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7. If ohm readings are out of range, replace relay.
8. Reverse this procedure to reassemble.
NOTE: When replacing leads to the PTC relay,
ensure that locking tabs snap into terminal.
Overload Protector
The overload protector is completely thermally operated.
It will open from excessive heat or current. Unlike prior
overloads, the internal bimetal is not self-heating, and is
not a part of the electrical circuit. The overload has a
small built-in coil heater that is in series with the
compressor start and run windings (See Figure C3).
To Check/Replace Overload Protector
1. Disconnect electrical supply to refrigerator.
2. Remove bale wire holding relay to compressor.
3. Remove relay assembly from compressor.
4. Use flat-bladed screwdriver to gently pry capacitor
from relay assembly.
5. Use small, flat-bladed screwdriver to disconnect
leads to relay assembly. (Note: On some models you
will have to remove bale wire and cover, to gain
access to relay and overload protector.)
6. Use ohmmeter to check resistance between tab
terminal and female pin terminal. Overload protector
should have less than 1 ohm of resistance at normal
room temperature.
7. If ohm readings are out of range, install new
Starter/Overload Assembly. (See Figure C2)
8. Reverse this procedure to reassemble.
NOTE: When replacing leads to the PTC Relay,
ensure the locking tabs snap back into the terminal.
Run Capacitor
The run capacitor has permanently attached terminals
which are connected to relay terminals 2 and 3.
NOTE: Some models are not equipped with a run
capacitor
To Check/Replace Run Capacitor
1. Disconnect electrical supply to refrigerator.
2. Remove bale wire holding relay to compressor.
2. Use small, flat-bladed screwdriver to disconnect
leads to relay assembly.
3. Use flat-bladed screwdriver and gently pry
capacitor from relay assembly.
4. Discharge capacitor by shorting across terminals
with 500K (1 watt) resistor for one minute.
5. Use ohmmeter set on the "Ohms times 1000"
scale (if available), to check resistance across
capacitor wire terminals.
•
Needle should jump towards zero ohms and
quickly move back to infinity.
•
If needle does not move, capacitor is open.
•
If needle reads constant value at or near zero
ohms, capacitor is shorted out.
•
If needle jumps toward zero and then moves
back to constant high resistance (not infinity),
capacitor has high resistance leak.
6. If ohm readings are out of range, replace capacitor.
7. Reverse procedures to reassemble.
Compressor Start Circuit
When the compressor circuit is first energized, the solid
state relay has low resistance (3-12 ohms), and both the
run and start windings are energized to start the
compressor. The run capacitor is being bypassed by the
relay, and it has a minor function during compressor
starting (See Figure C4).
Compressor Run Circuit
When the self-heating solid state relay has reached
sufficient temperature, it will abruptly change from low
resistance (3-12 ohms) to very high resistance (10-20K
ohms) and, in effect, switch off the start windings.
The relay no longer shunts the run capacitor. The run
capacitor is now in series with the start windings. The
only purpose of the run capacitor is to improve
compressor operating efficiency, which it does by
correcting the power factor of the compressor motor
(See Figure C5).
25
Figure C4
Figure C5
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