13
Table1 – Cooling Service Analysis
PROBLEM CAUSE REMEDY
Compressora nd Condenser
Fan Will Not Start.
Power failure. Callpower company.
Fuseblown or circuitbreaker tripped. Replacefuse or reset circuit breaker.
Defective thermostat, contactor,tr ansformer,
orcontrol relay. Replacecomponent.
Insufficientline voltage. Determinecause and correct.
Incorrector faulty wiring. Check wiring diagram and rewire corr ectly.
Thermostat setting too high. Lower thermostat setting below room temperature.
CompressorWill NotStart But
CondenserFan Runs.
Faultywiring or loose connectionsin
compressor circuit. Check wiring and repair or replace.
Compressor motor burned out, seized, or
internaloverload open. De termine cause. Replace compressor.
Defectiverun/start capacitor, overload,start
relay. Determinecause and replace.
Onelegofthree---phasepowerdead. Replacefuse or reset circuit breaker. Determine
cause.
CompressorC ycles (other
than normally satisfy ing ther-
mostat).
Refrigerantovercharge or undercharge. Recoverrefrigerant, evacuate system, and recharge
tonamep late.
Defective compressor. Replaceand determine cause.
Insufficientline voltage. Determinecause and correct.
Blockedconden ser. Determinecause and correct.
Defectiverun/start capacitor, overload,or start
relay. Determinecause and replace.
Defective thermostat. Replace thermostat.
Faultyconden ser---fanmotor or capacitor. Replace.
Restrictionin refrigerant system. Locaterestriction and remove.
CompressorOperates
Continuously.
Dirtya ir filter. Replace filter.
Unitundersized for load. Decreaseload or increase unit size.
Thermostat set too low. Reset thermostat.
Lowrefrigerant charge. Locate leak; repair and recharge.
Leakingvalves in compressor. Replacecompressor.
Airin system. Recover refrigerant, evacuate system,and recharge.
Condenser coil dirty or restricted. Cleancoil or remove restriction.
ExcessiveHea d Pressure.
Dirtya ir filter. Replace filter.
Dirtycond enser coil. Clean coil.
Refrigerantovercharged. Recoverexcess refrigerant.
Airin system. Recover refrigerant, evacuate system,and recharge.
Condenserair restricted or air short---cycling. Determinecause and correct.
HeadPre ssure TooLow.
Lowrefrigerant charge. Check for leaks; repair and recharg e.
Compressor valves leaking. Replace compressor.
Restrictioninliquidtube. Removerestriction.
ExcessiveSuction Pressu re.
Highhead load. Checkforsource and eliminate.
Compressor valves leaking. Replace compressor.
Refrigerantovercharged. Recoverexcess refrigerant.
SuctionPressure Too Low.
Dirtya ir filter. Replace filter.
Lowrefrigerant charge. Check for leaks; repair and recharg e.
Metering device or low side restricted. Removesource of restriction.
Insufficientevaporator airflow. Increaseair quantity. Check filterand replace if
necessary.
Temperaturetoo low in conditioned area. Resetth ermostat.
Outdoor ambient below 25˚F. Installlow ---ambientkit.
EvaporatorFan Will Not Shut
Off. Timeoff delay not finished. Wai t fo r 30 ---s e c o n d of f d e la y.
CompressorM akes Excessive
Noise. Compressorrotating in wrong direction. Reversethe3---phasepowerleads.
48TC