PT 13 1 2 3 Remove the tubes at the Low and High pressure 4 With the use of a BACview 6 KP 01 place the unit in the Building Pressure mode See the DDC Control System User Manual fittings 5 The voltage at COM and OUT will vary between The voltage at COM and OUT should be 2 5 VDC 0 to 5 VDC 0 VDC means the building is in a If not adjust Z do not adjust S negative pressure and should open the Outside Air Make sure the Low and High fittings are clean and close the Return Air damper 5 VDC means the and clear do not insert any sharp objects into building is in a positive pressure and should o
77. ng tape is in place before unit is set Be careful not to allow gaps where two pieces of sealing tape meet A bubble level must be used in the leveling process Measure across diagonals to check for squareness Allowable tolerance is 1 4 difference between diagonal measurements Double check approval prints before setting the unit Upon completion of setting the curb apply roofing ma terial and flashing as required Refer to your unit roof curb drawing D Location of Accessories Where applicable standard or optional accessories will be placed inside the fan section of the unit for shipment and must be removed and installed by the mechanical or electrical contractor Remotely located discharge or inlet dampers must be equipped with an end switch and interlocked to insure maximum design opening before starting and running circuits may be energized Field constructed intake accessories should be properly designed to minimize the entry of rain and snow Adequate building relief must be provided so as to not over pressurize the building when the unit is operating at its rated capacity This can be accom plished by taking into account through standard engineering methods the structure s designed infiltra tion rate by providing properly sized relief openings by interlocking a powered exhaust system or by a combination of these methods E Electrical Connections WARNING Open all disconnect switches and secure in that position
78. ock not closed or connected Recirculating pump may be internally grounded or have heat damage 3 5 VFD ramped down 5 See sequence of operation F Recirculating pump 1 Water level in indirect or direct 1 Fill to proper level in direct or indirect evaporative section sump is low evaporative section 2 Low sump water level switch is 2 Check and or replace Close or connect customer interlock 4 Turn off power and check pump and wiring 5 Pump basket screen is blocked 5 Clean screen if necessary 6 BO 2 and or BO 3 not energized 6 See sequence of operation 7 Multiplex resistors are burnt 7 Check and or replace G White mineral deposits 1 Water bleed rate is too low 1 Increase water bleed rate by open collecting on face of ing the adjustable bleed valve media in indirect or direct provided Minimum bleed off rate is evaporative section 3 6 of the total water flow being recirculated 2 Low recirculating water flow rate 2 Open the water flow balancing valve provided in the direct evaporative section s recirculating pump riser The media is essentially self cleaning with a water flow rate of 1 5 2 GPM per square foot of media pad top area If water flow is increased be sure to check again for water carry over ES SECTION VII TROUBLESHOOTING GUIDE continued Fan and Cooling Mode continued Symptom Cause Remedy H Uneven water distribution over evaporative medi
79. ogout e Holiday o Holiday1 typical 1 through 12 Use Start Time Stop Time Month Day Previous Next Home Logout e Override o Override1 typical 1 through 2 Use Start Time Stop Time Month Day Previous Next Home Logout 44 Yes No Yes No hr min hr min SUN MON TUE WED THU FRI SAT Yes No hr min hr min 1 12 1 31 Yes No hr min hr min 1 12 1 31 MENU SELECTION TREE FOR BACVIEW continued Clockset HOTKEY 0 e Time hh mm ss Date dd mm yy e Previous e DST o Start Time hh mm o Amount 060 o Beg Mar 112012 End o Beg Mar 102013 End o Beg Mar 092014 End o Beg Mar 08 2015 End o Beg Mar 132016 End o Beg Mar 122017 End o Beg Mar 112018 End o Beg Mar 102019 End o Beg Mar 082020 End o Beg Mar 142021 End o Previous Nov 04 2012 Nov 03 2013 Nov 02 2014 Nov 01 2015 Nov 06 2016 Nov 05 2017 Nov 04 2018 Nov 03 2019 Nov 01 2020 Nov 07 2021 Electrical Usage and Demand HOTKEY 5 The Electrical Usage Menu displays up to the minute electrical usage data Prev Home Instantaneous Demand kWh Today kWh Yesterday kWh Month to Date kWh Last Month kWh Year to Date kWh Last Year Peak Demand Today Peak Demand Yesterday Peak Demand Month to Date Peak Demand Last Month Peak Demand Year to Date Peak Demand Last Year kW kWh kWh kWh kWh kWh Comfort Index HOTKEY 8 Comfort Index Satisfaction
