Lochinvar Electric Hot Water and Steam Boilers User's Manual
Contents
1. 8 C BOILER ELECTRICAL SYSTEM MAINTENANCE Clean the boiler periodically as often as needed to keep both the interior and the exterior free of dust moisture and foreign matter The interior clean ing of the electrical panels must be done with the POWER OFF 8 C 1 NOTE For units supplied with control cabi Net cooling fans the condition of the fan filter must be periodically checked and the filters cleaned or replaced as necessary 8 C 2 With the POWER OFF periodically check the tightness of electrical con nections particularly at power entrance lugs fuses line side and contactors load side Chapter 8 7 Chapier 8 8 C 3 8 C 4 8 C 5 8 D 8 D 1 8 D 2 Inspect the condition of the contactors Look for burned or corroded contacts or overheated coils and wires If the con tactors chatter or hum during operation they should be disassembled and cleaned to remove dust or other foreign material in the works or replaced if needed Inspect the heating elements Make sure that the terminal contacts are tight clean and corrosion free Check ail the wiring throughout the boiler for frayed or brittle insulation Replace any wiring having exposed metal parts BOILER MECHANICAL SYSTEM MAINTENANCE With the POWER OFF remove the ele ment access covers Inspect all inter nal plumbing connections particularly at the heating elements Spot check torque on element flange bolts The acce2. every 2 F change at the outdoor sensor will cause an automatic inverse change of 1 F NOTE Refer to the applicable vendor litera tth trol point ture provided on both the setpoint controls and PEMD SRIIQSEOINS step controls installed in your boiler Chapter 7 2 N Page 16 Chapter 8 PREVENTIVE MAINTENANCE 8 A GENERAL Electric immersion heating element boilers are automatic quiet and safe Conse quently they are all too often neglected Like any piece of electrical mechanical equipment they require care and mainte nance to keep them in top working condition If electrical connections are allowed to be come loose or dirty there is danger of an electrical fault If the elements are not In spected periodically for leaks the water from leaking elements can leak onto adja cent elements causing external element damage and resulting in the blowing of load fuses in the boiler electrical panels If the boiler water is not properly treated ele ment failure could occur due to the forma tion of scale Treat the boiler with respect CAUTION Always work on the boiler with all electrical disconnected power sources Page 17 8 B WATER TREATMENT Boiler water should be periodically checked through a sampling procedure Properties should be maintained in accord with TA BLE 8 1 at the end of this chapter For consultation relative to water treatment please contact a reputable water treatment firm
3. Outlet Water Temperature or Steam Pressure NOTE Outdoor reset dual bulb controllers are set at the temperature at which the boiler should operate when the outdoor temperature is 70 F this outdoor reference temperature is adjustable on most solid state controls fixed on Honeywell T991B controllers The reset ratio fixed on Honeywell T991B type adjust able on Honeywell T775J is the number of degrees the boiler control temperature will in crease for a 1 degree decrease in outdoor temperature 5 A 1 c Throttling Range The throttling range is the number of degrees or psi the outlet water temperature or steam pressure must change to drive the step controller from full off to full on Page 11 5 A 2 A 3 For instance if the controller is set at 160 F and the throttling range is set for 10 F the step controller will be full on at 155 F 1 2 of throttling range below setpoint and full off at 1C5 F 1 2 of throttling range above setpoint The more stable the load on the boiler from system de mands the smaller the throttling range may be set High Limit Temperature or Pressure Set the automatic reset high limit 10 F or 5 psi or twice the throttling range whichever is greater above the setting of the controller Manual reset limits should be set slightly higher than the automatic reset limits For steam boilers the manual reset high limit should be set at least 10 below the
