HP25 SERIES UNITS
Contents
1. CHARGE COMPENSATOR OPERATION S COOLING MODE Vapor Line ae To Outdoor Coil Compensator Tank Liquid Is Forced Into Circulation During cooling mode the va por line is hotter than the liquid line Stored liquid is heated and forced into circulation Stored Liquid Out To Liquid Line To Be Circulated Through Indoor coil Vapor Line From Compressor Discharge Port Vapor Line From Outdoor Coil HEATING MODE Compensator Tank Fills With Liquid During heating mode the vapor line is cooler than the liquid line Excess vapor from the indoor coil non condensed vapor is forced into the charge compensator where it condenses and collects Excess Vapor In From Outdoor Coil To Be Condensed and Stored vy In Compensator as Liquid Vapor Line To Compressor Suction Port FIGURE 17 11 1 Factory Charge Fitting FACTORY PROCESS PORT LIQUID LINE ASSEMBLY PROCESS NY PORT F SEAL HP25 units are equipped a liquid charging port fig ure 18 used exclusively for factory charging the unit This port is located in the liquid line as shown and is not field serviceable The port is equipped with an in ternal valve the cap seal can be removed without re frigerant loss However the cap seal should be se cured in order to ensure a leak free seal V CHARGING Unit charge is based on a matching indoo2. SERVICE INFORMATION 25 LENNOX industries Inc Corp 9326 13 Litho U S A HP25 SERIES UNITS The HP25 is a high efficiency residential split system heat pump which features a scroll compressor It op erates much like a standard heat pump but the HP25 s scroll compressor is unique in the way that it com presses refrigerant Several models are available in sizes ranging from 1 1 2 through 5 tons The series uses expansion valves in the outdoor unit and in the indoor unit This manual is divided into sections which discuss the major components refrigerant system and charging procedures maintenance and operation sequences All specifications in this manual are subject to change SCROLL COMPRESSOR I APPLICATION All major components indoor blower coils must be matched according to Lennox recommendations for the compressor to be covered under warranty Refer to the Engineering Handbook for approved system matchups A misapplied system will cause erratic op eration and can result in early compressor failure ll SCROLL COMPRESSOR The scroll compressor design is simple efficient and requires few moving parts A cutaway diagram of the scroll compressor is shown at left The scrolls are lo cated in the top of the compressor can and the motoris located in the bottom of
3. WARNING ELECTRIC SHOCK HAZARD CAN CAUSE BE GROUNDED I INJURY OR DEATH UNIT MUST WITH NATIONAL AND LOCAL CODES LENNOX Larie ne WIRING DIAGRAM HEAT PUMP OUTDOOR UNITS HP25 211 261 1 P HP25 311 411 461 1 P HP25 511 651 1 P ____HEAT PUMP SECTION 5 1905 Lennox Indvetrice Ine B Operation Sequence Low Voltage 1 Transformer in indoor unit supplies 24VAC power to the thermostat and outdoor unit controls 2 Cooling demand energizes thermostat terminals and O Voltage from terminal Y passes through high pressure switch and energizes compressor contactor 3 Thermostat demand from thermostat terminal Y is also supplied to the defrost control Defrost con trol cannot operate in cooling mode because de frost thermostat cannot close 4 Thermostat demand from thermostat terminal O energizes reversing valve 5 Heating demand energizes thermostat terminal Y Voltage from terminal Y passes through high pres sure switch and energizes compressor contactor 529 639 Lithe U S A 6 During heating operation when outdoor coil drops below 35 4 F the defrost thermostat closes When defrost thermostat closes defrost timer begins timing If defrost thermostat remains closed at the end of 30 60 or 90 minutes defrost relay energizes and defrost begins 7 When defrost relay energizes reversing valve and indoor electric heat relay are energized 8 Defrost continues until 14 1 minutes have
4. SUBCOOLING METHOD EXPANSION VALVE SYSTEMS AMBIEN MP HP25 211 HP25 261 HP25 311 25 411 25 461 25 511 25 651 Add refrigerant to make the liquid line cooler Recover refrigerant to make the liquid line warmer 6 When unit is properly charged liquid line pressures should approximate those given in table 8 Page 13 8 VORMA OPER OUTDOOR COIL AIR ENTERING TEMPERA LIQ SUC 10 5 LIQ ATIN SUC 10 5 UR LIQ SUC LIQ SUC LIQ SUC LIQ SUC 10 5 10 5 10 5 10 5 PSIG PSIG PSIG SUC 10 5 PSIG PSIG m 78 138 o 91 4 2n 6 64 230 66 224 56 250 A IMPORTANT Use table 8 as a general guide for performing maintenance checks Table 8 is not a procedure for charging the system Minor variations in pressures may be expected due to differences in installations Significant deviations may mean the system is not properly charged or that a problem exists with some component in the system Used prudently table 8 could serve as a useful service guide D Oil Charge Refer to table 1 on page 3 VI MAINTENANCE At the beginning of each heating or cooling season the system should be cleaned as follows A Outdoor Unit 1 Clean and inspect outdoor coil Coil may be flushed with a water hose 2 Visually inspect all connecting lines joints and coils for evidence of oi
