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A LOOK AT SERVICE SAFETY

Servicing

77

Step 1: Before Continuing with 

Troubleshooting...

WARNING!

 

A

ll electric power should be disconnected and you

should have already made sure that the compressor does not
have a ground fault (see “Checking for a Ground Fault” on
pages 47-48). 

You should have also checked the windings for con-

tinuity and proper resistance (see “Checking for Continuity and
Proper Resistance” on pages 48-49), made sure the system is get-
ting proper voltage, and that the control, thermostat, and contac-
tor are working properly. 

Step 2:  Disconnect Fan Motor or Any 

Other Devices

If there is a fan motor or any other auxiliary device, open the cir-
cuit for the fan motor or any other device.

Step 3:  Check Run Capacitor

CAUTION: 

Using a 20,000 ohm resistor, discharge the capaci-

tor before removing it from the system to avoid damage to mea-
suring devices and risk of electric shock.

 Disconnect the run

capacitor from the system. Use a capacitance meter to check
capacitor. Capacitance should be ±10% of the marked capacitor
value.

As an alternative, check the run capacitor by measuring continuity
across the capacitor terminals:

a. Rx1 scale: If there is continuity, then the run capacitor is

shorted and needs to be replaced.

b. Rx100,000 scale: If there is no needle deflection on an

analog meter or if a digital meter indicates infinite resis-
tance, then the run capacitor is open and needs to be
replaced.

Possible reasons that a run capacitor is not working properly
include: 

Use of incorrect run capacitor. Replace with proper run
capacitor. 

Line voltage is too high (greater than 110% of rated volt-
age).
 

Step 4:  Check Wired-in PTC Relay

Check the relay by measuring continuity between the pin holes
where the R and S pins on the compressor are inserted. If there is
no continuity, the relay may be open. Wait 3 minutes, then check
continuity again. If there is still no continuity, replace the relay.

Step 5:  Check External Thermal 

Protector

Check the external thermal protector by measuring continuity
between the power-in terminal and the female C (common) ter-
minal pin. If there is no continuity, the thermal protector may be
tripped. Wait at least 5 minutes, then check continuity again. If
there is still no continuity, replace the thermal protector.

Step 6:  Continue Troubleshooting

If all above tests prove satisfactory and unit still fails to operate
properly, check for adequate compressor pumping as outlined in
the procedure on page 83.

Summary of Contents for AEA4440YXA

Page 1: ...Service Data Book Sold By American Refrigeration Supplies Inc Wholesale Distribution North America...

Page 2: ...sonnel Only 2 III Terminal Venting and Electrocution 2 IV Refrigerants and Other Chemicals 4 V Compressor Removal 4 VI System Flushing Purging and Pressure Testing for Leaks 4 VII System Charging 5 VI...

Page 3: ...n lead to serious burns or death When spray from ter minal venting is ignited this is called terminal vent ing with ignition See Figures 1 1 through 1 3 for detail B Terminal Venting and Electrocution...

Page 4: ...up view of hermetic terminal showing individual terminal pins with power leads removed Figure 1 3 Close up view of hermetic terminal after it has vented Figure 1 4 Compressor with 1 protective termin...

Page 5: ...ngs this can Cause a variety of injuries including burns and frostbite Cause a fire if a torch is used to discon nect tubing Expose the service person to toxic gas To avoid serious injury or death be...

Page 6: ...rogen cylinder and release the pressure in the system before connecting a refrigerant container to the system The higher pressure gas in the system can explode the refrigerant container VII System Cha...

Page 7: ...s a leak water can enter the refrigerant side of the system Water entering the refrigerant side can come in contact with live electrical connections in the compressor causing a short circuit or a path...

Page 8: ...ter Utilizing System If you do not find any indication of a history of loss of charge without detection of a leak you still need to install a high pressure cut out which interrupts power to ALL leads...