4. be maintained at 70 F simply set the control ler at a temperature equal to the actual outlet water temperature to perform this test Chapter 7 7 N Chapter 7 OPERATIONAL TESTING EXAMPLE SETTING THE TEMPERATURE CONTROLLER Reset Ratio 1 1 1 2 ie 2 3 1 Outdoor Temperature 40 F Boiler Water Temperature 130 F STEP A Difference between outdoor temp and 70 F 70 40 30 F STEP B Multiply 30 F times the Reset Ratio 2 3 30 x 2 3 20 F Subtract 20 F from the Boiler Water Temp 130 F 130 20 110 F STEP C Set the Controller at 110 F NOTE If the Outdoor Temperature is above 70 F add the difference in STEP A multiplied by the Reset Ratio to the Boiler Water Temperature 7 B 2 Solid State Dual Input Example cae pieni E a inca Assume a reset ratio of 2 1 a primary set Honeywel sides point of 100 F and a secondary setpoint W7100J Sequencers at 70 F The first number of the reset ra These are dual sensor reset controllers with tio indicates change in outdoor tempera adjustable reset ratio and outdoor reference ture the second the change in the temperature The reset ratio is the ratio of control point If the outdoor temperature the change in the temperature at the secon drops from 70 F to 20 F a change of 50 dary sensor to the opposing change in the F the control point will increase from control point If the reset ratio is 2 1 then 100 F to 125 F a change of 25 F
5. is to direct a heat lamp at the suspect element or remove the element bake it in a 200 F oven for 8 hours then reinstall and rewire After completion of either of the above Methods for moisture removal recheck the Element with a megger When the reading indicates an acceptable level the element may be put in operation by replacing the fuses Replace of Element Access Panel s and close electrical control panel doors Chapter 4 32 PRE STARTUP INSPECTION 4 E INSPECTION POWER VOLTAGE 4 E 1 Verify the boiler ON OFF control switch is in the OFF position Close the boiler main power switch switch the control switch to ON and then 4 E 1 a Check the phase to phase voltage at the main terminals in the boiler electrical panel The phase to phase voltage between any two of the phases must not exceed the boiler nameplate voltage 4 E 1 b Check the voltage at the boiler con trol circuit fuse It should be be tween 105 volts and 125 volts 4 E 1 c Open the boiler main power switch 4 E 2 If all of the above prove satisfactory proceed with Startup Instructions Replace all covers and close all doors Page 10 Chapter 5 STARTUP INSTRUCTIONS 5 A CONTROL SETTINGS 5 A 1 Controller See Parts List for Part No and Type 5 A 1 a The controller is the pressure or temperature sensing device which controls the operation of the step control 5 A 1 b Set the Controller for the desired
6. phase wires to new element When boiler is filled and pressurized check for leaks FEEDWATER Type of Boiler Hardness pH Oxygen Total Dissoived Solids ppm ce 1 TDS ppm Hot Water 0 10 7 5 9 5 4 0 0 500 Steam 0 5 7 5 9 03 0 350 Type of Boiler Hardness pH BOILER W Total Dissolved Solids ppm cc 1 TDS ppm Hot Water 0 10 7 5 9 58 0 5000 Steam o 7 5 9 5 Oo 0 3500 Page 19 The limit of 9 5 pertains to copper elements a pH of 10 5 is allowable for Incoloy elements Chapter 8 3 Chapter 9 WARRANTY amp RETURNS 9 A ASSISTANCE Furnish Complete Information Before calling the LOCHINVAR Agent or the Factory with questions concerning boiler operation needed parts or warranty please be sure to have the information readily available that is stamped on your Boiler s Data Plate see Data Plate details below FIGURE 9 1 All files are maintained by Serial Number so please have this number available when corresponding about your boiler All or der s should state the Manufacturer s part number if known and the name and de scription of the part required Also state the quantity desired and specify the method of shipment 9 B PART ORDERS Repair or replacement parts for LOCHIN VAR boilers may be ordered through the LOCHINVARAgent in your area You may also contact the
7. safety valve set pressure Low Water Cutoffs These cutoffs are always factory set If additional cutoffs are field installed the cut off levels should be at least three inches above the highest heating ele ment Manual reset cutoffs should be set below automatic reset cutoffs Chapter 5 7 Chapter 5 5 4 4 Low Limit Sensors Temperature or Pressure Low limits should be set below the con troller setting by at least the same mar gin as specified for high limits to be above the controller setting 5B OPERATING INSTRUCTIONS 5 B 1 With the boiler main power ON OFF or ON OFF PREHEAT switch OFF close the boiler main power switch Close the boiler disconnect switch if provided NOTE Boilers with shunt trip disconnects and remote 120 volt control power may require turning the boiler control power switch ON and activating the 120 volt power before clos ing the boiler main power switch es 5 B 2 Electric Door Interlocks For boilers equipped with electric door interlocks do not attempt to open clec trical panel doors after the main switch is closed The lock tabs are mechani cally restrained by the electric interlocks 120 Volt Power Source lf a separate 120 volt power source is provided close its disconnect switch 5 B 3 Turn the boiler main power ON OFF or ON OFF PREHEAT switch to ON 5 B 4 5 B 5 Alarm and Reset Circuits 5 B 5 a If the alarm sounds when the con trol switch is t