5. 2 HP25 DUAL CAPACITOR RATING Terminal MFD 25 211 25 261 25 311 25 411 461 25 411 461 i HP25 511 orem oT HP25 651 L Defrost Thermostat A defrost thermostat is mounted on the liquid line be tween the filter drier and the distributor The thermo stat opens at 70 5 F and closes at 35 5 F For defrost to begin the defrost thermostat must be closed when the defrost timer calls for defrost M Defrost Relay The defrost relay controls defrost The relay is a 3PDT relay powered 24 VAC from the thermostat and is en abled during both cooling and heating modes except emergency heat It is only powered when the defrost control is calling for defrost When energized the re versing valve and indoor auxiliary heat are energized Simultaneously the outdoor fan is de energized The defrost relay latches in for the duration of the defrost period Refer to unit wiring diagram and operation se quence in the back of this manual N Reversing Valve and Solenoid A refrigerant reversing valve with electromechanical solenoid is used to reverse refrigerant flow during unit operation The reversing valve is energized during cooling demand and during defrost Refer to figures 12 and 13 for more information O Defrost Timer The CMC1 defrost control figure 8 is solid state control manufactured by Hamilton Standard The control pro vides automatic switching from normal heating o
6. Type Service Valve A ball type full service valve is used on HP25 651 units This valve is manufactured by Aeroquip All vapor line service valves function the same way differences are in construction Valves not rebuildable If a valve has failed it must be replaced A ball valve valve is illus trated in figure 16 The ball valve is equipped with a service port A schrader valve is factory installed Aservice port cap is supplied to protect the schrader valve from con tamination and assure a leak free seal Compensator All HP25 units are equipped with a charge compensa tor in addition to the factory installed accumulator See figure 17 The purpose of the charge compensator is to optimize system heating performance by automatical ly removing and storing excess refrigerant during the heating cycle During the cooling cycle the refrigerant is automatically returned to circulation VAPOR LINE BALL TYPE SERVICE VALVE VALVE OPEN USE ADJUSTABLE WRENCH ROTATE STEM CLOCKWISE 90 TO CLOSE ROTATE STEM COUNTER CLOCKWISE 90 TO CLOSE STEM CAP INLET FROM INDOOR COIL CAP SERVICE PORT SCHRADER VALVE FIGURE 16 D Accumulator HP25 511 and 651 units are equipped with an accumu lator in addition to the factory installed charge compen sator See figure 17 The purpose of the accumulator is to trap and evaporate all liquid refrigerant and prevent liquid refrigerant from entering the compressor
7. connections Use Lennox L10 series line sets as shown in table 4 or field fabricated refrigerant lines Refer to the piping section of the Lennox Service Unit Information Manual SUI 803 L9 for proper size type and application of field fabricated lines TABLE 4 VAPOR L10 Model No LINE LINE SETS L10 26 25 211 20 tt 50 ft 25 261 110 41 25 311 25 411 20 ft 50 ft HP25 461 HP25 511 25 651 check valve and expansion valve are used in parallel in the liquid line The check valve is closed when the unit is in heating mode to force refrigerant through the expansion valve The check valve is open when the unit is in cooling mode Separate discharge and vapor service ports are pro vided at the compressor for connection of gauge man ifold during charging procedure Figures 12 and 13 show HP25 gauge manifold connections B Service Valves The liquid line and vapor line service valves and gauge ports are accessible from outside of the unit Full ser vice liquid and vapor line valves are used See figures 14 and 15 The service ports are used for leak testing evacuating charging and checking charge 1 Liquid Line Service Valve A full service liquid line valve made by one of several manufacturers may be used All liquid line service valves function the same way differences are in construction Valves manufactured by Parker are forged assemblies Valves manufactured by Primore are brazed to
8. elapsed or until the defrost thermostat opens When defrost thermostat opens to terminate de frost the defrost timer loses power and resets De frost timing is stopped until the next call for defrost when defrost thermostat closes 9 After each thermostat demand time delay locks out the circuit to conpressor contactor coil and de frost control for 5 2 minutes At the end of the timed period the time delay allows the compres sor contactor and defrost control to be energized upon demand as in step 2 Page 16 LINE VOLTAGE OPERATION SEQUENCE B4 LEADLESS MOTOR B4 ON 211 261 AND 5 1 SERIES ONLY C Operation Sequence Line Voltage 4 During defrost defrost relay contacts 4 5 open to de energize the outdoor fan 1 Compressor contactor is energized by indoor ther mostat demand Contactor contacts close when contactor is energized A WARNING 2 When the contactor closes the outdoor fan im 25 UNITS USING SINGLE POLE CONTACTORS mediately begins operating and the compressor ONE LEG OF COMPRESSOR CAPACITOR AND begins startub CONDENSER FAN ARE CONNECTED LINE 3 Compressor terminal C is energized by L1 through VOLTAGE AT ALL TIMES POTENTIAL EXISTS FOR the contactor contacts Terminal R is powered by ELECTRICAL SHOCK RESULTING IN INJURY OR L2 through the contactor powered at all times DEATH REMOVE ALL POWER AT DISCONNECT Terminal S is powered by the start capacitor and i BEFORE SERV
