Error Code Code 31
Carrier 58MVP Error Code Code 31: High Pressure Switch Fault
TL;DR
Indicates the high pressure switch (HPS) is closed at call for heat, or in low heat, or fails to close after call, or opens in high heat. The fault behavior varies by heating stage: in low heat, the inducer continues running for 15 sec then the unit shuts off; in high heat, the unit remains running at low-heat speed or reduces to low-heat speed for selected off delay. Most likely cause: plugged condensate drain. Disclaimer
This article is for informational purposes only and does not guarantee the accuracy or completeness of the information provided. Always turn off power and gas supply before attempting any repairs. If you smell gas, leave immediately and call your gas company. Consult a licensed HVAC technician for diagnosis and repair. Any actions taken based on this information are at your own risk. What Does Code Code 31 Mean?
Indicates the high pressure switch (HPS) is closed at call for heat, or in low heat, or fails to close after call, or opens in high heat. The fault behavior varies by heating stage: in low heat, the inducer continues running for 15 sec then the unit shuts off; in high heat, the unit remains running at low-heat speed or reduces to low-heat speed for selected off delay.
Common Causes
When to Call a Professional
Contact a licensed HVAC technician if:
- Basic troubleshooting did not resolve the error
- You smell gas at any point during the process
- You are not comfortable working around gas lines or electrical components
- The unit needs a gas valve, control board, or motor replacement