8. ATIONS Consult local building and safety codes be fore proceeding with work The operation of this equipment by the owner and his op erating personnel must comply with all re quirements or regulations of the authorities having jurisdiction In the absence of such authorities the in Stallation must conform to the safety codes set forth by the American Society of Me chanical Engineers ASME 1 C RECOMMENDATIONS 1 C 1 Preventive Maintenance A Preventive Maintenance Schedule is pro vided as a recommendation for periodic boiler inspections Recording of daily weekly monthly and yearly maintenance activities as well as the recording of any unusual operation will serve as a valuable guide to any necessary investigation The standard Limited Warranty does not cover any damage caused by lack of re quired maintenance Page 2 Chapter 1 INTRODUCTION 1 0 2 NATER TREATMENT Feedwater and Boiler Water Properties should be maintained in accordance with the table provided in this manual It is cus tomary to engage the services of a qualified water treatment consultant to recommend the proper water treatment program Damage from scaling corrosion or erosion attributed to improper treatment of boiler water is not covered by the standard Lim ited Warranty i Chapter 1 2 Page 3 Chapter 2 STORAGE amp HANDLING 2 A RECEIVING 2 D PLACEMENT Each LOCHINVAR boiler is completely in spected at t
9. D Mechanical System Maintenance E Element Replacement Procedure CHAPTER 9 WARRANTY amp RETURNS A Assistance Figure 9 1 Data Plate B Part Orders C Repair Procedures D Warranty Return Procedures E Limited Warranty CHAPTER 10 ADDITIONAL INFORMATION A Boiler Parts List and Schematics B Vendor Literature C Troubleshooting D Factory Startup Checklist E Recommended Spare Parts Chapter 1 INTRODUCTION 1 A GENERAL INFORMATION This LOCHINVAR Electric Hot Water and Steam Boiler Operation and Maintenanco Manual presents information that will help to properly operate and care for the equipment Study the contents carefully The unit will pro vide good service and continued operation if proper operating and maintenance instructions are followed The standard Limited Warranty does not apply to boilers not installed or oper ated in accordance with these procedures LOCHINVAR boilers are designed and engi neered to provide excellent service and to give long life on the job Although the unit and its components afford a high degree ot protection and safety operation of the equipment is not to be considered free from hazards inherent in the handling of electricity and pressurized hot water or steam Pay close attention to WARNINGS and CAU TIONS as these present situations of potential hazard and remember no amount of written instruction can repiace intelligent thinking and reasoning Chapter 7 1 B LOCAL REGUL
10. Factory directly at the ad dress or phone number listed on the back of this manual Refer all inquires directly to the Parts Department 9 C REPAIR PROCEDURES Parts to be repaired should be returned freight prepaid to the address indicated on the back of this Manual Please indicate the urgency of the repair FIGURE 9 1 Mea SERIAL O Kw A 1 Kime lav EEA LA Chapter 9 1 NAT L BD Max W Pk 5 V R CAP ouea DEA emm e DATE i Page 29 Chapter 9 9 C WARRANTY RETURN PROCEDURES A purchase service order or a letter authorizing repairs showing Model Num ber and Serial Number of the Boiler and giving complete details should be mailed to the address listed on the back of this manual Please include inside the pack age a packing slip identifying the parts with your company s name Return shipment must be freight prepaid Freight collect shipments will not be accepted 9 D PRECISION LIMITED WARRANTY The Limited Warranty was shipped with the Boiler and thoroughly identifies the period items covered and terms of the Limited Warranty Parts being returned for replacement or repair covered WARRANTY amp RETURNS under the warranty as defective must be identified and accompanied by a Return Goods Authorization RGA RGA s are available from the Factory Service Department When defective goods are returned with the appropriate information either a re placement or
