Troubleshooting
Should a major problem develop, refer to the following information for possible cause and
corrective steps:
Neither fan nor compressor run:
1. The fuse may be blown or the circuit breaker is open. Check electrical circuits and motor
windings for shorts or grounds. Investigate for possible overloading. Replace fuse or reset
circuit breakers after fault is corrected.
2. Wires may be loose or broken. Replace or tighten.
3. Supply voltage may be faulty. Check thermostat for correct wiring and check 24 volt
transformer for burnout.
Fan operates but compressor does not:
1. Check capacitor.
2. Wires may be loose or broken. Replace or tighten.
3. The high pressure may have tripped due to:
a. fouled or plugged condenser.
b. lack of or no condenser water.
c. too warm condenser water.
d. not enough airflow over the coil due to dirty filters.
e. coil or fan motor failure.
4. The low temperature switch may have tripped due to:
a. fouled or plugged condenser.
b. lack of or no condenser water.
c. too warm condenser water.
d. not enough airflow over the coil due to dirty filters.
e. coil or fan motor failure.
5. Check thermostat setting, calibration and wiring.
6. The compressor overload protection is open. If the compressor dome is extremely hot, the
overload will not reset until cooled down. If the overload is external, replace it. If the overload
is internal, replace the compressor.
7. The internal winding of the compressor motor may be grounded to the compressor shell. If so,
replace the compressor .
8. The compressor winding may be open. Check continuity with ohmmeter. If the winding is
open, replace the compressor.
Compressor attempts to start but doesn't:
1. Check capacitor.
2. Check for defective compressor by making resistance check on winding.
3. Check run capacitor.
Compressor runs in short cycle:
1. Check thermostat mounting and location.
2. Check all relays, relaying and contacts.
3. Check run capacitor.
4. Check high pressure switch.
5. Check low temperature switch.
6. See if reversing valve has not fully shifted to either side.
Insufficient cooling or heating:
1. Check thermostat for improper location.
2. Airflow may be insufficient. Check and clean the filter.
3. The reversing valve may be defective, creating a bypass of refrigerant. If the unit will not heat,
check the reversing valve coil.
4. Check capillary tubes for possible restriction of refrigerant flow.
5. Check for restriction in water flow.
Insufficient water flow through condenser:
1. Check to see that valves are open all the way.
2. Check for air in lines.
