Bryant furnace error codes for the 310, 311 and 312 series
Bryant furnace codes are two-digit numbers flashed by the status LED on 310, 311 and 312 series furnaces: short flashes first, then long ones. The table below lists every Bryant furnace error code verified for these series with its meaning. Each row opens a page with the checks and the source document. The two unnumbered states, light off and rapid flashing, get rows of their own.
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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 |
|---|---|---|
| LED off | Bryant furnace 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 |
| rapid flashing | Bryant furnace 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 |
| 1 short + 1 long | Bryant furnace 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 |
| 1 short + 2 long | Bryant furnace 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 |
| 1 short + 3 long | Bryant furnace 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 |
| 1 short + 4 long | Bryant furnace 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 |
| 2 short + 1 long | Bryant furnace 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 |
| 2 short + 2 long | Bryant furnace 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 |
| 2 short + 3 long | Bryant furnace code 23: Pressure Switch Did Not Open Official: obstructed pressure tubing or a pressure switch stuck closed. | Bryant 310/311/312 series |
| 2 short + 4 long | Bryant furnace 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 |
| 3 short + 1 long | Bryant furnace 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 |
| 3 short + 3 long | Bryant furnace 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 |
| 3 short + 4 long | Bryant furnace 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 |
| 4 short + 5 long | Bryant furnace 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 |
Same control platform, other brand names: Carrier furnace codes · Payne furnace codes
Common questions about Bryant furnace codes
What does the blinking light on a Bryant furnace mean?
On the 310, 311 and 312 series it is flashing a two-digit code. Count the short flashes, then the long ones: the short count is the first digit and the long count is the second, so one short and four long is code 14. Look that pattern up in the table above. If the light is off, or blinking too fast to count, that is not a numbered code. No light means the board is not powered, and rapid flashing means reversed line-voltage polarity. Both states have their own rows.
Are Bryant furnace error codes the same as Carrier and Payne codes?
For these series, yes. Bryant 310, 311 and 312 furnaces use the Carrier 58STA/58STX control platform, so every code on this page comes from the Carrier installation and service instructions for that control. The same list appears under Carrier furnace codes and under Payne furnace codes. No separate Bryant service document is cited. Check the code map against the label inside your blower door before you rely on a meaning.
Does this list cover every Bryant furnace?
No. It covers the status LED codes verified for the 310, 311 and 312 series. Bryant furnaces built on Carrier's two-stage variable-speed or modulating controls use different code lists, which this site has not verified against a Bryant document. If your series is not listed, go by the code legend on the label inside the blower door rather than this table.
Will a Bryant furnace code clear on its own?
Some do. Lockout codes 13 and 14 reset on their own after 3 hours and code 45 after 1 hour, while code 21 does not auto-reset. The control also erases its stored code after 72 hours, so a technician who arrives later may find nothing to recall. Write the pattern down while it is showing.
Not sure how to read the light?
Use the interactive blink decoder — tap the pattern you see and we'll match it.
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