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Component Testing
Component Description Test Procedures
Compressor When compressor electrical circuit is Resistance test
energized, the start winding current 1. Disconnect power to unit.
causes relay to heat. After an amount 2. Discharge capacitor by shorting across terminals with a
of starting time, start winding circuit resistor for 1 minute.
turns off. Relay will switch off start 3. Remove leads from compressor terminals.
winding circuit even though
compress- 4. Set ohmmeter to lowest scale.
or has not started (for example, when 5. Check for resistance between
attempting to restart after momentary Terminals “S” and “C”
power interruption). Terminals “R” and “C”
If either compressor winding reads open (infinite or very
high resistance) or dead short (0 ohms), replace
compressor.
With “open” relay, compressor will Ground Test
not start because there is little or no 1. Disconnect power to refrigerator.
current to start windings. Overload 2. Discharge capacitor be shorting terminals through a
protection will open due to high resistor for 1 minute.
locked rotor run winding current. 3. Remove compressor leads and use an ohmmeter set on
highest scale.
With “shorted” relay or capacitor, 4. Touch one lead to compressor body (clean point of
contact
compressor will start and overload and the other probe to each compressor terminal. If a
Protector will quickly open due to reading is obtained, compressor is grounded and must be
high current of combined run and Operation Test
start windings. If voltage, capacitor, overload, and motor winding test
good, perform the following test.
With open or weak capacitor, 1. Disconnect power to refrigerator using power switch.
compressor will start and run as 2. Discharge capacitor by shorting capacitor terminals
normal but will consume more through a resistor for 1 minute.
energy. 3. Remove leads from compressor terminals.
4. Wire a test cord to power switch.
5. Place time delayed fuse with UL rating equal to amp
rating of motor in test cord socket.
6. Remove overload and relay.
7. Connect start, common and run leads of test cord on
appropriate terminals of compressor.
8. Attach capacitor leads of test cord together. If
capacitor is used, attach capacitor to a known good
capacitor of