Page 9: ...E SAFETY 9 2 MODEL AND APPLICATION INFORMATION I Compressor Model Number Codes 10 II Condensing Unit Model Number Codes 11 III Serial Label Information 12 IV Basic Application Information for Hermetic...

Page 10: ...cation 4 in the unit s model number Motor Starting T orque Normal High Normal High Normal Normal High Normal High Normal Normal Rating Pt 10 F 10 F 45 F 45 F 45 F 20 F 20 F 49 F 20 F 20 F 20 F Primary...

Page 11: ...rcial Design N Advanced Commercial Design S Customer Special T Interconnect Compressor U Water Cooled Adv Commercial Design V Electrical Special Conduit Design W Water Cooled Unit X Interconnect Unit...

Page 12: ...the same location Both describe the characteristics of the compressor The months are identified as identified in Table 2 1 Figure 2 3 Compressor serial label AH301FT 077 SE1490C V230 208Hz60 V200 Hz50...

Page 13: ...SIDE DESIGN PRESSURE P S I MIN CIRCUIT AMPACITY F L A E A PH 60 HZ 50 HZ 58 8 8 8 1 0J00066332 2C234 9 AKA9446EXAXC 1 4 20 R 22 444 12 4 350 150 1 115 10F TO 45F 35W SER EM MOD 1P MADE IN USA 1 THERMA...

Page 14: ...rigerant Use only the serial label refrigerant when charging the system Using a different refrigerant can lead to excess system pressure damage to the compressor and an explosion For example using R 5...

Page 15: ...MOTOR AND COMPONENT INFORMATION I Single Phase Compressor Motor Types 16 II PSC Motor Starting 18 III Hermetic Compressor Thermal Protectors 19 IV Compressor Motor Starting Relays 27 V Selecting Capac...

Page 16: ...ding as the motor comes up to design speed Three types of relays are used with this motor a current relay a wired in Positive Temperature Coefficient PTC relay or a module Positive Temperature Coeffic...

Page 17: ...start capacitor or relay is necessary For addi tional starting torque a proper start assist kit may be added see Figure 3 6 Some start assist kits may include a wired in Positive Temperature Coeffici...

Page 18: ...tion pressures must be equal and not more than 170 psig Refrigeration metering device cap tube or TX valve should equalize system pres sures within 3 minutes Unequal system pres sure may be caused by...

Page 19: ...ressor housing quickly senses any unusual temperature rise or excess current draw The bi metal disc within the thermal protec tor see Figure 3 9 reacts to either excess tempera ture and or excess curr...

Page 20: ...pplication Make no substitutions Will not protect motor if compressor is operated outside its evaporator temperature range Internal Line Break Thermal Protectors Currently used on all AH AB AV AG AW a...

Page 21: ...arge gas temperatures Notes on the compressor electronic protection sys tem The compressor will not run if a jumper is placed across terminals S and S1 Terminals M1 and M2 are a normally closed switch...

Page 22: ...t Compressor Sensors Compressor Power To Control Circuit Contactor Coil S1 C1 L1 L2 L3 R1 R2 R3 C2 S Table 3 3 AN Wiring on Typical System Model AN5590E F AN5610E F AN5612E F AN5614E F 8 TW 8 TW 6 TW...

Page 23: ...t To M2 14 Min See Table 3 4 Use Copper Conductors Only 24 Volt Compressor Sensors Compressor Power To Control Circuit Control Line 230V 15AA1104C Electronic Protection Module S1 C1 L1 L2 L3 R1 R2 R3...

Page 24: ...590G H AN5610G H AN5612G H AN5614G H 230 200 60 3 230 200 60 3 230 200 60 3 230 200 60 3 460 60 3 460 60 3 460 60 3 460 60 3 8 TW 8 TW 8 TW 6 TW 12 TW 12 TW 10 TW 10 TW 92 500 100 000 122 000 140 000...