9. orebsize amps _ iT o o Minimum circuit ampacity es ss so ze Refer to National Electrical Code Manual to determine wire fuse and disconnect size requirements NOTE Extremes of operating range are plus 10 and minus 5 of line voltage SPECIFICATIONS Face area sq ft ee a a o o a TNo ofBlades O Condenser gt 50 460 was 20 22 charge furnished 1265 802 18 231 Vapor line connection tz ELECTRICAL DATA PAST 551 HP25 651 O Line voltage data 60hz 1 phase 28297 _ TS Oe E E Compressor w oa Locked rotor amps 17 18 19 e Condenser Fullloadamps So O Fan Motor Locked rotor amps 20 o gt SSS Max fuse orb _ Minimum circuitampacity 0 312 384 Refer to National Electrical Code Manual to determine wire fuse and disconnect size requirements NOTE Extremes of operating range are plus 10 and minus 5 of line voltage Page 2 SCROLL FORM FIGURE 1 CROSS SECTION OF SCROLLS DISCHARGE STATIONARY SCROLL 22 SMA SW a A 2222 7 7 77 2722 SASASSASSASSY SAANAAASAASSY MAAAAAASSAS 77777772 SSS 2 2 72 OR
10. the compressor can The oil level is immediately below the motor The scroll is a simple compression concept centered around the unique spiral shape of the scroll and its in herent properties Figure 1 shows the basic scroll form Two identical scrolls are mated together forming con centric spiral shapes figure 2 One scroll remains sta tionary while the other is allowed to orbit figure 3 Note that the orbiting scroll does not rotate or turn but merely orbits the stationary scroll 1 1993 Lennox Industries Inc 9 ature SPECIFICATIONS Face area sq ft 10 40 11 83 8 57 11 83 15 34 15 94 15 34 15 94 Tube diameter in 1 2 of Rows Fins per inch Diameter in 9099 y a y a No ofBlades 4 4 3 3 Condenser Motorno vo vo 6 16 4 cfm 85 6 1 asso 350 Rem 1 5 B00 Watts 1 0 0 20 20 HCFC 22 charge furnished 7Ibs ooz 8 202 1054044 01402 8 vo sees 3 8 Vapor line connection 58 34 34 ELECTRICAL DATA _Model No HP25 211 5 61 531 25 41 Line voltage data 60hz 1 phase 208 230V 208 230V 208 230V 208 230V Rated 97 mse ss Compressor o _ Ftocked rotor amps soo mo os Condenser Funioaaames 11 11 11 114 Fan Motor Locked rotor amps 20 2 gt _ Max fuse
11. AND MAXIMUM EERS FACTORY WIRING VALID FOR GE rma l 111 ONEYWELL INDOOR THERMO 208 230 60 1 eee eed STAT IF WHITE RODGERS IN oe ee ee ee eek DOOR THERMOSTAT IS USED DIS Se CONNECT WIRE FROM COMMON oo AND RECONNECT Y TERMINAL GROUND OUTDOOR UNIT LOW VOLTAGE TERMINALS USE COPPER CONDUCTOR ONLY YELLOW OUTDOOR THERMOSTAT RELAY IF USED INDOOR UNIT JUNCTION BOX EXTRA LOW VOLTAGE FACTORY INSTALLED a ee ee ee LINE VOLTAGE FACTORY INSTALLED Bear Sn T nee 11 EXTRA LOW VOLTAGE FIELD INSTALLED am LINE VOLTAGE FIELD INSTALLED Page 15 LOW VOLTAGE OPERATION SEQUENCE FOR 621 LINE VOLTAGE FIELD INSTALLED CLASS II VOLTAGE FIELD INSTALLED DENOTES OPTIONAL COMPONENTS FOR USE WITH COPPER CONDUCTORS ONLY REFER TO UNIT RATING PLATE FOR MINIMUM i 3 511 4 651 UNITS HOOKUP WITH WHITE RODGERS OR HEATCRAFT ELECTRONIC THERMOSTAT CIRCUIT AMPACITY AND MAXIMUM FUSE SIZE 4564 4 RT3 HOOKUP WITH GE OR HONEYWELL THERMOSTAT ONLY IF THERMOSTAT IS NOT INTERNAL A USED ON 651 SERIES UNITS ONLY
12. BITING SCROLL 55 Y TIPS SEALED BY DISCHARGE PRESSURE FIGURE 2 NOTE The head of a scroll compressor may be hot since it is in constant contact with discharge gas The counterclockwise orbiting scroll draws gas into the outer crescent shaped gas pocket created by the two scrolls figure 3 1 The centrifugal action of the orbiting scroll seals off the flanks of the scrolls fig ure 3 2 Asthe orbiting motion continues the gasis forced toward the center of the scroll and the gas pocket becomes compressed figure 3 3 When the compressed gas reaches the center it is discharged vertically into a chamber and discharge port in the top of the compressor figure 2 The discharge pres sure forcing down on the top scroll helps seal off the upper and lower edges tips of the scrolls figure 2 During asingle orbit several pockets of gas are com pressed simultaneously providing smooth continu ous compression The scroll compressor is tolerant to the effects of liquid return If liquid enters the scrolls the orbiting scroll is allowed to separate from the stationary scroll The liq uid is worked toward the center of the scroll and is dis charged If the compressor is replaced conventional Lennox cleanup practices must be used HOW A SCROLL WORKS 5 Sea A POCKET 1 STATIONARY SCROLL e MOVEMENT OF ORBIT _ FLANKS amp MOVEMENT OF ORBIT SEALED BY PRESSURE GAS INTERME
13. DIATE PRESSURE we GAS CRESCENT SHAPED GAS POCKET SUCTION ORBITING SCROLL 2 SUCTION CENTRIFUGAL FORCE 4 DISCHARGE POCKET FIGURE 3 Page 3 COMPONENTS A Transformer The contactor reversing valve time delay tempera ture sensor and defrost timer are all powered by 24VAC supplied by the indoor unit All other controls in the outdoor unit are powered by line voltage Refer to unit wiring diagram The HP25 is not equipped with an in ternal line voltage to 24V transformer B Contactor The compressor is energized by a contactor located in the control box All units except HP25 651 use SPST contactors HP25 651 uses a DPST contactor The con tactor is energized by indoor thermostat terminal Y when thermostat demand is present WARNING HP25 UNITS USING SINGLE POLE CONTACTORS ONE LEG OF COMPRESSOR CAPACITOR AND CONDENSER FAN ARE CONNECTED TO LINE VOLTAGE AT ALL TIMES POTENTIAL EXISTS FOR ELECTRICAL SHOCK RESULTING IN INJURY OR DEATH REMOVE ALL POWER AT DISCON NECT BEFORE SERVICING HP25 UNIT COMPONENTS DUAL CAPACITOR THERMOMETER WELL EXPANSION VALVE DISTRIBUTOR DEFROST THERMOSTAT FILTER DRIER WITH INTERNAL CHECK VALVE FACTORY CHARGE C TD1 1 Time Delay Each HP25 is equipped with a Lennox built 1 1 time delay located in the control box figure 4 The time delay is electrically connected between thermostat terminal Y1 and the compressor contactor On initial
14. EAT PUMP OUTDOOR UNITS HP25 211 261 1 P 84 HP25 311 411 461 1 P LEADLESS MOTOR B4 HP25 51 1 651 1 P 208 230 60 ON 211 261 AND 1993 Lennox Industries Inc Litho U S A Page 18 PLACE TEMPERATURE CONTROL DIAGRAM HERE
