Payne Furnace Code 23.3
WarningShown as: Major code 23 flashed on the LED (2 short, 3 long); 23.3 on the display
Over pressure at start-up. The pressure transducer output is above 0.65 Vdc at the start of the heating sequence, so the control delays ignition until the signal returns to range.
Manual wording: “23.3 OVER PRESSUREAT START-UP - Voltage output from transducer is > 0.65 Vdc at start of heating sequence.”
Documented for: PG80MSU
Likely causes, most common first
- Improper vent sizing
- Obstruction in the pressure tubing
- Defective transducer
- Defective transducer wiring
- Excessive wind
What you can safely check yourself
- Check outdoor intake and exhaust terminations for snow, ice, or debris
When to call a technician
The pressure transducer and its tubing are inside the furnace cabinet - have a technician test them.
A Payne furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.
Source
- PG80MSU: Installation, Start-up, Operating and Service and Maintenance Instructions (Payne, PG80MSU 80% multipoise gas furnace with 3-digit display and pressure transducer) · checked 2026-08-25