Page 25: ...25 E Small Terminal Block with Thermal Protector Figure 3 15 Small terminal block wiring on typical system with thermal protector T1 T2 T3 L1 L2 L3 Crankcase Heaters To Control Circuit Clear Tie Compr...

Page 26: ...Tie Ground T1 M 1 T 1 M 2 S 1 S 2 T 2 To Protection Module Line Circuit Electronic Protection Module 15AA1104 See Table 3 6 Control Line 2 5A Max 24 115 230 V A C 3 PH Incoming Power Texas Instrument...

Page 27: ...PTC Type Relay Solid state technology has made available another type of current sensitive relay a PTC starting switch Certain ceramic materials have the unique property of greatly increasing their r...

Page 28: ...Motor Type Characteristics Current Relay RSIR and CSIR Sense starting current to main run windings Contacts normally open Contacts close and then release in less than 1 second as motor starts Must be...

Page 29: ...rovided in Figures 3 20 and 3 21 Figure 3 20 Explanation of GE Potential Relay Code 3ARR3 A 3 Potential Relay Type Mounting Position C Number of Terminals and Bracket 5 Coil Group Continuous Voltage C...

Page 30: ...nder cover See note on page 31 1 Face down 2 Face up 3 Face out horizontal numbers upside down 4 Face out 90 clockwise from number 3 position 5 Face out horizontal numbers right side up 6 Face out 90...

Page 31: ...the relay is to be mounted It is of utmost importance that the relay be mounted in the required posi tion Mounting in any other position can change the relay s operating characteristics enough so tha...

Page 32: ...Do not add excessive starting capacitance C Run Capacitors Since January 1979 capacitors provided by Tecum seh have contained non PCB oils or have been con structed using non PCB impregnated metalliz...

Page 33: ...d may reduce start torque Capacitors in CSR motors should have 15 000 ohm 2 watt bleed resistor across terminals Capacitor rated voltage must be equal to or more than that speci ed Capacitor MFD shoul...

Page 34: ...ve terminal cover While the protective ter minal cover may identify the terminal pins it is pri marily designed to reduce the risk of serious injury or death from electrocution or terminal venting wit...

Page 35: ...ls Screw On Type Terminal Pins AN Terminals Figure 3 24 Current arrangements continued Common Run C S R T3 T1 T2 Start Run 1 Phase L3 3 Phase L2 3 Phase L1 3 Phase Common 1 Phase Start 1 Phase 24 Volt...

Page 36: ...se or circuit breaker used to protect against short circuit and or ground fault of a unit utilizing a hermetic compressor shall be no more than the sum of 225 of the compressor Related Load Amps RLA a...

Page 37: ...38 II Servicing or Troubleshooting Water Utilizing Systems Preventing Explosions 39 III Troubleshooting Chart 41 IV Identifying Compressor Electrical Problems 47 V Checking for Adequate Compressor Pum...

Page 38: ...d follow the General Service Safety Precautions on pages 2 7 Before servicing THINK SAFETY Disconnect ALL electrical power before removing the protective terminal cover Never energize the system unles...

Page 39: ...check to see if it has either a pressure relief valve or a high pressure cut out as previously described If the system does not have at least one of these DISCONNECT ALL ELECTRICAL POWER and look for...

Page 40: ...the water inside the heat exchanger The entire system must be replaced See Replacing a Single Wall Water Utiliz ing System below If you do not find any indication of a history of loss of charge withou...

Page 41: ...stions about returns under war ranty see Is your Compressor Eligible for Return Under Warranty on page 83 Complaint Possible Causes Response A Compressor will not start no hum 1 System component not f...

Page 42: ...e accumulator will prevent liquid refrigerant from getting into the compressor 6 Internal mechanical trouble in compressor See Checking for Adequate Compressor Pumping on page 83 C Compressor starts b...

Page 43: ...ical problems such as thermal protector or run capacitor not working properly See Identifying Compressor Electrical Problems on page 47 4 Discharge pressure too high If this is a water utilizing syste...

