Applicable Systems
Copeland Scroll Compressor (CoreSense/Comfort Alert)
Symptoms
The compressor reports a system low-pressure switch trip. The low-pressure safety switch has activated, cutting power to protect the compressor from low suction conditions.
Possible Causes
- Refrigerant leak causing low system charge
- Evaporator load too low for the compressor capacity
- Expansion valve stuck closed or capillary tube blocked
Troubleshooting Steps
- Step 1: Perform a thorough leak inspection of all joints and fittings
Leaks are found and repaired - Step 2: Verify the evaporator heat load is sufficient for the compressor
Load matches the compressor capacity range - Step 3: Check expansion valve bulb attachment and superheat setting
Valve operates correctly with proper superheat
How to Reset
To reset: Raise suction pressure above the threshold, then reset the low-pressure switch.
Source: Copeland Scroll Compressor Service Manual, Emerson Climate Technologies
Category: Refrigeration