SERVICING
COOLING /HEAT PUMP- SERVICE ANALYSIS GUIDE
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| No Cooling |
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| Unsatisfactory Cooling/Heating |
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| Pressures |
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| ProcedureServiceSee Ref. |
POSSIBLE CAUSE | notwillSystemstart | FanCond.andComp.will not start | willfanEvaporatornot start | willfanCondensernot start | oncyclesCompressoroverload | toothenandcoolToowarm | warmonenoughcoolNot days | otherscool,tooareasCertaintoo warm | noisyisCompressor | terminatenotwillUnitdefrost | defrostnotwillUnit | pressuresuctionLow | pressureheadLow | pressuresuctionHigh | pressureheadHigh | Test Method Remedy | |||||
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DOTS IN ANALYSIS GUIDE |
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INDICATE SYMPTOM |
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"POSSIBLE CAUSE" |
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Pow er Failure | • |
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| Test Voltage | |
Blow n Fuse | • |
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| Inspect Fuse Size & Type | |
Unbalanced Pow er, 3PH |
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| Test Voltage | |
Loose Connection | • |
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| Inspect Connection - Tighten | |
Shorted or Broken Wires | • | • | • | • | • | • |
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| Test Circuits With Ohmmeter | |
Open Fan Overload |
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| Test Continuity of Overload | |
Faulty Thermostat | • |
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| Test continuity of Thermostat & Wiring | |
Faulty Transformer | • |
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| Check control circuit w ith voltmeter | |
Shorted or Open Capacitor |
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| Test Capacitor | |
Internal Compressor Overload Open |
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| Test Continuity of Overload | |
Shorted or Grounded Compressor |
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| Test Motor Windings | |
Compressor Stuck |
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| Use Test Cord | |
Faulty Compressor Contactor |
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| Test continuity of Coil & Contacts | |
Compressor High Stage Not Working |
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| Test Voltage to Unloader Plug, Test Plug | |
Open Control Circuit |
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| Test Control Circuit w ith Voltmeter | |
Low Voltage |
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| Test Voltage | |
Faulty Evap. Fan Motor |
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| ♦ | Repair or Replace | |
Shorted or Grounded Fan Motor |
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| • | Test Motor Windings | |
Improper Cooling Anticipator |
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| Check resistance of Anticipator | |
Shortage of Refrigerant |
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| Test For Leaks, Add Refrigerant | |
Restricted Liquid Line |
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| • | Remove Restriction, Replace Restricted Part | |
Open Element or Limit on Elec. Heater |
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| Test Heater Element and Controls | |
Dirty Air Filter |
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| ♦ | Inspect |
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Dirty Indoor Coil |
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| ♦ | Inspect Coil - Clean |
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Not enough air across Indoor Coil |
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| ♦ | Check Blow er Speed, Duct Static Press, Filter | |
Too much air across Indoor Coil |
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| Reduce Blow er Speed | |
Overcharge of Refrigerant |
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| • | • | Recover Part of Charge | |
Dirty Outdoor Coil |
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| • | Inspect Coil - Clean |
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Noncondensibles |
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| • | Recover Charge, Evacuate, Recharge | |
Recirculation of Condensing Air |
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| • | Remove Obstruction to Air Flow |
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Infiltration of Outdoor Air |
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| Check Window s, Doors, Vent Fans, Etc. |
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Improperly Located Thermostat |
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| Relocate Thermostat |
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Air Flow Unbalanced |
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| Readjust Air Volume Dampers |
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System Undersized |
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| Refigure Cooling Load |
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Broken Internal Parts |
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| Replace Compressor | |
Broken Valves |
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| Test Compressor Efficiency | |
Inefficient Compressor |
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| Test Compressor Efficiency | |
Loose |
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| Tighten Bolts |
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Faulty Reversing Valve |
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| ♦ | ♦ | ♦ | Replace Valve or Solenoid | |
Faulty Defrost Control |
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| ♦ | Test Control | |
Faulty Defrost Thermostat |
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| ♦ | ♦ | ♦ | ♦ | ♦ | ♦ | ♦ | Test Defrost Thermostat | |
Flow rator Not Seating Properly |
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| Check Flow rator & Seat or Replace Flow rator | |
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| • Cooling or Heating Cycle (Heat Pump) |
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| ♦ Heating Cycle Only (Heat Pump) |
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