80. oom or outside air temperature setpoint The relationship between these values is described in the Cooling Mode section of this manual Cooling Mode During the Occupied Cooling mode Cooling Stage 1 is activated whenever the room or outside air temperature is 2 F above the Occupied Zone setpoint and is deactivated at the Occupied Zone setpoint Cooling Stage 2 is activated whenever the room or outside air temperature is 2 F above the Occupied Zone setpoint plus the Cooling Stage 2 Interstage Differential setpoint the default value is 2 F and is user configurable via the BACview and is deactivated 2 F above the Occupied Zone setpoint During the Unoccupied Cooling mode MRT Expert systems only Cooling Stage 1 is activated whenever the room or outside air temperature is at the Cooling Night Setback setpoint and is deactivated 2 below the Cooling Night Setback setpoint Cooling Stage 2 is activated whenever the room or outside air temperature is at the Cooling Night Setback setpoint plus the Cooling Stage 2 Interstage Differential setpoint and is deactivated at the Cooling Night Setback setpoint Energy Savings Mode The Energy Savings Mode will automatically disable the cooling if the outside air temperature is below the Cooling Economizer setpoint This function is similar to an inlet duct thermostat The cooling will cycle back on if the outside air temperature rises 3 F above the Cooling Economizer setpoint To chang
81. ory provided normally open solenoid valve in the line from the unit s indirect cooling coil and the indirect and direct evapora tive section s sump drain connection Interconnect the line from the unit s indirect cooling coil and the indirect and direct evaporative section s sump drain connection to the indirect and direct evapora tive section s overflow connection to form a common drain line and plumb to an appropriate drain Install a P Trap in the common drain line from the unit s indirect evaporative section and if provided the direct evapora tive section drain and overflow connections Provide the P Trap height as shown in Drawing C000659B For colder climates be sure to provide means to completely drain the indirect cooling coil and the indirect and direct evaporative section sumps for freeze protection Solenoid valves in addition to those referenced above may be provided in some applications Refer to the wiring and piping diagrams provided with the unit for installation information Before electrically activating any section of the unit fill the indirect evaporative section s and if provided the direct evaporative section s sump with water Check the water lev el in the sump s and verify the setpoint level will not cause the sump to overflow See Drawing C000738 below for recommended float level adjustment Adjust the height of sump water fill and level control valve if necessary based on variations of water supply li
82. ould stop flashing Repeat this process so the word OFF is displayed and not flashing The Electrical Usage and Demand values have now been reset to zero and the Electrical Usage and Demand function has been rearmed Satisfaction Rating Timers Reset To reset the satisfaction rating timers the satisfied time timer and total runtime timer scroll through the menu tree locate the UNIT RESETS branch and select Satisfaction Rating Timers Reset Press the Enter key The word OFF should flash Now press the INC key and the word ON should flash on the display Press the Enter key again and ON should stop flashing Repeat this process so the word OFF is displayed and not flashing The Satisfaction Rating timer values have now been reset to zero and the Satisfaction Rating function has been rearmed Alarms Reset To reset all active alarms scroll through the menu tree locate the Unit Resets branch and select Alarm Press the Enter key The word OFF should flash Now press the INC key and the word ON should flash on the display Press the Enter key again and ON should stop flashing Repeat this process so the word OFF is displayed and not flashing The alarm has now been cleared and the Alarm RS function has been rearmed See the Menu Selection Tree for BACview section of this manual for more information about navigating the BACview menus Always change the Alarm Reset parameter to OFF after resetting the alarms If the Alarms Reset param
83. pen the pressure fittings Make sure the tubing is the Return Air Damper and close the Outside Air also clean clear of any debris and then reinstall Damper the tubes on the transducer It is very important that the High tube be placed inside the building and positioned so that air movement does not affect it The Low side should be to atmosphere and positioned so it is not exposed to the weather PT 13 SETRA P N MESTEX P N RANGE 26510R1WBABT1C 68 0330 69 1 SECTION VII TROUBLESHOOTING GUIDE continued MULTIPLEXED VOLTAGE CHART FOR INDIRECT DIRECT SYSTEMS ONLY RESISTOR SWITCH OHMS IN 399 OUTRE IN 3 SW 11 RS 04 CLG STG 2 FLOAT SWITCH 2 91 SW 10 RS 03 CLG STG 1 FLOAT SWITCH 3 43 JUMPER RS 02 NOT USED AT THIS TIME 3 61 JUMPER RS 01 NOT USED AT THIS TIME 3 67 CHECK ALL TERMINAL CONNECTIONS FOR TIGHTNESS The DC voltage is to be checked at the UC 01 board When both the cooling stage 1 and 2 float switches SW 10 amp SW 11 respectively are energized the When the cooling stage 1 float switch SW 10 is contacts will close and the VDC at IN 3 amp GND will be energized the contacts will close and the VDC at IN 3 1 87 amp GND will be 3 43 When the cooling stage 2 float switch SW 11 is energized the contacts will close and the VDC at IN 3 amp GND will be 2 91 Eras SECTION VIII MAINTENANCE SCHEDULE AND LUBRICATION REQUIREMENTS
