Bryant Furnace Code 23.1
WarningShown as: 2 short flashes, 3 long flashes
Stuck-closed main pressure switch. The control expected the main (low-heat) pressure switch to be open before the inducer started, and it was already closed.
Manual wording: “23 1 Stuck closed Main pressure switch”
Documented for: 912SE, 926TC
Likely causes, most common first
- Obstructed pressure tube
- Pressure switch stuck closed
When to call a technician
The pressure switch is a combustion safety device. A technician has to inspect the tube and switch. Never jumper or bypass a pressure switch.
A Bryant furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.
Sources
- Installation, Start-up, Operating and Service and Maintenance Instructions - 912SE (Bryant Heating & Cooling Systems, 912SE Legacy Line 92% single-stage condensing gas furnace) · checked 2026-08-25
- Installation, Start-up, Operating and Service and Maintenance Instructions - 926TC (Bryant Heating & Cooling Systems, 926TC Preferred Series two-stage, variable-speed ECM multipoise condensing gas furnace) · checked 2026-08-25