11. High Efficiency Water Heaters And Boilers The Built In Advantage Lochinvar Corporation Nashville TN 615 889 8900 FAX 615 885 4403 www Lochinvar com Electric Hot Water and Steam Boilers OPERATION AND MAINTENANCE MANUAL WARNING A complete understanding of this manual is required before attempting to operate or maintain the equipment Improper installation adjustment alteration service or maintenance can cause injury or property damage The equipment should be operated and maintained only by personnel who have read this manual and who have a working knowledge and understanding of the equipment Ee Oe E These instructions are intended as a guide for the Installing Contractor and as a reference for the Operator Owner and Serviceman RETAIN THESE INSTRUCTIONS NEAR THE EQUIPMENT FOR READY REFERENCE The instructions contained in this manual are intended as a guide only and do not supplant any National State or Local Codes This unit must be installed in accordance with those installation regulations in force in the local area where the installation is to be made These shall be carefully followed in all cases installation is made Authorities having jurisdiction shall be consulted before LOCHINVAR has a commitment to product improvement and continually strives for the highest standards of product performance In pursuing this policy of continuous development of products the manufacturer reser
12. al limit switch In order to preheat the boiler the ON OFF PREHEAT switch must be in the down position When the ON OFF PREHEAT switch is in its down or PREHEAT position the boiler output is lim ited to approximately 25 of full load power This allows the operator to limit the boiler output during startup cycles particu larly if the boiler is shut off at night and turned on again in the morning which could lessen electrical demand charges When the boiler has been brought up to the setpoint temperature or pressure the ON OFF PREHEAT switch is moved slowly from its down or PREHEAT position to its up or ON position passing through the OFF position to cause the control to recycle to the NO LOAD position Thereafter the boiler can operate up to full load if necessary NOTE The PREHEAT switch is included as standard equipment on boilers of 9 or more steps It is intended to be used to prevent set ting demand peaks on cold starts It does not have to be used if so desired Page 44 Chapter 7 OPERATIONAL TESTING 7 A STANDARD CONTROLS 7 A 1 135 ohm Controllers T991 T915 L91 etc With the boiler water temperature or steam pressure at setpoint the step con troller should bring on nominally one half of the steps An adjustable proportional band is provided on the controller sensor to en able tuning the boiler to system demand 7 A 2 Solid State Controls With the boiler water temperature or pr
13. eed 3500 PPM 8 D 7 b Both the boiler and water column should be blown down periodically to remove bottom sludge 8 D 7 c The water column should be blown down daily to assure proper opera tion of the level contro LWCO assembly Page 13 Chapter 8 8 D 7 d Water Treatment Water treatment is required for satisfac tory operation of steam boilers to prevent both deposition of scale and corrosion from acids oxygen and other harmful elements that may be in the water sup ply A qualified water treatment specialist should be consulted to establish a proper water treatment program ELEMENT REPLACEMENT PROCEDURE 4 Bolt Style Element 8 E CAUTION Before element replacement make cer tain main power to boiler is turned off that there is no pressure in the boiler and that boiler is drained below element opening TABLE 8 1 Recommended Feedwater and Boiler Water Properties PREVENTIVE MAINTENANCE NOTE To prevent hazardous conditions of leaking water steam at the element terminal ends defective elements or element gaskets should be replaced immediately upon leak de tection 8 E 1 Adequately tag wires and then remove wires from defective elements 8 E 2 Remove element by removing the 4 four attachment nuts 8 E 3 Install replacement element with new gasket and torque nuts to 10 15 ft Ibs WARNING Do not exceed 15 ft Ibs 8 E 4 8 E 5 Connect
