Tempcool TC-120B4 - Troubleshooting Guide; Unit Operation Problems

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shoulddeflect0.25incheswith3poundsof
pressure.Newbeltscanloosenduringthefirst
hoursofoperation,sorecheckthebeltsafter
thefirst10hoursofoperationandthencheck
annually.Beltsshouldbereplacediftheyare
crackedorglazed.Driveshouldbereplacedif
they
aregroovedorworn.
Blowerfanbladescanbecomedirtyespecially
whenoperatingdirtyenvironmentswithout
filter.Thedirtwillbuilduponthebacksideof
thebladesandshouldbecleanoffitstartsto
cakeon.Fanperformanceisreducediflarge
quantitiesofdirtareonthe
blades.
SheaveAdjustment:
The condenser fan on the TC-120B series of air
conditioners utilizes an adjustable sheaves on
the motor to drive the blowers. The sheave is
preset at the factory and should not be adjusted.
However the blower, motor and drives should
periodically be checked for tightness and align-
ment. Check the setscrews that connect the
sheaves and blower wheel to the shafts to make
sure they are secure. Make sure the setscrews
locking down the adjustable flange on the motor
sheave are secure.
TROUBLESHOOTINGGUIDE
Problem Cause Remedy
Unitdoesnotrun
PhaseLightoff.
PowerLightdoesnot
comeon
Nopower Checkpowersupplyforcorrectvoltageandphase
CircuitbreakerOFF SwitchunitcircuitbreakerON
OFF–ONswitchOFF SwitchOFF–ONswitchtoON
Unitdoesnotrun.
PhaselightisON
Incomingpoweris out of
phasewiththeunit
Interchangeanytwolegsofthesupplypowerattheunit
circuitbreaker.Thelightshouldnotturnon.
Unitdoesnotrun.
PowerLightON
PhaseLightOFF
CondensateLightOFF
Thermostatnot
connected.
Plugthermostatplugintoreceptacleonsideofunit.
Thermostatnotsetto
COOLorsetpoint
temperatureabove
currenttemperature.
SetthermostattoCOOLandadjustthetemperature
settingbelowthecurrentthermostattemperature.The
air‐conditionershouldstart
Thermostatincorrectly
wiredordefective
Checkthermostat,cordandplugwiring.Replace
thermostatifdefective.
Unitdoesnotrun
CondensateLightON
Condensatepumpnot
working.
Checkwiringtocondensate pump.Repairorreplace
condensatepumpifrequired.
Callforcooling.
Evaporatorfanruns,
butcompressorand
condenserfandon’t
ControllerGreenlight
ON
Compressor2minute
timedelayedstartactive
Waitfortwominutestoseeifcompressorandfanstart
Thermostatinnotin
coolingmode
ChangethermostattoCOOL.Theremaystillbeatwo
minutedelayuntilthecompressorstarts.
ControllerLockout RefertoCopelandDigitalCompressorTroubleshooting
guideatthebackofthemanual.
HighorLowPressure
Switchestrippedor
defective.
Checksystempressureandchargewithgauges.Replace
switchesifrequired.
Compressorand
evaporatorcycleon
andoff
Cyclingoffofloworhigh
pressureswitch.
Checksystempressureandchargewithgauges.Replace
switchesifrequired.