Applicable Systems
Carrier ComfortLink Thermostat/Controller
Symptoms
Voltage abnormal fault. The supply voltage is outside the normal operating range.
Possible Causes
- Power supply voltage too high or too low
- Voltage imbalance in three-phase supply
Troubleshooting Steps
- Step 1: Check the supply voltage at the unit
Voltage is outside the rated range - Step 2: Install or adjust a voltage regulator
Voltage is stabilized within range
How to Reset
To reset: Restore the voltage to within range, then reset the controller.
Source: Carrier HVAC Troubleshooting Guide, Carrier Corporation
Category: HVAC Residential