14. es sure at setpoint the step control should bring on nominally one half of the steps Adjustable time delays between steps and adjustable proportional bands are normally provided on the step control to enable tun ing the boiler to system demand solid state controls also include band width adjustment at the control itself and nor mally include PID control action 7 B OUTDOOR RESET CONTROLS 7 B 1 135 ohm Type Outdoor Reset Controller Honeywell T991B type These controllers have a fixed reset ratio either 1 to 1 1 to 1 5 or 1 5 to 1 Page 15 Most The outdoor reference temperature is 70 F ie the boiler outlet water control point temperature is equal to the setting on the controller when the outdoor temperature at the outdoor bulb is 70 F In order to test the operation of this controller 7 B 1 a Check the outdoor temperature at the outdoor air sensing bulb then determine the number of degrees this temperature is above or be low 70 F Check the boiler outlet water tem perature if the outdoor tempera ture is below 70 F multiply the difference between 70 F and the actual outdoor temperature by the reset ratio 1 0 67 or 1 5 and subtract this from the temperature of the boiler outlet water 7 B 1 b Then set the controller at this re sultant temperature the step con troller should maintain nominally half of the steps on 7 B 1 c NOTE If the outdoor bulb is at 70 F or can
15. he factory and carefully pack 1 CAUTION aged for shipment Upon receipt of the If the boiler is to be placed in a room with shipment immediately inspect the packing little or no ventilation a supply of ducted for signs of exterior damage Verify receipt filtered air may have to be brought to the A A z low ortio the control cabinet t of 4 packages listed on the packing slip imit the Entiat ak eee Advise the carrier of any shortage or dam ture to 50 C 122 F maximum age Any such claims should be filed with the carrier The carrier not the shipper is responsible for shortages and damage to 2 D 4 Provide a firm level foundation for the the shipment boiler 2 B STORAGE NOTE Standard electric boilers are not suit able for placement on combustible flooring Electrical equipment can be damaged if ex posed to adverse weather The boiler should be stored inside The electrical panel and controls should be covered with plastic throughout all construction to avoid accumulation of dust and moisture on the controls and load components The contac tors can be damaged by dust dirt in the mechanism 2 D 2 Leave a permanent space for element removal opposite element access pan els as shown on the Dimensional Drawing DD and 36 inches opposite electrical panels NOTE 42 is required opposite electrical pan els if the opposing surface is conductive 2 D 3 Be sure to keep electrical panels and 2 C UNCRATING controls co
16. hipment or installation Remove one of the boiler control cir cuit transtormer primary fuses Then check the resistance phase to phase for all three phases Make sure that there are no short circuits phase to phase or phase to ground With a megger 500VDC minimum check contactor load side terminals to ground If a reading of lt 1 me gohm is obtained consult the LOCH INVAR Agent or Factory Replace the control transformer fuse which was previously removed Remove element access panel s and open the doors to the electrical control panel s Run an inspection of the tightness of all electrical con nections ie at fuse lugs power en trance lugs contactors heating elements Page 3 Chapter 4 04 C 4 04 6 5 Page 9 All branch circuit connections should be tightened to 35 40 inch Ibs torque to avoid component damage from heat build up This tightness inspection is vital be cause the vibration during shipment can often loosen electrical connec tions If this is not done damage may occur to component parts when power is switched on and those damaged parts will not be covered under the manufacturer s warranty With an ohmmeter check the resis tance between the phases on the load side of the contactors Each should read the same and approxi mately what is shown on the wiring diagram Check the electrical panels for loose material dust and or moisture Thoroughly vacuum the panels if dus