15. ICING the H side of the dual capacitor Page 17 D Complete Diagram lt a 2 x p a a 24V POWER up FOR 621 Ds FOR 621V B CB CBH2 DESCRIPTION EY COMPONENT COMPRESSOR MOTOR OUTDOOR FAN CAPACI TOR DUAL CONTROL DEFROST DELAY COMPRESSOR OR CONTACTOR COMPRESSOR K4 1 2 5 RELAY DEFROST _ _ _ 26 RELAY EMERGENCY HEAT 58 1 1 AMB KIT a LI SENSOR AMBIENT COMPENSATION iS4 7 PRESSURE SWITCH iso TEMPERATURE S6 7 lt 0 5 525 THERMOSTAT LO_AMB CUT IN a 24 ss SWI TCH LOSS OF CHARGE 554 7 LIGHT 4 TERMINAL STRIP LOW VOLTAGE TNE VOLTAGE FIELD INSTALLED CLASS II VOLTAGE FIELD INSTALLED DENOTES OPTIONAL COMPONENTS IS A FIELD INSTALLED OPTION CONDUCTORS ONLY ON 511 amp 651 UNITS REFER TO UNIT RATING At HOOKUP WITH WHITE RODGERS OR PLATE FOR MINIMUM HEATCRAFT ELECTRONIC THERMOSTAT CIRCUIT AMPACITY AND MAXIMUM FUSE SIZE A S54 amp RT3 HOOKUP WITH THERMOSTAT IS NOT INTERNAL A USED ON 651 SERIES UNITS ONLY WARNING ELECTRIC SHOCK HAZARD CAN CAUSE INJURY OR DEATH UNIT MUST BE GROUNDED ACCORDANCE WITH NATIONAL AND LOCAL CODES LENNOX WIRING DIAGRAM 1 95 H
16. METHOD EXPANSION VALVE SYSTEMS AMBIENT TEMPERATURE OF 60 F 16 C OR ABOVE Liquid Line F Warmer Than Outside Ambient Temperature HP25 211 8 HP25 261 2531 8 5 7 8 25461 8 2551 65 5 61 5 SUBCOOLING METHOD SYSTEMS Ambient Temperature Below 60 F 16 C NOTE It may be necessary to restrict air flow in order to reach liquid pressures in the 200 250 psig range which are required for checking charge Block equal sections of air intake panels as shown in figure 19 moving obstruc tions sideways until liquid pressures in the 200 250 psig range are reached BLOCKING OUTDOOR COIL Block outdoor coil one side at a time with cardboard or plastic sheets until proper testing pressures are reached FIGURE 19 1 Connect gauge manifold Connect an upright HCFC 22 drum to center port of gauge manifold 2 Operate indoor and outdoor units in cooling mode Allow units to run until system pressures stabilize 3 Make sure thermometer well is filled with mineral oil before checking liquid line temperature 4 Read liquid line pressure and convert to condensing temperature using temperature pressure conver sion chart Condensing temperature from gauges should be a few degrees warmer than the liquid line 5 Place thermometer in well and read liquid line tem perature Table 7 shows how much warmer the con densing temperature should be TABLE 7
17. NING COMPRESSOR MUST BE GROUNDED DO NOT OPERATE WITHOUT PROTECTIVE COVER OVER TERMINALS DISCONNECT ALL POWER BEFORE REMOVING PROTECTIVE COVER DISCHARGE CAPACITORS BEFORE SERVICING UNIT COMPRESSOR WIRING DIAGRAM IS FURNISHED INSIDE COMPRESSOR TERMINAL BOX COVER FAILURE TO FOLLOW THESE PRECAUTIONS COULD CAUSE ELECTRICAL SHOCK RESULTING IN INJURY OR DEATH FIGURE 5 The sensor can be accessed by prying off the snap plug on top of the compressor see figure 6 Make sure to securely reseal the sensor after replacement The sen sor pigtails are located inside the unit control box Fig ure 5 shows the arrangement of compressor line volt age terminals and discharge sensor pigtails SCROLL HIGH TEMPERATURE LIMIT CHANGEOUT ro PLASTIC CAP SEALANT BLUE l PRONG THERMAL GREASE WHITE 2222 N U W GROMMET COMPRESSOR Instructions 1 With power off disconnect wiring to limit 2 Dislodge limit cap assembly from compressor Plastic cap and sili cone seal will break away Discard all pieces 3 Remove thermostat and grommet from compressor Thoroughly clean all blue adhesive and white silicone thermal grease from com pressor and the inside the thermostat tube Thermostat tube should be clean and free of debris 4 Using Lennox kit 93G8601 dip end of thermostat into plastic bottle la beled Silicone Thermal Grease G641 and coat end of thermo stat Carefully
18. OTE below NOTE Control will not go into test mode when disconnected from unit Unit load must be applied to control terminals before the control will go into test mode However if outdoor ambient is 40 F or warmer the defrost thermostat may not close and may not allow test mode to initiate If this happens it may be neces sary to jumper 24V to the 24V terminal in order to initiate defrost 3 Connect jumper TST pins as shown 4 Turn indoor thermostat to heat mode and adjust to highest temperature setting 5 Turn on power to unit 6 See Table 3 for control timings in TST mode 7 Be sure to turn off power and remove jumper when test is com plete Turn on power and thermostat FIGURE 11 A IMPORTANT Control will begin test mode only if normal load is applied to control terminals Do not attempt to operate or test control out of unit 6 COM Terminal Terminal COM provides 24VAC Common 7 OUT Terminal Terminal OUT controls defrost when connected to one side of the defrost relay coil An internal relay connected to terminal OUT closes to allow external defrost relay to energize and initiate de frost At the end of the defrost period the internal relay connected to terminal OUT opens to de energize the external defrost relay IV REFRIGERANT SYSTEM A Plumbing Field refrigerant piping consists of liquid and vapor lines from the outdoor unit sweat