Page 44: ...device a Refer to the OEM service information b Same as a c Same as a F Unit operates long or continuously 1 Undercharge of refrigerant If this is a water utilizing system see Servicing or Troubleshoo...

Page 45: ...ms Preventing Explosions on page 39 Also refer to the OEM service information H Suction line frosted or sweating System problems such as a expansion valve passing excess refrigerant or is oversized b...

Page 46: ...ak into refrigerant side of a water utilizing system See Servicing or Troubleshooting Water Utilizing Systems Preventing Explosions on page 39 Also refer to the OEM service information K System rattle...

Page 47: ...nal cover Never energize the system unless the protective terminal cover is securely fastened and the compressor is properly connected to ground Never reset a breaker or replace a fuse without first c...

Page 48: ...or short circuit in the motor windings or if the heater element of the thermal protector is open Use the procedure in Table 4 1 to check single and 3 phase motors Why use a megger or Hi Pot Tecumseh P...

Page 49: ...d S C and R and S and R Add the resistance between C and S to the resistance between C and R This sum should equal the resistance found between S and R A small deviation in this comparison is acceptab...

Page 50: ...rocedure for the compressor you are servicing For more information on Compressor motor types see Single Phase Compressor Motor Types on pages 16 17 Thermal protectors see Hermetic Compressor Thermal P...

Page 51: ...m seh Electrical Service Parts Guide Book for informa tion on proper replacement parts or call Tecumseh Products Company at 1 800 211 3427 Thermal Protector Type Relay Type Capacitor Type Internal Ext...

Page 52: ...hermal protector If there is no continuity then the thermal protector may be tripped Wait at least 5 minutes then check continuity again If there is still no continuity replace the thermal protector S...

Page 53: ...arts Guide Book for informa tion on proper replacement parts or call Tecumseh Products Company at 1 800 211 3427 Thermal Protector Type Relay Type Capacitor Type Internal External Current Potential PT...

Page 54: ...r any other device Step 3 Check Wired in PTC Relay Check the relay by measuring continuity between the pin holes where the R and S pins on the compressor are inserted If there is no continuity the rel...

Page 55: ...al Service Parts Guide Book for informa tion on proper replacement parts or call Tecumseh Products Company at 1 800 211 3427 Thermal Protector Type Relay Type Capacitor Type Internal External Current...

Page 56: ...tector Check the external thermal protector by measuring continuity between C and L on the starting and protector package If there is no continuity the thermal protector may be tripped Wait at least 5...

Page 57: ...e Parts Guide Book for informa tion on proper replacement parts or call Tecumseh Products Company at 1 800 211 3427 Thermal Protector Type Relay Type Capacitor Type Internal External Current Potential...

Page 58: ...een a Relay terminals 1 and S If there is continuity then the relay contacts are closed when they should be open Replace the current relay b Relay terminals 2 and M If there is no continuity replace t...

Page 59: ...he compressor s thermal protector or sys tem components such as the thermostat control contac tor or high or low pressure cut out For more information on troubleshooting the thermal protector see Step...

Page 60: ...rma tion on proper replacement parts or call Tecumseh Products Company at 1 800 211 3427 Thermal Protector Type Relay Type Capacitor Type Internal External Current Potential PTC Run Start Other auxili...

Page 61: ...k Wiring Confirm that there is continuity between a The power input terminal on the thermal protector and 5 on relay b The protector common lead wire and C Step 5 Check Potential Relay Before checking...

Page 62: ...ged operation on start cycle due to low voltage Determine if the line voltage is too low less than 90 of rated voltage Prolonged operation on start cycle due to incorrect relay Replace with correct re...

Page 63: ...rvice Parts Guide Book for informa tion on proper replacement parts or call Tecumseh Products Company at 1 800 211 3427 Thermal Protector Type Relay Type Capacitor Type Internal External Current Poten...

