Bryant furnace error codes
For Bryant 310, 311 and 312 series furnaces, count the short and long flashes in one sequence. The table links each pattern to its meaning, checks and source document.
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How to read Bryant flash codes
Short flashes are the tens digit and long flashes are the units, so one short flash followed by four long flashes is code 14. Rapid flashing and a dark LED are separate conditions. Watch the full sequence at least once before writing the code down.
What this Bryant page covers
These Bryant series use a Carrier control platform, so the definitions come from Carrier source documents for that shared status LED. They apply only to the Bryant 310, 311, and 312 series listed here. Carrier's two-stage variable-speed and modulating code families are not included on this page.
- Status LED — short + long flash codes: Bryant 310/311/312 series
Bryant flash code quick reference
| Code or flash pattern | Meaning | Model family | Details |
|---|---|---|---|
| LED off | Status LED Off — No Power Official: check for 115VAC at L1/L2 and 24VAC at SEC-1/SEC-2. No light means the board isn't powered. | Bryant 310/311/312 series | View details |
| rapid flashing | Rapid Flashing — Reversed 115V Polarity Official: line-voltage polarity is reversed — and the control blocks heating until it's fixed. (If the furnace is twinned, see the twinning-kit instructions.) | Bryant 310/311/312 series | View details |
| 1 short + 1 long | Code 11 — No Previous Fault Stored 1 short + 1 long flash on recall = nothing stored. Codes self-erase after 72 hours (and on RED-LED boards, whenever power is interrupted). | Bryant 310/311/312 series | View details |
| 1 short + 2 long | Code 12 — Blower-On After Power-Up The furnace was powered up in the middle of a call for heat (R-W closed), so the blower runs 90 seconds first. Informational, not a fault. | Bryant 310/311/312 series | View details |
| 1 short + 3 long | Code 13 — Limit Circuit Lockout A limit, draft safeguard, flame rollout, or blocked-vent switch stayed open longer than 3 minutes → lockout. Auto-resets after 3 hours. Root causes = see code 33. | Bryant 310/311/312 series | View details |
| 1 short + 4 long | Code 14 — Ignition Lockout The system failed to ignite and prove flame in 4 attempts. Auto-resets after 3 hours. Root causes = see code 34. | Bryant 310/311/312 series | View details |
| 2 short + 1 long | Code 21 — Gas Heating Lockout (No Auto-Reset) Official: mis-wired gas valve, a stuck-closed gas-valve relay on the control, or a shorted gas-valve wire. This one does NOT auto-reset. | Bryant 310/311/312 series | View details |
| 2 short + 2 long | Code 22 — Abnormal Flame-Proving Signal Flame is proved while the gas valve is de-energized; the inducer runs until the fault clears. Official causes: a leaky or stuck-open gas valve. | Bryant 310/311/312 series | View details |
| 2 short + 3 long | Code 23 — Pressure Switch Did Not Open Official: obstructed pressure tubing or a pressure switch stuck closed. | Bryant 310/311/312 series | View details |
| 2 short + 4 long | Code 24 — Secondary Voltage Fuse Open A short in the 24VAC wiring blew the board's automotive-type 3-amp fuse. Official: replace with a 3-amp fuse ONLY. | Bryant 310/311/312 series | View details |
| 3 short + 1 long | Code 31 — Pressure Switch Did Not Close or Reopened If the switch stays open over 5 minutes, the inducer rests 15 minutes and retries. Official checklist: excessive wind, low inlet gas pressure (if LGPS used), disconnected or obstructed pressure tubing, defective switch. | Bryant 310/311/312 series | View details |
| 3 short + 3 long | Code 33 — Limit Circuit Fault A limit, draft safeguard, flame rollout, or blocked-vent switch is open. The blower runs 4 minutes or until it closes; open >3 minutes escalates to lockout code 13. Rollout and BVSS switches need a manual reset. | Bryant 310/311/312 series | View details |
| 3 short + 4 long | Code 34 — Ignition Proving Failure No flame proved during the trial for ignition; the control retries 3 more times before lockout 14. Official checklist: flame sensor must not be grounded, oxide buildup (clean with fine steel wool), proper microamps (0.5 min, 4.0–6.0 nominal), gas valve on, igniter health, inlet gas pressure. | Bryant 310/311/312 series | View details |
| 4 short + 5 long | Code 45 — Control Circuitry Lockout Auto-resets after 1 hour. Official causes: gas-valve relay stuck open, flame-sense circuit failure, or a software check error. Reset power to clear; replace the control if it repeats. | Bryant 310/311/312 series | View details |
Same control platform, other brand names: Carrier furnace codes · Payne furnace codes
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