19. R LINE SERVICE VALVE VALVE CLOSED KNIFE EDGE SEAL STEM INLET CAP FROM INDOOR COIL INSERT HEX WRENCH HERE PART 49A71 AND SERVICE WRENCH SERVICE PORT SCHRADER VALVE OPEN TO LINE SET WHEN VALVE IS CLOSED FRONT SEATED VALVE FRONT SEATED OUTLET TO COMPRESSOR FIGURE 15 To Access Schrader Port 1 Remove service port cap with an adjustable wrench 2 Connect gauge to the service port 3 When testing is completed replace service port cap Tighten finger tight then tighten an addi tional 1 6 turn To Open Vapor Line Service Valve 1 Remove stem cap with an adjustable wrench 2 Using service wrench 5 16 hex head extension part 49A71 back the stem out counterclockwise until the valve stem just touches the retaining ring DANGER Do not attempt to backseat this valve Attempts to backseat this valve will cause snap ring to explode from valve body under pressure of refrigerant Personal injury and unit damage will result 3 Replace stem cap tighten firmly Tighten finger tight then tighten an additional 1 6 turn Page 10 Close Vapor Line Service Valve 1 Remove stem cap with an adjustable wrench 2 Using service wrench and 5 16 hex head exten sion part 49A71 turn stem in clockwise to seat the valve Tighten firmly 3 Replace stem cap Tighten finger tight then tight en an additional 1 6 turn 3 Vapor Line Ball
20. SE SERVICE WRENCH PART 18P66 54B64 or 12P95 STEM CAP A IMPORTANT A schrader valve is not provided on the liquid line service port Valve must be backseated to turn off pressure to service port FIGURE 14 A CAUTION The service port cap is used to seal the liquid line service valve Access to service port requires backseating the service valve to isolate the service port from the system Failure to do so will cause refrigerant leakage 3 Replace stem cap finger tighten then tighten additional 1 6 turn 2 Vapor Line Service Valve A full service non backseating vapor line service valve is used on all HP25 series units Different manufacturers of valves may be used All vapor line service valves function the same way differences are in construction Valves manufactured by Parker are forged assem blies Primore and Aeroquip valves are brazed to gether Valves are not rebuildable If a valve has failed it must be replaced The vapor line service valve is illustrated in figure 15 The valve is equipped with a service port Aschrader valve is factory installed A service port cap is sup plied to protect the schrader valve from contamina tion and assure a leak free seal VAPOR LINE SERVICE VALVE VALVE OPEN INSERT HEX WRENCH SNAP RING HERE PART 49A71 AND KNIFE EDGE SERVICE WRENCH INLET FROM INDOOR COIL STEM CAP SERVICE CAP SCHRADER VALVE SERVICE PORT VAPO
21. elease nitrogen pres sure from system 6 Reconnect vacuum pump to manifold center port hose Evacuate the system to an absolute pressure less than 197 inches of mercury 5mm of mercury or 5000 microns then turn off vacuum pump If the absolute pressure rises above 197 inches of mer cury 5 mm of mercury or 5000 microns within a Page 12 20 minute period after stopping vacuum pump repeat step 6 If not evacuation is complete This evacuation procedure is adequate for a new installation with clean and dry lines If excessive moisture is present the evacuation process may be required more than once 7 After evacuation has been completed close gauge manifold service valves Disconnect vacuum pump from manifold center port and connect re frigerant drum Pressurize system slightly with re frigerant to break vacuum C Charging Charging must be done in the cooling mode If system is completely void of refrigerant the recommended and most accurate method of charging is to weigh the re frigerant into the unit according to the total amount shown on the unit nameplate If weighing facilities are not available or if unit is just low on charge the following procedure applies Separate discharge and vapor line service ports are provided outside the unit for connection of gauge manifold during charging procedure as well as a suc tion line service port The following procedures are intended as a general guide for use with expansi
22. gether Valves are not rebuildable If a valve has failed it must be replaced The liquid line ser vice valve is illustrated in figure 14 L10 65 20 ft 50 ft Field Fabricate Page 8 25 COOLING CYCLE SHOWING GAUGE MANIFOLD CONNECTIONS DEFROST THERMOSTAT i EXPANSION VALVE OUTDOOR UNIT OUTDOOR CHARGE COIL COMPENSATOR NOTE ARROWS INDICATE DIRECTION OF REVERSING REFRIGERANT FLOW FILTER DRIER WITH INTERNAL CHECK VALVE STRAINER INTERNAL COMPRESSOR HIGH PRESSURE LIMIT SERVICE INDOOR UNIT SUCTION p HIGH SUCTION PRESSURE LINE SERVICE COMPRESSOR LIQUID BOGE gt THERMOMETER WELL 27 GATOR Sell FIGURE 12 HP25 HEATING CYCLE SHOWING GAUGE MANIFOLD CONNECTIONS DEFROST THERMOSTAT EXPANSION VAINE CHARGE REVERSING OUTDOOR COMPENSATOR VALVE FILTER DRIER COIL WITH INTERNAL CHECK VALVE STRAINER _ INTERNAL HIGH PRESSURE COMPRESSOR LIMIT 54 a O 714 OUTDOOR UNIT NOTE ARROWS INDICATE DIRECTION OF REFRIGERANT FLOW INDOOR UNIT HIGH SUCTION PRESSURE SUCTION SERVICE PORT LIQUID LINE SERVICE PORT COMPRESSOR INDOOR EXPANSION Colt VALVE OR FIGURE 13 The valve is equipped with a service port There is no 5 Replace service port and stem cap Tighten finger schrader valve installed in the liquid line serv
23. ice port A service port cap is supplied to seal off the port The liquid line service valve is a front and back seating valve When the valve is backseated the service port is not pressurized The service port cap can be removed and gauge connections can be made To Access Service Port 1 Remove the stem cap Use a service wrench part 18P66 54B64 or 12P95 to make sure the ser vice valve is backseated 2 Remove service port and connect high pressure gauge to service port 3 Using service wrench open valve stem one turn clockwise from backseated position 4 When finished using port backseat stem with ser vice wrench Tighten firmly tight then tighten an additional 1 6 turn To Close Off Service Port 1 Using service wrench backseat valve Turn stem counterclockwise b Tighten firmly To Open Liquid Line Service Valve 1 Remove the stem cap with an adjustable wrench 2 Using service wrench backseat valve Turn stem counterclockwise until backseated b Tighten firmly 3 Replace stem cap finger tighten then tighten additional 1 6 turn To Close Liquid Line Service Valve 1 Remove the stem cap with an adjustable wrench 2 Turnthe stem inclockwise with service wrench to front seat the valve Tighten firmly Page 9 TO LINE SERVICE PORT CAP SERVICE PORT OPEN TO KNIFE EDGE SEAL LINE SET WHEN FRONT SEATED AND CLOSED OFF WHEN BACK SEATED VALVE STEM U
