25
2005 Boreal Geothermal Inc.
www.boreal-geothermal.com
BOREAL
® ACDX Heat Pump Trouble Shooting Guide
Fault
Possible Cause
Verification
Recommended Action
Compressor not
operating
Power Failure
Electric circuit test shows no voltage
on the line side of compressor con-
tactor.
Check for blown fuse at heat pump’s
disconnect box or blown fuse
Disconnect switch open
Voltmeter shows no voltage on the
line side of the compressor contactor.
Determine why the disconnect
switch was opened, if all is OK close
the switch.
Fuse blown
At heat pump disconnect box, volt-
meter shows voltage on the line side
but not on the load side.
Replace fuse with proper size and
type. (Time-delay) type “D”
Check total load on system.
Low voltage
Voltmeter shows abnormally low
voltage (Below 210 v) at heat pump
disconnect switch.
Call power company.
Burned out motor
Ohmmeter shows no resistance be-
tween common and run terminals or
between common and start terminals.
Note: Be sure compressor overload
has had a chance to reset. If comp. is
hot this may take several hours.
Determine cause and replace motor.
Thermal overload on com-
pressor tripped.
Ohmmeter shows reading when
placed across R and S terminals and
infinity between C & R or C & S.
Make sure the internal overload has
had time to reset.
If windings are open or overload is
faulty, replace compressor.
Faulty compressor contactor. Voltage on line side with contactor
held closed, but no voltage on one or
both terminals on the load side.
Points pitted or burned.
Replace contactor.
Seized compressor due to
locked or damaged mecha-
nism.
Compressor attempts to start but
trips it’s internal overload after a few
seconds.
Attempt to “rock” compressor free.
If normal operation cannot be estab-
lished, replace compressor.
Faulty run capacitor.
Check with ohmmeter for shorts,
open etc.
Replace if faulty.
