The counting trips everyone up the first time: a Carrier code is two numbers. Count the short flashes — that is the first digit. Count the long flashes — that is the second. Code 33, the most-searched furnace code there is, is three short and three long. If you counted "six blinks," you were looking at a 33.
The board also remembers. Stored codes can be recalled without cutting power (Carrier’s manual warns that removing power or the blower door erases them), and a fault that sits long enough escalates: an open limit is code 33, but leave it open past three minutes and the board files it as lockout code 13.
The two rules that outrank everything on this page.
1. Smell gas? Stop reading. Leave the house and call your gas utility or 911 from outside. No code is worth diagnosing through a gas smell.
2. Never bypass a safety switch — no jumping a pressure switch, no taping a limit, no propping a rollout. Those switches are the only thing between a furnace fault and a fire or carbon-monoxide problem. This library explains codes; it does not teach repairs inside the cabinet.
Which chart is yours?
This chart covers the Carrier control used across the 58-series induced-combustion furnaces and the matching Bryant and Payne models — the one with the single status LED beside the blower compartment. Newer Infinity/Evolution systems with full text displays use an expanded code set (the 41-45 blower codes and friends) that is not in this table, because we have not transcribed that manual yet.
Two-digit status codes — short flashes, then long flashes
Carrier 58-series and their Bryant/Payne twins. First digit = number of short flashes; second digit = number of long flashes. Code 33 is 3 short, pause, 3 long.
| What you see | What the manual says it means |
|---|---|
| LED off (continuous) | No power at the control — The manual’s check: 115VAC at L1 and L2, 24VAC at SEC-1 and SEC-2. In plain terms, the board is not being fed — start at the switch and the breaker. |
| LED on (continuous) | Control has 24VAC power — Listed because homeowners search it: a steady light on this board is health, not a fault. |
| Rapid flashing | Line voltage (115VAC) polarity reversed — Hot and neutral are swapped at the furnace. If the unit is twinned, the manual sends you to the twinning kit instructions instead. |
| Code 11 | No previous code — Stored codes were erased — power to the control was interrupted, or 48 hours passed after the last fault cleared. An 11 means the memory is empty, not that something is broken. |
| Code 12 | Blower on after power-up — If power comes back during a call for heat, the blower runs 90 seconds. That is the design, not a malfunction. |
| Code 13 | Limit or flame roll-out switch lockout — The lockout version of code 33. The control auto-resets after three hours; the flame roll-out switch itself needs a manual reset. Read code 33 for the cause list. Full page → |
| Code 14 | Ignition lockout — The lockout version of code 34 — the furnace tried, failed to prove ignition, and shut down. Auto-resets after three hours. Full page → |
| Code 21 | Gas heating lockout — will NOT auto-reset — The manual’s check list is short and serious: mis-wired gas valve, or a defective control (valve relay). No homeowner step here. Full page → |
| Code 22 | Abnormal flame-proving signal — Flame is proved while the gas valve is de-energized, and the inducer will run until the fault clears. Manual check-for: a leaky or stuck-open gas valve. |
| Code 23 | Pressure switch did not open — Before each cycle the board confirms this switch is open. Manual check-for: obstructed pressure tubing, or the switch stuck closed. Full page → |
| Code 24 | Secondary voltage fuse is open — The little fuse on the board blew. The manual tells you why to care: check for a short circuit in the 24VAC wiring — a fuse that blows twice is a symptom, not the disease. Full page → |
| Code 31 | Pressure / draft safeguard / aux-limit switch did not close, or reopened — The big venting code on this family. Manual list: vent sizing, restricted vent, weak or dead inducer motor, bad pressure switch, excessive wind, disconnected or blocked pressure tubing, inadequate combustion air. If it opens after ignition, you get a 90-second recycle delay; open past five minutes and the inducer rests 15 minutes. Full page → |
| Code 32 | Pressure switch or relay did not close, or reopened — From Carrier’s 48XL manual: if the switch stays open longer than five minutes the inducer shuts off for 15 minutes before retrying. Same venting family as 31 — check the manual for your exact model to see which of the two your board uses. |
| Code 33 | Limit or flame roll-out switch is open — The most-searched Carrier code, and the manual is specific: dirty filter or restricted ducts, loose blower wheel, defective blower motor or capacitor, bad switch or connections — or the flame roll-out switch open, which needs a manual reset and a reason. Open longer than 3 minutes and the code becomes 13. Full page → |
| Code 34 | Ignition proving failure — The furnace lit (or tried to) and could not prove flame; it retries three more times before lockout 14. Manual check-for: oxide buildup on the flame sensor, a shut manual gas valve, low inlet gas pressure, a dead hot-surface ignitor, a defective gas valve, ground continuity. Full page → |
Source: Carrier 58YAV Service section - status code table. Read the document (fetched 2026-10-30).
One honesty note before the tables: codes change between control boards, sometimes inside the same brand and the same decade. Every table below names the board and the manual it was transcribed from. The chart glued inside your own blower door is the final word for your furnace — if it disagrees with this page, believe the door.
Questions
Are Bryant and Payne codes really the same as Carrier?
For furnaces built on this control, yes — the three brands share the platform and the status-code list in the service literature is the same. Model generations still matter, which is why the table names the document it came from.
What is the difference between code 33 and code 13?
Time. Code 33 is a limit or roll-out switch open right now. If it stays open longer than three minutes, the control escalates it to code 13, the lockout version, and starts the three-hour reset clock.
Where these meanings come from
Transcribed 2026-10-30 from the manufacturers’ own documents — not from other blogs:
- Carrier 58YAV Service section - status code table — read it