24. igerant to produce substances that corrode copper piping and compressor parts 1 Attach gauge manifold and connect vacuum pump with vacuum gauge to center port of gauge manifold With both gauge manifold ser vice valves open start pump and evacuate evapo rator and refrigerant lines A IMPORTANT A temperature vacuum gauge mercury vacuum U tube thermocouple gauge should used The usual Bourdon tube gauges are not accurate enough in the vacuum range A IMPORTANT The compressor should never be used to evacuate refrigeration air conditioning system CAUTION Danger of Equipment Damage Avoid deep vacu um operation Do not use compressors to evacuate a system Extremely low vacuums can cause inter nal arcing and compressor failure Damage caused by deep vacuum operation will void warranty 2 Evacuate the system to an absolute pressure of 92 inches of mercury 23 mm of mercury or 23 000 microns 3 After system has been evacuated to an absolute pressure of 92 iches of mercury 23 mm of mercu ry or 23 000 microns close manifold valve to center port 4 Stop vacuum pump and disconnect from gauge manifold Attach a drum of dry nitrogen to center port of gauge manifold open drum valve slightly to purge line then break vacuum in system to 3 psig 20 7 kPa pressure by opening manifold high pressure valve to center port 5 Close nitrogen drum valve disconnect drum from manifold center port and r
25. inal Strip All HP25s are equipped with a low voltage terminal strip located in the unit control box for making thermo stat wiring connections refer to figure 4 Table 1 shows the specifications of compressors used in HP25 series units TABLE 1 Unit 25 411 25 461 25 511 25 651 Shipped with conventional white Sontex 200LT 365 may be used if additional oil is required F High Pressure Switch A manual reset single pole single throw high pressure switch located in the discharge line of the compressor shuts off the compressor when discharge pressure rises above the factory setting The switch is normally closed and is permanently adjusted to trip open at 410 10 psi See figure 4 for reset switch location G Temperature Sensor Scroll compressors in HP25 211 through 461 units are equipped with a temperature sensor located on the outside top of the compressor The sensor is a SPST thermostat which opens when the discharge tempera ture exceeds 280 F 8 F on a temperature rise When the switch opens the circuit to the compressor contac tor and the time delay is de energized and the unit shuts off The switch automatically resets when the compressor temperature drops below 130 F 14 F COMPRESSOR TERMINAL BOX DISCHARGE TEMPERATURE SENSOR WIRES TO CONTROL BOX TO COMP TERM BOX IN 211 THROUGH 461 UNITS WAR
26. insert thermostat grommet assembly into thermostat tube of compressor Avoid contact with top of compressor 5 Clean excess thermal grease from under cap lip and top lip of com pressor opening 6 Install protector assembly as shown feeding wire leads through channel provided in cap 7 Apply a bead of sealant around lip of cap at area shown in illustration and into the thermostat tube area 8 Install assembly as shown Align wires to channel in compressor shell Sufficient force is required to snap plastic cap into tube to en gage all three prongs 9 Re connect wiring 10 After completing thermostat replacement discard remaining parts FIGURE 6 Page 5 H Service Light Thermostat All units are equipped with a service light thermostat located on the compressor discharge line The switch is electrically connected to the service light in the in door thermostat The switch is closed on compressor startup and the thermostat service light is momentari ly lighted When compressor discharge line tempera ture reaches 130 5 F the thermostat opens and the service light goes off If discharge line temperature drops below 110 5 F during unit operation indicating a problem in the sys tem the thermostat closes and the service light is powered to indicate service is needed Fan Motor The specifications table on page 2 of this manual shows the specifications of outdoor fans used in HP25s In al
27. ircuit board pin W1 Table 3 shows the timings of each pin The defrost interval can be field changed to 30 60 or 90 minutes The defrost period 14 min utes cannot be changed To change the interval be tween defrosts simply remove the jumper from the pin it is connected to and reconnect the jumper to one of the other available pins see figure 10 TABLE 3 CMC1 DEFROST INTERVAL BETWEEN DEFROSTS CONTROL WITH UME CONNECTED TO DEFROST TIMINGS TIME NORMAL 30 3 90 9 14 14 OPERATION MIN MIN MIN MIN 7 0 7 14414 21 2 1 3 3 0 3 HLD Terminal Terminal HLD holds the internal timer in place between thermostat demands and allows the unit to continue timing upon resumption of thermostat demand Terminal HLD is connected directly to thermostat demand NOTE Hold function operates between thermostat demands only when defrost thermostat is closed This is the only time that the timer is operating 3 24V Terminal Terminal 24V receives 24VAC from the control transformer through the defrost thermostat This terminal powers the control s internal timer and re lays Terminal 24V is powered only when there is a call for defrost defrost thermostat closed The timer begins timing at 0 only after terminal 24V receives power HP25 SERIES UNITS TYPICAL DEFROST TIMINGS CLOSED 7 Note Cont
