Applicable Systems
Carrier ComfortLink Thermostat/Controller
Symptoms
Oil return fault. The compressor oil return system is not operating correctly.
Possible Causes
- Oil return line restricted or clogged
- Oil return solenoid valve failure
Troubleshooting Steps
- Step 1: Check the oil return line for restrictions
Line is clogged or restricted - Step 2: Test the oil return solenoid valve operation
Valve is not opening
How to Reset
To reset: Fix the oil return line or valve, then reset the controller.
Source: Carrier HVAC Troubleshooting Guide, Carrier Corporation
Category: HVAC Residential