84. r supply meets requirements turn main disconnect switch on and enable fans Damper opens if applicable Blower fan turns on Disable the fans Check supply blower for proper rotation NOTE To change rotation of the cooling fan motor controlled by motor starter simply interchange any two 2 of the line leads of the motor starter for three 3 phase motors On single phase motors refer to motor nameplate To change the rotation of any three phase motor controlled by a Variable Frequency Drive VFD interchange any two 2 of the load leads of the VFD Enable the fans Check for proper blower rpm Check that all motor amp draws do not exceed rating plate ratings and overloads are set to motor rating plate amps ed Cooling is Enabled By The Following MRT Expert or MDT Expert With A BACview KP 01 To enable the cooling scroll through the Setpoints menu in the BACview and enter the desired room Cooling Occupied and Unoccupied Setpoints If the system s airflow and static pressure are in accordance with the project specifications check for water carryover from the direct evaporative section s cooling media if applicable If carryover is observed close in small increments the water flow balancing valve provided in the direct evaporative section s recirculating pump riser until water carry over is eliminated The leaving air side of the direct evaporative media should be damp from top to bottom NOTE If adjustment i
85. ressure control varies the percentages of outside air and return air to maintain a constant pressure within the space A pressure transducer measures the pressure within the space relative to the pressure exterior to the space and transmits a corresponding signal to the Aztec DDC controller The controller compares this signal to the desired building pressure setpoint and uses a PID loop to modulate the outside air and return air dampers to maintain the specified building pressure To place the damper operation in Building Pressure mode scroll through the menu tree locate the UNIT MODES branch and select Bldg Pres Ctrl Next scroll through the menu tree locate the SETPOINTS branch select Bldg Pressure Stpt and enter the desired pressure The allowable range is 0 100 W C to 0 100 W C NOTE If the Supply Fan Operation and Mixed Air Damper Operation modes are both set to Building Pressure control the Mixed Air Damper Control mode will automatically switch from Building Pressure control to Percentage of Outside Air Control To select Building Pressure control for Mixed Air Damper Operation mode you must change the Supply Fan Operation mode to Supply Air Temperature control Percentage of Outside Air Control To place the damper operation in Percentage of Outside Air mode scroll through the menu tree locate the UNIT MODES branch and select Outside Air Ctrl Next scroll through the menu tree locate the SETPOINTS branch
86. s operation daily holiday and override The daily schedule can be programmed for up to 4 separate On Off events with any combination of days The daily schedule sets the typical On Off times for the unit D UNIT OPERATING MODES continued The holiday schedule can be programmed for up to 12 separate On Off events with any combination of days The holiday schedule sets the Off times for holidays and other shutdown periods The override schedule can be programmed for up to 2 separate On Off events with any combination of days The override schedule sets the On times that will override the holiday schedule This scheduling system allows the user to program a diverse array of On Off operations The Aztec DDC system has no preset operational schedule To set the operational times of the unit scroll through the SCHEDULES menu tree and locate the desired Daily Holiday or Override branch Enter the days and times for the unit to operate In the Daily or Override section these times should correspond to the desired on times for the unit s operation In the Holiday section these times should correspond to the desired off times for the unit s operation For any schedule to function the Use tab must be set to yes To set the time clock function for 24 hour continuous operation scroll through the menu tree and locate the SCHEDULES page Set the 24 Hr Operation to yes Enter the Daily section of the menu and set the Use tab to yes
87. s required allow sufficient time to lapse between each small incremental adjustment to the water flow balancing valve to permit stabilization of the evaporative media to the new water flow rate before making another adjustment The evaporative media may foam for a period following initial startup Leave the water bleed off valve fully open until the foaming ceases The water bleed off valve can then be re adjusted to approximately 3 6 of the evaporative media s water recirculation rate The actual amount of bleed off required is dependent on the quality of water used and the rate of evaporation As climate conditions change the rate of evaporation may increase thereby requiring an increase in the bleed off rate It is recommended that the bleed off rate be set for the condition of maximum water evaporation An indication of insufficient bleed off is a uniform buildup of minerals on the entering air face of the evaporative media If this condition is observed increase the rate of bleed off until the mineral deposits dissipate Repeated drying of the cooling media will also cause the rapid buildup of insoluble deposits Cooling Tower Setup The water flow for cooling tower has been factory set and should require only minimal adjustments in the field Use same steps for adjusting water flow bleed off rate and initial foaming as listed above for direct evaporative section The water flow over the cooling tower media is intended to be