Page 64: ...rect relay Replace with correct relay Line voltage is too high or low greater than 110 or less than 90 of rated voltage Excessive short cycling Short cycling can be caused by problems with the compres...

Page 65: ...is outside of this range then the start capacitor needs to be replaced As an alternative check the start capacitor by measuring conti nuity between relay terminals 1 and 4 a Rx1 scale If there is con...

Page 66: ...ector If there is no continuity and Steps 1through 4 have been completed allowing the thermal protector sufficient time to reset replace the ther mal protector Step 6 Check Wiring Confirm that there i...

Page 67: ...ernal External Current Potential PTC Run Start Figure 4 8 CSR compressor motor type with internal thermal protector without start winding protection potential relay and run and start capacitors Relay...

Page 68: ...e internal thermal protector may be tripped Wait for it to cool off and close This may take more than an hour Check continuity again If there is replace the compressor Step 3 Check Run Capacitor CAUTI...

Page 69: ...tion due to loose relay mounting Tighten relay mounting Use of incorrect run capacitor Replace with proper run capacitor Step 5 Check Start Capacitor CAUTION Using a 20 000 ohm resistor discharge the...

Page 70: ...s thermal protector or sys tem components such as the thermostat control contac tor or high or low pressure cut out For more information on troubleshooting the thermal protector see Step 3 For trouble...

Page 71: ...actual relay to locate the terminals If replacement parts are needed refer to the Tecum seh Electrical Service Parts Guide Book for informa tion on proper replacement parts Thermal Protector Type Rel...

Page 72: ...place the thermal protector Step 4 Check Run Capacitor CAUTION Using a 20 000 ohm resistor discharge the capacitor before removing it from the system to avoid damage to measuring devices and risk of e...

Page 73: ...leshooting If all above tests prove satisfactory and unit still fails to operate properly check for adequate compressor pumping as outlined in the procedure on page 83 Figure 4 11 PSC compressor motor...

Page 74: ...pe Capacitor Type Internal External Current Potential PTC Run Start Figure 4 12 PSC compressor motor type with internal thermal protector without start winding protection and run capacitor Compressor...

Page 75: ...nuity replace the compressor Step 3 Check Run Capacitor CAUTION Using a 20 000 ohm resistor discharge the capaci tor before removing it from the system to avoid damage to mea suring devices and risk o...

Page 76: ...informa tion on proper replacement parts or call Tecumseh Products Company at 1 800 211 3427 Thermal Protector Type Relay Type Capacitor Type Internal External Current Potential PTC Run Start wired Fi...

Page 77: ...r terminals a Rx1 scale If there is continuity then the run capacitor is shorted and needs to be replaced b Rx100 000 scale If there is no needle deflection on an analog meter or if a digital meter in...

Page 78: ...n on proper replacement parts or call Tecumseh Products Company at 1 800 211 3427 Thermal Protector Type Relay Type Capacitor Type Internal External Current Potential PTC Run Start module plug in Figu...

Page 79: ...em Use a capacitance meter to check capacitor Capacitance should be 10 of the marked capacitor value As an alternative check the run capacitor by measuring conti nuity across the capacitor terminals C...

Page 80: ...compressor are inserted If there is no continuity the relay may be open Wait 3 minutes then check continuity again If there is still no continuity replace the protector package Step 6 Continue Trouble...

Page 81: ...to the Tecumseh Electrical Service Parts Guide Book for information on proper replacement parts or call Tecumseh Products Company at 1 800 211 3427 Figure 4 16 3 phase motor with solid state protecti...

Page 82: ...that the control thermo stat and contactor are working properly Step 2 Allow Thermal Protector to Reset When servicing 3 phase motors be sure to allow time for the internal thermal protector to reset...

Page 83: ...s down and exam ines a representative sample of compressors returned by authorized wholesalers and notes the reason for failure In the field it can be determined if a compressor is eligible for return...

Page 84: ...84 Chapter 4...

