Carrier Error Code 31: High Stage Pressure Fault
How to Fix Carrier Code 31
- Step 1: Turn off the HVAC system at the thermostat.
- Step 2: Inspect the outdoor unit for any obvious obstructions, such as leaves, debris, or snow, blocking airflow to the condenser coil. Clear away any obstructions.
- Step 3: Wait 30 minutes, then turn the system back on at the thermostat. If the error code reappears, contact a qualified HVAC technician for further diagnosis and repair.
How to Reset Carrier Code 31
- Turn off the furnace power switch, usually located on or near the unit.
- Turn off the circuit breaker for the furnace. Wait 30 seconds.
- Restore power at the breaker and flip the furnace switch back on.
- Set the thermostat to call for heat. If the error code returns after 2-3 ignition attempts, the fault requires repair.
What does 31 mean?
The Carrier error code 31, or a blinking LED pattern indicating code 31, signals that the system's high-pressure switch has tripped during high-stage operation. This switch is a safety device designed to shut down the compressor when the refrigerant pressure gets too high, preventing damage to the compressor and other components. The high-stage refers to when the unit is operating at its maximum cooling or heating capacity.
This error usually means there's a restriction in the refrigerant flow, a problem with the compressor, or an issue with the outdoor fan motor. It's important to address this issue promptly to prevent further damage to your HVAC system. Because this code indicates a locked-out system, you will likely need a professional to diagnose and fix the root cause.
Affected Models
- Performance Series Furnace
- Comfort Series Furnace
- Infinity Series Furnace
- Performance Series
- Base Series Furnace
- Performance Boost Furnace
- Performance Boost 95 Furnace
- WeatherMaker 8000
- WeatherMaker 9300
- Infinity 80
- WeatherMaker Furnace
- 24ABC6 Air Conditioner
- 25HBC5 Heat Pump
- Performance Series Heat Pump
- Infinity Series
- Performance Series Heat Pump
- Base Series
- Performance Series
- Comfort Series
- Infinity Series Heat Pump
- Comfort Series Heat Pump
- Infinity 20 Heat Pump with Greenspeed Intelligence
- Comfort 80 Gas Furnace
Replacement Parts
| Part | OEM Number | Est. Cost |
|---|---|---|
| High-Pressure Switch | — | — |
| Outdoor Fan Motor | HC39GE230A | — |
| Condenser Coil | — | — |
Related Codes on Same Models
| Code | Description | Severity |
|---|---|---|
| 11 | No Previous Error | Info |
| 12 | Blower On After Power Up | Warning |
| 13 | Limit/Rollout Fault | Critical |
| 14 | Ignition Lockout | Critical |
| 21 | Gas Heating Lockout | Critical |
| 22 | Abnormal Flame | Critical |
| 23 | Pressure Switch Fault | Warning |
| 24 | Secondary Voltage Fuse | Warning |
| 32 | Low Flame Sense | Warning |
| 33 | Limit/Rollout Switch Lockout | Critical |