88. select OA Setpoint and enter the desired percentage open for the outside air dampers The damper actuators will drive the outside air dampers open to the Min OA setpoint or the 96 OA setpoint whichever is greater Automatic Economizer The unit operates in economizer mode when the outside air dry bulb temperature is below 65 F and the outside air enthalpy is below 25 btu Ib m Once these conditions are satisfied the outside air dampers begin to modulate open to provide free cooling in the space The outside air temperature economizer setpoint and outside air enthalpy economizer setpoint are adjustable via the SETPOINTS branch of the menu tree in the BACview The DDC controller calculates the outside air enthalpy automatically based on the outside air dry bulb temperature and the outside air relative humidity The automatic economizer overrides mixed air temperature control and percentage of outside air control but does not override building pressure control or the 100 outside air function 100 OUTSIDE AIR The 100 Outside Air function automatically opens the outside air dampers and closes the return air dampers This function is activated whenever a contact is closed between the appropriate terminals on the unit s terminal strip located in the unit s main control panel See the Typical Wiring Schematic and Multiplexed Input sections of this manual for more information The 100 Outside Air function overrides all other
89. ses the device instance number can also be accessed via the modstat function for example Device Instance 0024016 Unit Setup HOTKEY 9 e Control System o MRT modulating room temperature o MDT modulating discharge temperature SA Temp Ctrl PID P Gain SA Temp Ctrl PID I Gain SA Temp Ctrl PID D Gain SA Temp Ctrl PID Interval Bldg Pres Ctrl PID P Gain Bldg Pres Ctrl PID I Gain Bldg Pres Ctrl PID D Gain Bldg Pres Ctrl PID Interval Mxd Air PID P Gain Mxd Air PID I Gain Mxd Air PID D Gain Mxd Air PID Interval Econ PID P Gain Econ PID I Gain IN N MENU SELECTION TREE FOR BACVIEW continued Econ PID D Gain Econ PID Interval e 2nd Clg Stage Installed No Yes e Current Xducer Range 0 200 amps o of Wire Wraps o Volts o 3 Phase No Yes Login Home e Userpw NOTE PID loop settings are only visible on the Unit Setup screen when logged into the BACview as an Admin When logged in as a User the PID Unit Modes HOTKEY 2 e Auto Off Manual Auto o Off o Manual Zone Temp Type o Aztec Supplied 3rd Party e Supply Fan VFD Mode o SATemp Control o Bldg Pressure Control e MA Damper Mode o Bldg Pressure Control o MA Temp Control Outside Air Control loop settings will not be visible but the other Home configuration items will be e Stpnts Status e Alarm Unit Setpoints HOTKEY 3 ITEM RANGE Occ Zone
90. sy to move the BACview between the location of the room sensor in the space and the unit s location without having to do any additional wiring Simply unplug the BACview from the bottom of the room sensor in the space and take it to where the unit is located Then plug the BACview into the Local Access Port on the controller as shown in Figure 1 To go from where the unit is located to the room sensor in the space unplug the BACview from the Local Access Port and take it to the room sensor Then plug the BACview into the bottom of the room sensor For MDT and MDT Expert systems simply plug the BACview into the Local Access Port on the controller as shown in Figure 1 as a room sensor is not provided with these systems If there are multiple units at the jobsite the BACview can easily be unplugged from one unit and plugged into another For this reason it is not recommended to hardwire the BACview into the Rnet port on the left hand side of the controller because it sacrifices the convenience of portability Operational modes include time scheduling filter monitoring and multiple damper control and temperature control schemes All of these modes provide the maximum in unit operational flexibility The diagnostic capabilities of the Aztec DDC system ensure swift response to abnormal unit conditions An alarm is generated anytime a conflict exists between the operational parameters and actual unit operation An indication of trouble