17. is the power to an ele ment circuit is supplied through the contacts of a contactor The contactor is activated on a call for heat by the closure of a temperature or pressure switch or by a contact in the step control circuit 6 A 2 Fuses All power leads to the elements are fused The fusing is on the line side of the contactors 6 B SEQUENCING CONTROLS 6 B 1 Staged Control Circuit 6 B 1 a In this type of circuit the contactor coils are energized directly by the contacts of immersion thermostats or pressuretrols There is usually one thermostat or pressuretrol for each stage or a multi stage ther mostat or pressuretrol may be provided in some cases 6 B 1 b The safety limit devices high tem perature low water etc interrupt the power to the contactor coil circuits Page 13 6 B 2 Proportional Step Controls 6 B 2 a Step Control Sequence The controller senses the boiler water temperature either via 135 ohm device or thermistor or the boiler steam pres sure either via 135 ohm device or 4 20ma transducer The output signal of the controller causes the step control to sequence the steps on or off depending on whether the boiler output is below or above setpoint When one of the switches closes on the step control a contactor coil or coils is energized in a step wise fashion This type of step control will mid position bring on half of the steps when the boiler water temperature or steam
18. ler vessel Normally the only remov able threaded connection is the boiler drain pipe DO NOT ATTEMPT TO REMOVE ANY OTHER PIPING 3 A 2 Install the safety relief valve s on the pipes provided Plumb the relief valve outlet connections full size to the floor drain Check local codes for proper safety valve discharge for steam boilers above 15 psi which normally are re quired to be piped to overhead dis charge outside safely away from personnel Chapter 3 1 3 A 4 3 4 3 Hot water boilers may be equipped with an air vent pipe on the top of the boiler Plumb this connection to the expansion tank or install an automatic air vent on this pipe The direction of flow through hot water boilers must be from the inlet to the outlet ie bottom to top Do not re verse these connections NOTE Do not oversize feedwater piping and valves on steam boilers as this may result in severe pressure fluctuations during feedwater cycles if the fill rate is too rapid 3 B ELECTRICAL CONNECTIONS 3 B 1 Power Feed Wiring The recommended wire size is listed on both the boiler Bill of Materials BOM and the Wiring Diagram WD Also the full load amperage and maximum voltage are listed on both the Bill of Materials and the nameplate Feed wires must be rated for the voltage and 125 of the full load am perage according to Article 424 3 of the NEC The wiring must be insulation rated 75 C or greater Copper wiring is recom
19. mended for all power connections Page 6 Chapter 3 INSTALLATION 3 C FILLING THE SYSTEM 3 C 1 The system and the boiler must be thoroughly flushed before the final fill Steam boilers should be boiled out before operation CAUTION Do not exceed the maximum voltage as listed on the nameplate 3 B 2 Equipment Grounding 3 C 2 Water Treatment Conductors Consult a local water treatment firm for The boiler is equipped with grounding lug s recommendations on proper water treat insid the power panel s The grounding ment and boilout procedure to prevent conductors must be installed and sized in damage to the boiler vessel components accordance with NEC Article 424 14 The and heating elements recommended size is noted in the Notes on Ihe internal materials ot the boiler are the wiring diagram Steel Incoloy and Cast Iron which all are compatible with standard boilout com 3 B 3 Control Wiring 4 n f pounds In lieu of a commercial boilout Alteration of or additions to control wiring compound the following mix of chemicals may void the Underwriters Laboratories can be used for every 1 000 gallons of Listing and the Manufacturer s Warranty water Field installed controls contro connections 30 Ibs tri sodium phosphate Na PO and modifications must be approved in writ 5 Ibs caustic soda NaOH ing by LOCHINVAR 2 Ibs ordinary detergent These chemicals should be dissolved in warm water prior to their additi
20. on to the boiler The boiler should be heated for at least 3 hours then drained and flushed NOTE All power connections to LOCHINVAR boiler s are 3 Phase 3 Wire Exception If boiler is single phase There is no provision for a neutral connection ie the boiler should not be wired wye or star NOTE Standard hot water boilers are suit able for ethylene glycol mixtures up to a 50 50 mix Chapter 3 2 i Page 7 Chapter 4 PRE STARTUP INSPECTION 4 A AwONA gt 4 B MINIMUM EQUIPMENT REQUIRED FOR STARTUP AND TROUBLESHOOTING Volt Ohm Meter Clamp On Ammeter Megohm Meter Torque Wrench inch Ibs Torque Wrench foot Ibs MECHANICAL SYSTEM CHECKS 4 B 1 Plumbing Connections Completed 4 B 4 B 4 B C Inlet Makeup water C Discharge Outlet O Drain Blowdown C Relief Safety Valve discharge 2 Feedpumps Circulating Pumps for proper rotation with water 3 System Flush C Has the System been flushed struction debris 4 Valves 0 Are all valves in the proper open or closed positions Chapter 4 1 o Pumps wired connected and checked C Is the boiler filled to the proper level L Has the unit been cleaned of all con 4 C ELECTRICAL SYSTEM CHECKS With boiler main power switch es OFF and locked out O4 c 1 O4 2 O4 c 3 Inspect all components external and internal to assure that there has been no damage during s
