Service Manual 35
Troubleshooting Guide
COMPLAINT
CAUSE
REMEDY
Check the TEMP control. If not at the lowest number,
set TEMP control to this setting and restart the unit.
Check the continuity of the thermistor. Replace the
thermistor if the circuit is open.
Check the capacitor.
Replace if not within ±10% of manufacturers rating.
Replace if shorted, open, or damaged.
Check the compressor for open circuit or ground. If
open or grounded, replace the compressor.
Check the compressor overload, if externally mount-
ed. Replace if open. (If the compressor temperature
is high, remove the overload, cool it, and retest.)
Check the voltage.
If not within limits, call an electrician.
Check overload, if externally mounted.
Replace if open. (If the compressor temperature is
high, remove the overload, cool, and retest.)
If not running, determine the cause. Replace if
required.
Remove the cabinet. inspect the interior surface of
the condenser; if restricted, clean carefully with a vac-
uum cleaner (do not damage fins) or brush. Clean the
interior base before reassembling.
If condenser fins are closed over a large area on the
coil surface, head pressures will increase, causing
the compressor to overload. Straighten the fins or
replace the coil.
Test capacitor.
Check the terminals. If loose, repair or replace.
Check the system for a restriction.
If restricted, clean of replace.
Close if open.
Determine if the unit is properly sized for the area to
be cooled.
Check the set screw or clamp. If loose or missing,
correct. If the turbo or fan is hitting air guide,
rearrange the air handling parts.
Remove the cabinet carefully and rearrange tubing
not to contact cabinet, compressor, shroud, and barri-
er.
Thermistor
Capacitor (Discharge
capacitor before servicing.)
Compressor
Overload
Voltage
Overload
Fan motor
Condenser air flow restric-
tion
Condenser fins (damaged)
Capacitor
Wiring
Refrigerating system
Air filter
Exhaust damper door
Unit undersized
Turbo or fan
Copper tubing
Compressor will not run,
but fan motor runs.
Compressor cycles on
overload.
Compressor cycles on
overload.
Compressor cycles on
overload.
Insufficient cooling or heat-
ing
Excessive noise