91. tch on the electrical schematic and identify the control panel terminals to which it is connected Disconnect the wire from these terminals D Cooling Stage 1 Maintenance This alarm requires a manual reset once it has been acknowledged by the operator The runtime for cooling stage 1 has surpassed the cooling stage 1 maintenance trip setpoint default value is 2 200 hours user configurable via the BACview Refer to the Aztec Installation Operation and Maintenance IOM Manual for a complete list of maintenance procedures and the recommended maintenance schedule Conduct any required maintenance to ensure continued efficient operation of the unit This includes following the procedure in the IOM Manual for removing mineral deposits from the evaporative media and checking the piping for leaks as well as ensuring that all electrical components are operating correctly and that wires are connected securely to the correct terminals Reset the alarm hotkey FN MUTE on the BACview E Cooling Stage 2 Maintenance This alarm requires a manual reset once it has been acknowledged by the operator The runtime for cooling stage 2 has surpassed the cooling stage 2 maintenance trip setpoint default value is 2 200 hours user configurable via the BACview Refer to the Aztec Installation Operation and Maintenance IOM Manual for a complete list of maintenance procedures and the recommended
92. tent of damage Upon inspection of article make claim to the delivering carrier Concealed Damage In Transit Sometimes transit damage is not noticed until the goods are unpacked In such cases notification to the carrier must be made within fifteen 15 days of receipt of shipment In such cases save the packages and packing material then notify the transportation company at once and request an inspection When the inspector calls have him make out and leave a concealed bad order report He is obliged to give one to you Insist on it Disposition Of Damaged Articles Never return damaged articles to us They are the property of the transportation company when the claim is filed They will give you disposition instructions Packing We comply with the packing requirements of the transportation companies and your bill of lading proved that everything was in good condition when shipped That bill of lading contract requires them to deliver in perfect condition SECTION II GENERAL INFORMATION A Purpose The purpose of this manual along with the burner IOM if applicable is to present a guide for proper installa tion maintenance and operation of the Indirect or Indi rect Direct Evaporative Cooling System and to supple ment but not to replace the services of qualified field service personnel to supervise the initial start up and adjustment of the unit Persons without previ ous experience with large commercial and i
93. tery provides a minimum of 10 000 hours of data retention during power outages Remember to check the battery periodically once a month or so to verify that its voltage is approximately 3 VDC If the voltage is not approximately 3 VDC replace the battery so that the controller s program is not lost during a power outage Loss of the program will require the controller to be shipped back to the factory for reprogramming because the unit will not function without the program Make sure the controller is powered any time the battery is removed or the controller s memory may be lost Figure 2 shows the location of the battery on the controller 48 Check once a month to verify that the charge of the battery is 3 VDC l n r a mm f NET m Figure 2 APPENDIX IV Typical Wiring Schematic K H B by 2 1 i E i JE uii X m ii B E 18 iH m i i gc BACnet Flex 6126 NE RTD 24 50 50 He CONTROL MODULE Therm OVA 0 83 Use Copper 0 20n Mode Conductors Ony Even 044 Select 201 Swiches Network 05 off 1 on P tocd 8 2 m 00 5 MSTP 9 Mi Modus SLTA Plugin Ethemet AO Mode Select sar E Net4Tx Tx Re 3 Expansion nic Ref OTR nic Ir loco unused Signal Ground
94. tion 11 General Information 3 Section Installation eeeeeeeeeeeese 4 Section IV Pre Start 9 Section V Unit Start 10 Section VI Unit Shut 11 Section VII Troubleshooting Guide 12 Section VIII Maintenance Schedule and Lubrication Requirements 18 Section IX Replacement 20 Section X Aztec DDC System User Manual 21 IMPORTANCE NOTICE Aztec assumes no responsibility for loss or damage in transit therefore you should protect yourself by following these instructions Bill Of Lading Save your bill of lading It is a contract and you will need it provided you have to file a loss or damage claim Remember claims are outlawed after nine months Loss In Transit Before you sign for this shipment check against the bill of lading also the transportation company s delivery ticket Make sure that you get the exact total of articles listed Should the delivery ticket show more or less items than are offered then the carriers agent must mark the difference on your freight bill before you sign Visible Damage In Transit If anything is damaged accept the shipment only if the carrier s agent places a notation on your freight bill explaining the nature and ex
