Bryant furnace error codes

Blower on after power-up. The blower runs for 90 seconds if the furnace is powered up during a call for heat, or if that call opens during the blower on-delay. The same guide's sequence says the amber LED flashes 12 during those 90 seconds, then stays on continuously if no fault is found.

Limit circuit lockout. The limit or flame rollout switch was open longer than 3 minutes, or 10 successive limit trips occurred during high heat. The control auto-resets after 3 hours. The manual says to see status code 33.

Ignition lockout. The system failed to ignite gas and prove flame in 4 attempts. The control auto-resets after 3 hours. The manual says to see status code 34.

Blower motor lockout. The blower failed to reach 250 RPM, or failed to communicate, within 30 seconds after being turned on, in two successive heating cycles. The control auto-resets after 3 hours. The chart says to see status code 41.

Gas heating lockout. The control will not auto-reset. The chart says to check for a mis-wired gas valve or a defective control valve relay.

Abnormal flame-proving signal. Flame is proved while the gas valve is de-energized. The inducer runs until the fault clears. The chart says to check for a leaky gas valve or a stuck-open gas valve.

Pressure switch did not open. The chart says to check for obstructed pressure tubing or a pressure switch stuck closed.

Secondary voltage fuse is open. The chart says to check for a short circuit in the secondary (24 V) wiring.

Model selection or setup error. The model plug PL4 is missing or incorrect, or setup switch SW1-1 or SW1-6 is in the wrong position. If 25 flashes only four times at power-up, the control is using the model stored in memory.

High-heat pressure switch or relay did not close, or it reopened. The chart says the control relay may be defective or the gas valve may be mis-wired, and it says to see status code 32.

Low-heat pressure switch did not close, or it reopened. If it stays open longer than five minutes, the inducer shuts off for 15 minutes before a retry. If it opens during the blower on-delay, the blower comes on for the selected blower off-delay.

Limit circuit fault. A limit, draft safeguard, flame rollout, or blocked-vent switch is open, or the furnace is in high-heat only after two successive low-heat limit trips. The blower runs for 4 minutes or until the switch remakes, whichever is longer. Open longer than 3 minutes becomes lockout 13.

Ignition proving failure. The control tries three more times before lockout 14. If the flame signal is lost during the blower on-delay, the blower runs the selected off-delay.

Gas valve fault on a Bryant 987MA modulating furnace. The modulating gas valve failed to respond to a command from the furnace control, or power to the gas valve electronics was interrupted.

Blower motor fault. The blower failed to reach 250 RPM, or failed to communicate, within 30 seconds after being turned on or within 10 seconds during steady-state operation.

Inducer motor fault on a Bryant 987MA modulating furnace. The inducer has not started within 20 seconds after a call for heat, the inducer RPM is outside its valid range, or the RPM signal was lost for 5 seconds during operation.

Low-heat pressure switch is open while the high-heat pressure switch is closed. The chart says to check the pressure tubing, low inlet gas pressure if a low-gas-pressure switch is used, mis-wired switches, and a low-heat switch stuck open.

Line voltage polarity is reversed, or, on twinned furnaces, the transformers are out of phase. The status table states the polarity fault. The rapid-flashing section is the twinning case.

Control circuitry lockout. The control auto-resets after a 1-hour lockout caused by a flame-sense circuit failure, a gas-valve relay stuck open, or a software check error. Reset power to clear the lockout. Replace the control if the code repeats.