Payne PG80ESA Error Code 31: Pressure Switch Did Not Close or Reopened
What Does Code 31 Mean?
Status code 31 on the Payne PG80ESA indicates that the pressure switch did not close or reopened during operation. The pressure switch is a safety device that verifies the inducer motor is creating enough draft to safely vent combustion gases out of your home.
When the pressure switch stays open for longer than 5 minutes, the inducer shuts off for 15 minutes before retrying. If the pressure switch opens during the blower on-delay period, the blower will come on for the selected blower off-delay time. This is the furnace's way of protecting itself and your home from potentially dangerous exhaust gas buildup.
The most common cause is a blocked or restricted exhaust vent pipe. Since the PG80ESA is a non-condensing (80% AFUE) furnace, it typically vents through a metal flue pipe. Snow, ice, debris, bird nests, or insect nests can block the vent where it exits through the roof or wall. Disconnected or obstructed pressure tubing between the inducer and the pressure switch is another common cause. Excessive wind, a defective inducer motor, low inducer voltage, a defective pressure switch, or inadequate combustion air supply are also possible causes.
Common Causes
When to Call a Professional
Contact a licensed HVAC technician if:
- The exhaust vent appears clear but code 31 persists
- The inducer motor sounds unusually loud, rattles, or does not start
- You cannot safely access the vent termination to check for blockages
- The code occurs primarily on windy days (may indicate improper vent termination)
- You notice disconnected or damaged pressure switch tubing
Sources
✓ Verified against manufacturer service manual — March 2026