95. to insure that all crimped connections are tight 5 Check set screws on all fans for tightness 6 Check voltage supplied to disconnect switch the maximum voltage variation should not exceed 10 Phase voltage unbalance must not exceed 2 7 Check thermostat s for normal operation 8 Check to ensure all manual reset safety devices have been reset and limits are in the normal operating position 9 Check that system duct work is installed and free from obstructions 10 Check that fans turn free in housing 11 Check that the area and around the unit is clear of debris or containers of flammable liquids 12 Check that all piping connections particularly unions are tight and installed correctly 13 Check that all accessories requiring field wiring have been properly installed and wired 14 Check that filters filter stops accessories and ship loose items are installed correctly 15 Motor overload relay setting if applicable should match the motors nameplate full load amperage 16 Check that dampers and linkages are free to move and that linkages are tight 17 Do not run the pump without water in the sump of the indirect evaporative section cooling tower and if provided the direct evaporative cooling section 18 All float and liquid levels and bleed off rate are pre set at the factory during final equipment testing and quality control inspection However these settings should be verified at the job site
96. top output BO 1 is energized 2 Controller s supply fan start stop output BO 1 is shorted 3 The unit enable relay RE 57 and or main airflow switch PS 10 is energized 4 Main airflow switch s PS 10 normally open contact is closed 5 Continuity at the controller between the fan status terminals 226 and 227 If the fan is not running 1 Main airflow switch s PS 10 normally open contact is closed 2 There is a short in the wiring between the fan status terminals 226 and 227 There is a problem with the controller Contact factory Contact factory There is a short in the wiring Determine cause and rectify Replace main airflow switch There is a short in the wiring between these terminals Determine cause and rectify Replace main airflow switch Determine cause and rectify Unit On Fan Off The controller has activated the unit enable output to start the fan but the fan status input is not receiving a signal that the fan is running This alarm resets automatically once this conflict is resolved If the fan is running 1 The BACview is indicating that another existing alarm condition is preventing the fan from running 2 The unit enable relay RE 57 and or main airflow switch PS 10 is energized 3 Main airflow switch s PS 10 normally open contact is closed 4 There is an open in the wiring between the fan status terminals 226 and 227
97. vember 18th to Saturday November 24th We want the unit to operate each weekday from 8 00 AM to 12 00 PM while the maintenance crew is in the building during this week We will need to set up a few Holiday schedules to accomplish this Since the unit normally runs from 6 00 AM to 5 00 PM on weekdays we need to set the Off periods in the Holiday schedules The Off period we want to schedule then is from 6 00 AM to 8 00 AM and 12 00 PM to 5 00 PM We will use 10 Holiday schedules to accomplish this two for each weekday 7 Navigate back to the Schedules screen using the FN 7 hotkey Move the cursor to select the Holiday field and press Enter Set the start time to 6 00 AM and the stop time to 8 00 AM Remember the Holiday schedules represent the period during which the unit is to be OFF Set the Month field to 11 November and the Day field to 19 Monday the first weekday that week Your screen should now look like this Holiday Sch 1 Use YES Stat ON 24hr Sta rt Time 6 0 Stop Time 8 0 Month 11 1 12 Day 19 1 31 Prev Next gt Home LOGOUT UNIT OPERATING MODES continued 8 Press the link key corresponding to the Next field on the screen This will take you to Holiday Schedule 2 Set the start time for Holiday Schedule 2 to 12 00 PM and the stop time to 5 00 PM Set the Month field to 11 November and the Day field to 19 Monday the first weekday that week Your screen should now look like t
98. wer fan motor thereby increasing the evaporative cooling effect of the media As the supply air temperature falls below setpoint the controller signals the VFD to decrease the speed of the cooling tower fan motor Then the cooling tower fan motor and cooling outputs are disabled until a call for cooling is present again The cooling tower fan VFD will approach its minimum speed as the supply air temperature approaches the minimum supply air temperature setpoint The cooling tower fan motor and cooling outputs are disabled until a call for cooling is present again Manual Override The administrator password for the BACview is required in order to use the manual overrides The supply fan VFD analog control output AO 2 and the cooling tower fan analog control output AO 3 can be controlled manually via the OVERRIDES branch of the BACview menu tree by adjusting the speed of each fan motor as a percentage of full speed First set the desired supply fan speed percentage Then toggle the Lock SF VFD AO 2 field to YES The controller will now force the supply fan VFD to drive the supply fan motor at this percentage of full speed until the Lock SF VFD AO 2 field is toggled to off The same process can be repeated for the cooling tower fan analog output AO 3 if the unit is equipped with the optional cooling tower VFD WARNING Manually overriding the supply and cooling tower fan motor analog outputs disables automatic motor spe

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