Page 85: ...ube Connections 86 II Refrigerant Line Sizes 88 III Refrigerant Line Pressure Drops 93 IV Refrigerant Line Velocities 98 V Service Valves 103 VI Processing the System 103 VII System Cleanup and Compre...

Page 86: ...ation of compressor connections can usually be accomplished without difficulty however occa sionally some question arises concerning oil cooler tubes and process tubes Oil cooler tubes are found only...

Page 87: ...lation and Replacement Information 87 Figure 5 1 Standard discharge tubing arrangements continued AK Air Conditioning Discharge Tube Discharge Tube Discharge Tube Discharge Tube Discharge Tube Dischar...

Page 88: ...l trapping in the evaporator If because of the spillover the return gas is wet at the compressor a suction line accumulator should be installed adjacent to the compressor On systems with evaporators b...

Page 89: ...1 8 1 3 8 1 1 8 1 1 8 1 2 36000 3 1 8 2 1 8 1 5 8 1 3 8 1 1 8 1 2 48000 3 5 8 2 5 8 2 1 8 1 5 8 1 3 8 1 2 60000 3 5 8 2 5 8 2 5 8 1 5 8 1 3 8 1 2 72000 4 1 8 3 1 8 2 5 8 2 1 8 1 5 8 1 2 Table 5 2 R 22...

Page 90: ...traps are not required Horizontal suction lines are sized larger to reduce pressure drop Suction line lengths in excess of 100 are not recommended On heat pump systems the lines serving as both a dis...

Page 91: ...bles 5 4 and 5 5 show recommended suction line sizes for installations where that line is horizontal or down flow In the event the suction line is up flow use one standard size smaller EXAMPLE Where a...

Page 92: ...3 4 5 8 1 2 1 2 1 4 4800 1 1 8 7 8 3 4 5 8 1 2 1 4 6000 1 1 8 7 8 3 4 5 8 1 2 1 4 7200 1 3 8 1 1 8 7 8 3 4 5 8 1 4 8400 1 3 8 1 1 8 7 8 3 4 5 8 3 8 9600 1 5 8 1 1 8 7 8 3 4 5 8 3 8 10800 1 5 8 1 3 8 1...

Page 93: ...e Drop 1 0 p s i 100 ft At 120 F Condenser At 100 F Condenser At 80 F Condenser 6 1 8 5 1 8 4 1 8 3 5 8 3 1 8 2 1 8 1 5 8 1 1 8 7 8 3 4 5 8 1 2 3 8 6 0 F E v a p o r a t o r T e m p e r a t u r e 4 0...

Page 94: ...r a t u r e 4 0 F 1 3 8 O D T y p e L C o p p e r T u b i n g 3 1 8 2 1 8 Tons of Refrigeration Pressure Drop In Lbs Per Sq In Per 100 Ft EXAMPLE 5 5 Tons at 40 F Evap 85 F Cond 2 5 8 Suction Line Pre...

Page 95: ...enser At 100 F Condenser At 120 F Condenser 7 1 8 6 1 8 5 1 8 4 1 8 3 5 8 3 1 8 2 5 8 2 1 8 1 5 8 1 3 8 1 1 8 7 8 3 4 1 2 3 8 5 8 O D T y p e L C o p p e r T u b i n g 6 0 F E v a p o r a t o r T e m...

Page 96: ...g 5 1 8 4 1 8 3 5 8 3 1 8 2 5 8 2 1 8 1 5 8 1 3 8 1 1 8 7 8 3 4 5 8 1 2 3 8 5 0 C E v a p o r a t o r T e m p e r a t u r e s 4 0 C 2 0 C 0 C 3 0 C 1 0 C 1 0 C D i s c h a r g e L i n e s L i n e s L...

Page 97: ...p o r a t o r T e m p e r a t u r e 4 0 F 2 0 F 2 0 F 4 0 F D i s c h a r g e L i n e s L i q u i d L i n e s 0 F 5 1 8 4 1 8 3 5 8 3 1 8 2 5 8 2 1 8 1 5 8 1 3 8 1 1 8 7 8 3 4 5 8 1 2 3 8 Pressure Dro...

