Troubleshooting Checklist for Domestic Refrigerators and Freezers (Continued)
What to look for and what to do
5. Unit does not run and tempera-
No power at outlet
Check the fuses, and replace burned-out ones.
ture is too high
Poor plug contact
Spread the plug contacts.
Control in "Off" position
Turn to the "Coldest" position, then back to the Normal position
Examine the control main contacts; clean them with a magneto file or
with fine sandpaper; replace them if they are badly burned or pitted.
Do not use emery cloth. Check and replace the relay assembly, if
necessary. If the temperature control main contacts are found open,
try warming the temperature control bulb by hand. If this does not
close the control contacts, the control bellows has lost its charge, and
the control should be replaced.
Pressures in system not
Wait for a period of about 5 minutes before trying to restart the unit.
See item 3.
Open circuit in wiring
Make voltmeter or test-lamp checks to determine whether any part of
the electrical wiring system is open, or any controls are inoperative.
Correct defective connections, and replace worn or damaged controls
Compressor thermostat open
See item 1.
Open motor windings
See item 1.
6. Unit runs for short periods;
On a unit equipped with a defrosting heater, check the defrosting
temperature too high
cycle in accordance with the manufacturers instructions. Ascertain
whether the defrosting heater is turned off by making sure that no
current flows through it during the refrigerating cycle.
Unit operates on
See item 9.
7. Unit runs continuously; tempera-
Moisture, obstruction, or
Before checking for moisture, be certain that the symptoms observed
ture too high
restriction in liquid line
are not caused by improper operation of the defrosting heater, if so
equipped. These heaters are wired into the cabinet wiring so that the
control contacts short out the heaters when the contacts are closed.
Thus the heaters are on only when the machine is off, when the
control contacts open, and when the evaporator is on the defrost
cycle. Check the control contacts to see that the defrosting heaters are
off when the machine is running. At high ambient temperature, the
unit will cycle on its thermostat. The evaporator will warm up over its
entire surface is the liquid circulation is completely obstructed. If it is
only partly obstructed, a part of the frost on the evaporator will melt.
Under these conditions, the unit will probably operate noisily, and the
motor will tend to draw a heavy current. If the liquid line is obstructed
by ice, this ice will melt after the unit has warmed up. The unit will
then refrigerate normally. If this obstruction occurs too frequently
and spare units are available, replace the unit.
Exceedingly high current to the motor. No cooling in the evaporator
and no heating in the condenser. Excessive compressor noise.
Replace the hermetic compressor or replace the valves in an
Check the tubing for damage, sharp bends, kinks, pinches, etc.
Straighten the tubing, if possible, or replace the unit.