28. l leaks Page 14 PSIG 76 80 PSIG PSIG PSIG PSIG PSIG PSIG PSIG PSIG ms s 79 40 4 75 3 A IMPORTANT If insufficient heating or cooling occurs the unit should be gauged and refrigerant charge checked B Indoor Coil 1 Clean coil if necessary 2 Check lines and coil for evidence of oil leaks 3 Check condensate line and clean if necessary C Indoor Unit 1 Clean or change filters 2 Adjust blower cooling speed Static pressure drop over coil should be checked to determine correct blower CFM Refer to Lennox Engineer ing Handbook 3 Belt Drive Blowers Check condition and tension 4 Check all wiring for loose connections 5 Check for correct voltage at unit 6 Check amp draw on blower motor Unit nameplate Actual 7 VIL WIRING DIAGRAM OPERATING SEQUENCE A Field Wiring HP25 and BLOWER UNIT THERMOSTAT CONNECTIONS WITH OR WITHOUT AUXILIARY HEAT Some connections may not apply Refer to specific thermostat and indoor unit Indoor Thermostat HP25 Blower Unit AMBIENT SENSOR SERVICE LIGHT REVERSING VALVE COMPRESSOR EMERGENCY HEAT COMMON COMMON 2ND STAGE AUX HEAT POWER POWER 1ST STAGE AUX HEAT DEFROST SENSING 0000 INDOOR BLOWER FIELD WIRING THERMOSTAT REFER TO UNIT RATING PLATE FOR MUM CIRCUIT AMPACITY
29. l units the outdoor fan is controlled by the compressor contactor and is de energized when the defrost relay is energized J Ambient Compensating Thermistor All HP25s have an ambient compensating thermistor mounted on the outdoor fan wiring harness The therm istor isan NTC thermistor negative temperature coeffi cient increase in temperature equals decrease in re sistance see figure 7 The device is connected in se ries with the heat anticipation resistor inside the indoor thermostat This feature helps to prevent abnormal droop caused by the anticipation resistors As outdoor temperature increases the resistance across the therm istor drops As the resistance across the thermistor drops the current through the heat anticipation resistor increases Therefore heat anticipation increases as out door temperature decreases Resistance at 77 F 260 ohms 5 at 100 F 150 ohms at 32 F 861 ohms AMBIENT COMPENSATING THERMISTOR OUTDOOR FAN FAN MOTOR BRACKET ae THERMISTOR FIGURE 7 K Dual Capacitor The compressor and fan in all units use permanent split capacitor motors A single dual capacitor is used for both the fan motor and the compressor see unit wiring diagram The fan side of the capacitor and the compressor side of the capacitor have different mfd ratings The capacitor is located inside the unit control box see figure 4 Table 2 shows the ratings of the dual capacitor TABLE
30. on valve systems only For best results indoor temperature should be between 70 F and 80 F If outdoor temperature is 60 F 16 C or above the approach method of charging is used If outdoor tem perature is less than 60 F 16 C the subcooling method of charging is used Slight variations in charging temper ature and pressure should be expected Large variations may indicate a need for further servicing A IMPORTANT The following procedures require accurate readings of ambient outdoor temperature liquid temperature and liquid pressure for proper charging Use a thermometer with accuracy of 2 F and a pressure gauge with accuracy of 5 PSIG APPROACH METHOD SYSTEMS Ambient Temperature of 60 F 16 C or Above 1 Connect gauge manifold Connect upright HCFC 22 drum to center port of gauge manifold 2 Record outdoor air ambient temperature 3 Operate indoor and outdoor units in cooling mode Allow outdoor unit to run until system pressures stabilize 4 Make sure thermometer well is filled with mineral oil before checking liquid line temperature 5 Place thermometer in well and read liquid line tem perature Liquid line temperature should be a few degrees warmer than the outdoor air temperature Table 6 shows how many degrees warmer the liquid line temperature should be Add refrigerant to make the liquid line cooler Recover refrigerant to make the liquid line warmer TABLE 6 APPROACH
31. pera tion to defrost mode and back The control provides 14 minute defrost periods at 30 60 or 90 minute field changeable intervals The control monitors thermostat demand and holds the timer in place between thermostat demand A set of diagnostic pins are also provided for troubleshooting the unit SOLID STATE DEFROST CONTROL CMC1 22 Troubleshooting Pins Timing Pins Control Terminals Jumper FIGURE Page 6 control contains a solid state timer which switches an external defrost relay through 1 4 male spades mounted on the control s circuit board When the de frost thermostat closes call for defrost the defrost tim er initiates a 30 60 or 90 minute depending on how the control is preset timing sequence If the defrost ther mostat remains closed when the timing sequence ends the defrost relay is energized and defrost begins A defrost period can last up to 14 minutes and can be terminated two ways If the defrost thermostat does not open within 14 minutes after defrost begins the timer will de energize the defrost relay and the unit will resume normal operation If the defrost thermo stat opens during the 14 minute defrost period the de frost relay is de energized the unit resumes nor mal operation Refer to figure 9 Defrost Control Components 1 Timing Pins 30 60 90 Each of these pins provides a different timed inter val between defrosts A jumper connects the pins to c
