Compressor Troubleshooting - Boreal W-Series Installation And Service Manual

Fault
Compressor will
Faulty control board.
not start
Faulty run capacitor.
(Single phase only)
Loose or faulty wiring.
Faulty compressor
contactor.
Thermal overload on
compressor tripped.
Burned out motor.
(open winding)
Burned out motor.
(shorted windings)
Motor shorted to ground.
Seized compressor due to
locked or damaged
mechanism.
Start capacitor faulty.
Compressor
starts hard (Single phase only)
Potential Relay faulty.
(Single phase only)
Compressor is "tight" due
to damaged mechanism.
Compressor Faulty Stage 2 module.
Stage 2 will not
activate
02 JULY 2009

COMPRESSOR TROUBLESHOOTING

Possible Cause
Measuring from C on the terminal
strip, verify there is voltage at Y,
HP1, HP2, LP1, LP2, and both flow
pins but no voltage present at CC.
Check value with capacitance meter.
Should match label on capacitor.
Compressor will hum while trying to
start and then trip its overload.
Check all compressor wiring, includ-
ing inside compressor electrical box.
Voltage on line side with contactor
held closed, but no voltage on one
or both terminals on the load side.
Points pitted or burned.
Or, 24VAC across coil but contactor
will not engage.
Ohmmeter shows reading when
placed across R and S terminals
and infinity between C & R or C & S.
A valid resistance reading is present
again after the compressor has
cooled down.
Remove wires from compressor.
Ohmmeter shows infinite resistance
between any two terminals Note: Be
sure compressor overload has had a
chance to reset. If compressor is hot
this may take several hours.
Remove wires from compressor.
Resistance between any two termi-
nals is below the specified value.
Remove wires from compressor.
Check for infinite resistance be-
tween each terminal and ground.
Compressor attempts to start but
trips its internal overload after a few
seconds. (Run capacitor already
verified)
Check with capacitance meter.
Check for black residue around
blowout hole on top of capacitor.
Replace with new one and verify
compressor starts properly.
Compressor attempts to start but
trips its internal overload after a few
seconds. Run capacitor has been
verified already.
Verify if 24VAC is present across
Y2 and C of the terminal strip.
Verification
Page 27
Recommended Action
Replace control board.
Replace if faulty.
Fix any loose connections. Re-
place any damaged wires.
Replace contactor.
Proceed to Operation Trouble-
shooting to determine the cause
of the thermal overload trip.
Replace the compressor.
Replace the compressor.
If any terminal to ground is not
infinite replace the compressor.
Attempt to "rock" compressor free.
If normal operation cannot be
established, replace compressor.
Replace if faulty.
Remove black residue in electrical
box if any.
Replace if faulty.
Attempt to "rock" compressor free.
If normal operation cannot be es-
tablished, replace compressor.
Replace module if signal is pre-
sent. Check wiring if signal is not
present.
Boreal Geothermal Inc.