Page 98: ...F Condenser EXAMPLE 5 5 Tons at 40 F Evap 85 F Cond 3 1 8 Suction Line Velocity 1916 ft min 3 4 Liquid Line Velocity 94 ft min At 100 F Condenser At 120 F Condenser 6 1 8 6 0 F E v a p o r a t o r T...

Page 99: ...enser At 100 F Condenser At 120 F Condenser 5 1 8 4 1 8 6 0 F E v a p o r a t o r T e m p e r a t u r e D i s c h a r g e l i n e s 8 0 F C o n d e n s e r 4 0 F 2 0 F 2 0 F 4 0 F L i q u i d L i n e...

Page 100: ...enser At 100 F Condenser At 120 F Condenser 6 1 8 1 5 8 1 3 8 1 1 8 7 8 3 4 5 8 1 2 3 8 5 1 8 4 1 8 3 5 8 3 1 8 2 5 8 2 1 8 6 0 F E v a p o r a t o r T e m p e r a t u r e 4 0 F 2 0 F 0 F 2 0 F 4 0 F...

Page 101: ...denser At 50 C Condenser 6 1 8 O D T y p e L C o p p e r T u b i n g 5 1 8 4 1 8 3 5 8 3 1 8 2 5 8 7 8 3 4 5 8 3 8 1 2 2 1 8 1 5 8 1 1 8 1 3 8 5 0 C E v a p o r a t o r T e m p e r a t u r e s 4 0 C 3...

Page 102: ...uid Line Velocity 0 37 m s NOTE Liquid line determined at 20 C evap and 30 C cond Discharge lines at 20 C evap Other conditions do not appreciably change result Net refrigeration for HFC 134a includes...

Page 103: ...nd scale forming inside the tubes it is good practice to flow dry nitro gen through the tubing during the soldering operations A light flow of about 1 4 cubic feet per minute is sufficient 3 Install a...

Page 104: ...it does not mean that a fire actu ally occurs inside a hermetic compressor Even small amounts of contamination must be removed from the system to avoid damaging the replacement compressor Therefore it...

Page 105: ...of the accumulator and the compressor In the case of Compressor Housing Contami nation the filter drier should be installed between the compressor and the suction line accumulator Rubber refrigeratio...

Page 106: ...l be mea sured Change the suction filter drier and the liquid line filter drier whenever the pressure drop approaches or exceeds that allowed for temporary operation during cleanup see Table 5 4 Keep...

Page 107: ...s A reading of less than 0 05 acid number is an indication that the sys tem is free of acid A reading of higher than 0 05 means continued cleaning is required Return to B2 on page 105 G Monitor the Sy...

Page 108: ...zing systems that have single wall heat exchangers may present a risk of explosion Such systems may include water source heat pump air conditioning sys tems and water cooling systems such as icemakers...

Page 109: ...to the Compressor During Shutdown 110 II Crankcase Heaters 113 III Starting a System with Liquid Refrigerant in the Compressor 114 IV Control of Liquid Refrigerant Floodback to the Compressor During...

Page 110: ...Products Company A five ton split air conditioning system was used with a four inch sight glass installed in the compressor housing The condensing unit and evaporator sec tion were connected by appro...

Page 111: ...3 Five seconds after start up violent foaming action lls sight glass as refrigerant boils away taking oil charge with it Figure 6 4 More than 60 seconds after start up oil level is well below normal...

Page 112: ...s while operating This con dition can be controlled by the application of a suc tion line accumulator Crankcase heat does nothing to prevent liquid floodback and an accumulator does nothing to prevent...

Page 113: ...m tempera ture of 80 F The immersion type heater is factory assembled and is presently used with AB AW AG AV and AN compressors It is self regulating and energy effi cient In the run capacitance off c...