32. r coil and out door coil with a 25 foot 7620mm line set For varying lengths of line set refer to table 5 TABLE 5 Liquid Line Ounce per 5 foot ml per mm adjust from Set Diameter 20 ft 6096mm All Sizes 3 ounce per 5 feet 90 ml per 1524 mm If line set is greater than 20 ft 6 10m add this amount If line set is less than 20 ft 6 10m subtract this amount A Leak Testing 1 Attach gauge manifold and connect a drum of dry nitrogen to center port of gauge manifold 2 Addasmallamountofrefrigerantto the lines and coil Open high pressure valve on gauge man ifold and pressurize line set and indoor coil 150 psig 1034 kPa A WARNING Danger of Explosion Can cause injury death and equipment FIGURE 18 damage When using dry nitrogen use a pres sure reducing regulator set at 150 psig 1034 kPa or less to prevent ex cessive pressure 3 Check lines and connections for leaks NOTE Ifelectronic leak detector is used add a trace of refrigerant to nitrogen for detection by leak detector 4 Release nitrogen pressure from the system cor rect any leaks and recheck B Evacuating the System Evacuating the system of non condensables is critical for proper operation of the unit Non condensables defined as any gas that will not condense under temper atures and pressures present during operation of an air conditioning system Non condensable such as water vapor combines with refr
33. rol begins timing at 0 when defrost thermostat closes Defrost is terminated when defrost relay is de energized Anytime defrost thermostat opens defrost relay is immediately de energized defrost timer resets and HOLD function stops NORMAL HEATING OPERATION DEFROST TERMINATED BY DEFROST THERMOSTAT OPEN OFF THERMOSTAT DEMAND WA DEFROST THERMOSTAT DEFROST RELAY 30 60 90 MINUTES gt 4 DEFROST THERMOSTATOPEN WITHIN 14 MINUTES NORMAL HEATING EE EL TERMINATED BY tte THERMOSTAT DEMAND DEFROST THERMOSTAT DEFROST RELAY THERMOSTAT DEMAND 7777 77777777777 VIII 22222222222 30 60 90 MINUTES PLUS HOLD TIME DEFROST THERMOSTAT DEFROST RELAY 075 6 30 60 90 MINUTES 14MIN 4 30 60 90 MINUTES i NORMAL HEATING OPERATION INTERRUPTED BY THERMOSTAT DEMAND HOLD FUNCTION DEFROST THERMOSTAT MUST REMAIN CLOSED FOR TIMER TO REMAIN IN HOLD HOLD TIME DEFROST PERIOD INTERRUPTED BY THERMOSTAT DEMAND HOLD FUNCTION THERMOSTAT DEMAND DEFROST THERMOSTAT DEFROSTRELAY 4 gt HOLD TIME 30 60 90 MINUTES 14 MIN PLUS HOLD TIME DEFROST THERMOSTAT MUST REMAIN CLOSED FOR TIMER TO REMAIN IN HOLD FIGURE 9 Page 7 4 Timing Jumper The timing jumper is a factory installed jumper on the circuit board used to connec
34. t pin W1 to one of the three timing pins The jumper may be connected to any one of the timing pins but must never be connected to either of the TST pins See Caution below DEFROST CONTROL TIMING CHANGES WARNING AVOID CONTACT WITH OTHER CON TROL TERMINALS OR CONTROL COMPONENTS WARNING DO NOT CONNECT TIMING JUMPER TO EITHER TST PIN TO CHANGE CONTROL TIMINGS 1 Turn off all power to the unit to avoid circuit board damage 2 Grasp wire connector firmly with fingers 3 Gently pull connector from 4 Select new timing pin DO NOT SELECT A TST PIN 5 Gently push connector onto desired see Table 3 for timings 6 Turn on power to unit FIGURE 10 A CAUTION Do not connect timing jumper to either TST pin TST pins are used only during atest and must not connect with any of the timing pins Control damage will result 5 TST Pins Each board is equipped with a set of test pins for use in troubleshooting the unit When jumpered to gether these pins reduce the control timing to about 1 256 original time see table 3 and figure 11 DEFROST CONTROL TEST MODE WARNING AVOID CONTACT WITH OTHER CONTROL TERMINALS OR CONTROL COMPONENTS TO PLACE CONTROL IN TEST MODE 1 Turn off all power to avoid damaging the circuit board 2 Make sure all control terminals connected as shown on unit wiring diagram before attempting to place control in test mode See N
35. thermostat de mand the compressor contactor is delayed for 8 5 se conds At the end of the delay the compressor is allowed to energize When thermostat demand is satisfied the time delay opens the circuit to the compressor contactor coil and the compressor is de energized The time delay performs no other functions Without the delay it would be possible to short cycle the com pressor A scroll compressor when short cycled can run backward if head pressure is still high It does not harm a scroll compressor to run backward but it could cause a nuisance tripout of safety limits internal over load For this reason if a TD1 1 delay should fail it must be replaced Do not bypass the control DANGER DO NOT ATTEMPT TO REPAIR THIS CONTROL UNSAFE OPERATION WILL RESULT IF THE CON TROL IS FOUND INOPERATIVE SIMPLY RE PLACE THE ENTIRE CONTROL DEFROST TIMER TD1 1 TIME DELAY CONTACTOR DEFROST RELAY TERMINAL STRIP LIQUID LINE SERVICE VALVE AND GAUGE PORT HIGH PRESSURE SWITCH VAPOR LINE SERVICE VALVE PROCESS PORT COMPRESSOR TEMPERATURE SENSOR HP25 211 THRU 461 ONLY SERVICE LIGHT THERMOSTAT CHARGE COMPENSATOR COMPRESSOR TERMINAL BOX AND GAUGE PORT SUCTION GAUGE PORT MUFFLER EXPANSION VALVE SENSING BULB REVERSING VALVE AND SOLENOID COMPRESSOR gt ACCUMULATOR HP25 511 AND 651 ONLY FIGURE 4 Page 4 D Term
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