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8 Basic test procedure
8.1 Defective compressor
Compressors are single phase, depending on the model unit. All compressor motors are permanent
split capacitor type using only a running capacitor across the start and run terminal.
All compressors are internally spring mounted and externally mounted on rubber isolators.
8.1.1 Compressor wiring test
Remove compressor terminal box cover and disconnect wires from terminals. Using an
ohmmeter, check continuity across the following:
Terminal "C" and "S" - no continuity
- Open winding - replace compressor.
Terminal "C" and "R" - no continuity
- Open winding - replace compressor.
Terminal "R" and "S" - no continuity
- Open winding - replace compressor.
8.1.2 Ground test
Use an ohmmeter to set on its highest scale. Touch one lead to the compressor body (clean point of
contact as a good connection is a must) and the other probe in turn to each compressor terminal (see
Figure 2.) If a reading is obtained, the compressor is grounded and must be replaced.
8.1.3 Checking the compressor efficiency
The reason for compressor inefficiency is normally due to broken or damaged suction and/or