21. pres sure is at setpoint For example an 8 step steam boiler with the pressure controller set at 12 PSIG will have 4 steps on when the boiler steam pressure is at 12 PSIG 6 B 2 b Progressive Sequence Step Controls These controls are provided as standard and include Selectronix SLC series Solitech M72 series and Honeywell W7100J series They provide first on first off staging of the element circuits Chapter 8 1 Chapter 6 As the boiler temperature or pressure drops below setpoint the control brings on more steps As the temperature or pressure increases and approaches set point the step control drops out stages The first step to drop off is the one that has been on the longest This provides even usage of the system s components 6 B 2 c Linear Sequence Step Controls This type of step control is limited to the Solitech M72 In this sequence progres sion the control applies power by pro gressing from Step 1 to the maximum number required to satisfy the load and then decreases power by retracing this sequence down toward the first step NOTE Refer to the applicable vendor litera ture provided on the step control installed in your boiler 6 B 3 Recycle Feature All step controls now incorporate the recy cle feature which returns the step control to the no load condition upon loss of control power Chapter 6 2 SEQUENCE OF OPERATION 6 B 4 Preheat Switch The preheat switch is a manu
22. ptable torque range is 10 15 ft Ibs CAUTION DO NOT OVERTIGHTEN ELEMENTS Remove and replace any leaking ele ments or element gaskets Inspect handhole and manhole gaskets If these gaskets are brittle they should be replaced WARNING Over torqueing of the element nuts will damage the element gasket Chapter 8 2 PREVENTIVE MAINTENANCE 8 D 3 Repair any leak at any place on the boiler or adjacent piping 8 D 4 The interior of the pressure vessel must be inspected at least once a year If there is any presence of scale refer to Preventive Maintenance Water Treat ment above and consult a local water treatment firm immediately Scale for mation on the elements will cause heat ing element failures Scale formation elsewhere in the boiler can cause er ratic control operation particularly on water level controls 8 D 5 When the boiler is inspected rod out the pipes to the water column s in spect the operation of the floats in the level controller s 8 D 6 Remove and clean the low water cutoff probe 8 D 7 Steam Boiler Special Maintenance 8 D 7 a All LOCHINVAR steam boilers are supplied with a surface blow off connection If surface blow off valves are not Factory installed they should be installed in the field The surface blow off should be used as often as necessary to re move organics which accumulate at the water surface and to limit TDS Boiler water TDS should not exc
23. repair part will be provided under the conditions of the Limited War ranty If a replacement part has been pur chased from the Factory these goods will be invoiced and shipped under standard sales terms Once the defective goods are returned within the authorized 30 day time period and the Factory verifies that the material and or workmanship is defective then appropriate credit will be issued for the part or a repair will be made Return shipments must be freight prepaid Freight collect shipments will not be accepted me Page 21 Chapter 9 2 N
24. t or foreign materials have accu mulated there If there has been severe exposure to dust the contactors should be disas sembled and cleaned Dust in the contactors will cause contactor chat tering and eventual destruction of the contacts All components should be clean and free of dust moisture and foreign matter PRE STARTUP INSPECTION 4 C 6 Verify that field installed control and load connections have been prop erly installed 4 D HEATING ELEMENTS CAUTION Moisture in the elements may re sult in damage to the elements NOTE There is a possibility that during ship ment or storage prior to operation the ele ments may accumulate moisture The moisture will turn to steam when the elements are turned on and may rupture the element casing 4 D 1 How to check Elements for Moisture Take a reading with a megger between the contactor terminals load side to ground for each contactor Moisture is present if the reading is less than 1 megohm for standard 3 phase connection 4 D 2 Removal of Moisture in Element Method 1 Remove the fuses going to that contactor The fuses should be removed so that dur ing the first day of operation the affected element will not be energized allowing the hot boiler to drive the moisture out at a con trolled rate Chapter 4 2 Chapter 4 4 0 3 4 0 4 4 D 5 Removal of Moisture in Element Method 2 An alternate heating method