Page 114: ...ne to two seconds then wait 1 to 2 minutes After 3 or 4 jogs apply power contin uously WARNING Jogging a compressor that has an electrical problem can increase the likeli hood of terminal venting To r...

Page 115: ...t in an accumulation of the refrigerant under the oil see Figure 6 10 Thus when the compressor is started the first liquid to be pumped to the bearings will probably be refrigerant not oil Even if thi...

Page 116: ...han 60 seconds after start up oil level is well below normal operating levels a condition that is an important factor in compressor bearing wear Figure 6 11 Five seconds after start up violent foaming...

Page 117: ...cumulation in the compressor can also be caused by liquid migration to the compressor during periods of shutdown This condition can be controlled by the application of a crankcase heater A suction lin...

Page 118: ...temperature and capacity in tons of refrigeration These factors were considered in the design and test ing of the accumulator If on older systems the system refrigerant charge is not known consider th...

Page 119: ...ere The IPR valve may also open to relieve hydraulic pressures in the event of slugging This is apt to occur on startup if refrigerant has been allowed to migrate to the compressor crankcase It is a c...

Page 120: ...120 Chapter 6...

Page 121: ...LOOK AT SERVICE SAFETY Appendix 121 APPENDIX I The Basic Refrigeration Cycle 122 II Example of a Tecumseh Hermetic Compressor 124 III Capillary Tube Sizing 126 IV Approved Hermetic Compressor Oils 12...

Page 122: ...ential across the expansion device or in the case of a thermal expansion valve by the degree of superheat of the suction gas Thus the thermal expansion valve shown requires a sensor bulb located at th...

Page 123: ...Receiver Tank Condenser Fan T X Valve Sensor Bulb Expansion Valve or Capillary Tube Strainer Drier Low Pressure Side Low Pressure Gas High Pressure Gas Low Pressure Liquid High Pressure Liquid Evapor...

Page 124: ...frigerant gas surrounds the compressor crankcase and motor as it is drawn through the compressor housing and into the cylinder s through the suction muffler and suction valves As the gas is pressured...

Page 125: ...A LOOK AT SERVICE SAFETY Appendix 125 Figure A 2 Internal view of typical air conditioning compressor...

Page 126: ...Capacity BTU Hr Condenser Type Normal Evaporating Temperature 10 TO 5 F 5 TO 20 F 200 300 Static or Fan 16 026 10 026 300 400 Static or fan 12 026 12 031 400 700 Static 12 031 12 036 Fan 10 031 10 036...

Page 127: ...12 042 1800 2500 Fan 12 042 12 049 8 049 2500 3500 Fan 10 042 10 049 3500 4000 Fan 12 049 10 054 4000 5000 Fan 10 054 10 059 5000 6000 Fan 12 059 12 064 6000 7000 Fan 10 059 10 064 12 070 7000 10000...

Page 128: ...ding per circuit becomes 6100 BTU Hr Use 40 x 049 or 75 x 054 if the intention is to feed each circuit with a separate cap tube Fewer number of cap tubes are optional of course Assuming a 1 2 OD tube...

Page 129: ...in accordance with good engineering practice Some system designs containing unusual evapora tors and or extensive interconnected piping may require additional oil However since excess oil can also dam...

Page 130: ...cal Zerol 300 Soltex SA56 Petrobras CP32RHS Napthenic Paraf nic Witco LP200 Penreco Sontex 200LT A LT Paraf nic Total A68 Polyol Ester Emkarate RL32S Mobil EAL Arctic 32 22 Cognis ProEco 32ML Castrol...

Page 131: ...arge oz AB all 32 AEA 1360 80 10 16 AE all others 10 AG 65 AHA2466 80 38 AH all others 45 AJ 26 AK 17 AN 140 AV 54 AWA 2XXX 7XXX 9XXX 38 AWE all others 32 AWF all others 32 AWG J all others 38 AZA 320...

Page 132: ...132 Appendix...

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