25. urned ON depress Chapter 5 2 STARTUP INSTRUCTION the alarm silence button Check the boiler to make certain that no limit conditions exist by noting if the alarm pilot light is illuminated The alarm will sound momentarily on some boilers when power is initially applied 5 B 5 b Boilers with Manual Reset Button s may require resetting of the manual reset switch upon initial application of power and after the interruption of power or the trip out of a limit control 5 B 6 Sequencing of Element Circuits 5 B 6 a On boilers with step controls the boiler will always start with no steps energized 5 B 6 b As the steps begin cycling on the pilot lights will light up one at a time indicating that power has been ap plied to the associated contactor Coils 5 B 6 c For electric boilers with ON OFF PREHEAT switches when the switch is down in the PRE HEAT position only part approxi mately 25 of the steps may be activated 5 B 6 d When the boiler outlet water tem perature or steam pressure is at or near setpoint turn the boiler ON OFF PREHEAT switch OFF then to ON again The controls will recycle to the no load condition The steps should then begin to cy cle on as needed and all of the steps may come on if necessary Page 12 Chapter 6 SEQUENCE OF OPERATION 6 A ACTIVATION OF HEATING ELEMENT CIRCUITS 6 A 1 Contactors The heating elements are energized by pi lot operation That
26. vered at all times while work is in progress 2 C 1 Care must be taken not to damage controls or deform the boiler sheet CAUTION Do not use the boiler housing top metal during removal of the crate 2 C 2 If using pry bars or fork lifts be certain for scaffolding to support the boiler weight by the skids or channel base Chapter 2 7 N Page 4 Chapter 2 STORAGE amp HANDLING Minimum Clearance Recommendations and General Dimensional Data for Boiler Placement Compac ren SIDE FRONT TOP ji LEFT END FRONT TOP Electric Steam Boiler tatere tenet Se Sos PRessune PRESSURE A com Ft sm saw sou auc CONTR gae met ie te ay gs za L ak m a LEFT END FRONT NOTE Consult local codes for specific requirements and refer to the Dimensional Drawing DD and Wiring Diagram WD provided with the unit Page 5 Chapter 2 2 Chapter 3 INSTALLATION 3 A PIPING CONNECTIONS NOTE Some of the following piping may have been completed at the Factory 3 A 1 Boiler piping connections and valves MUST comply with state and local cod s in addition to compliance with ANSI piping requirements CAUTION The pipe extensions outside the boiler are usually the extensions of pipes which are permanently welded into the boi
27. ves the right to vary any details in this manual without notice TABLE OF CONTENTS RRS a E CHAPTER 1 INTRODUCTION A General Information B Local Regulations C Recommendations 1 Preventive Maintenance 2 Water Treatment CHAPTER 2 STORAGE amp HANDLING A Receiving B Storage C Uncrating D PlacemenT Figure 1 1 Minimum Clearance CHAPTER 3 INSTALLATION A Piping Connections B Electrical Connections 1 Power Feed Wiring 2 Grounding Conductors 3 Control Wiring C Filling the System CHAPTER 4 PRE STARTUP INSPECTION A Minimum Equipment for Startup B Mechanical System Checks 1 Plumbing Connections 2 Feedpump Circ Pumps 3 System Flush 4 Valves C Electrical System Checks D Heating Elements E Inspection Power Voltage CHAPTER 5 STARTUP INSTRUCTIONS A Control Settings 1 Controller 2 High Limit 3 Low Water Cutoffs 4 Low Limit Sensors B Operating Instructions CHAPTER 6 SEQUENCE OF OPERATION A Activation of Heating Element Circuits 1 Contactors 2 Fuses B Sequencing Controls 1 Staged Control Circuit 2 Proportional Step Controls 3 Recycle Feature 4 Preheat Switch CHAPTER 7 OPERATIONAL TESTING A Standard Controls 1 135 ohm Controllers 2 Solid State Controls B Outdoor Reset Controls 1 135 ohm Controllers 2 Solid State Dual Input Controls CHAPTER 8 PREVENTIVE MAINTENANCE A General B Water Treatment Figure 8 1 Feedwater Boiler Water Properties C Electrical System Maintenance
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