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Carrier 58STA / 58STX Furnace Codes
Similar two-digit status codes are used on many Carrier, Bryant and Payne furnaces, but titles and causes vary by model. Check the service label on the blower door.
| Code | Meaning | What to check |
|---|---|---|
| 11 | No previous code. | |
| 12 | Blower on after power up (normal). | Blower runs for 90 seconds if the unit is powered up during a call for heat, or when R-W opens during the blower on-delay. |
| 13 | Limit circuit lockout. | The limit, draft safeguard, flame rollout or blocked vent switch (if used) stayed open longer than 3 minutes. Auto-resets after three hours. See code 33. How to fix → |
| 14 | Ignition lockout. | Auto-resets after three hours. See code 34. How to fix → |
| 21 | Gas heating lockout. The control will not auto reset. | Mis-wired gas valve, or a defective control (valve relay). |
| 22 | Abnormal flame-proving signal. | Flame is proved while the gas valve is de-energized; the inducer runs until it clears. Leaky or stuck-open gas valve. How to fix → |
| 23 | Pressure switch did not open. | Obstructed pressure tubing, or pressure switch stuck closed. How to fix → |
| 24 | Secondary voltage fuse is open. | Short circuit in the 24 VAC wiring. How to fix → |
| 31 | Pressure switch did not close or reopened. | Vent sizing or restriction, low inducer voltage, combustion air, low inlet gas pressure (if LGPS used), inducer motor, pressure switch, pressure tubing, wind. Open more than five minutes: inducer shuts off for 15 minutes before retrying. How to fix → |
| 33 | Limit circuit fault. | Limit, draft safeguard, flame rollout or blocked vent switch is open. Dirty filter or restricted ducts, loose blower wheel, blower motor or capacitor, vent sizing, combustion air. Rollout and blocked vent switches are manual reset. How to fix → |
| 34 | Ignition proving failure. | The control tries three more times before code 14. Clean the flame sensor (0.5 microamps DC minimum), gas valve and manual shut-off, igniter, ground continuity, inlet gas pressure, flame carryover. How to fix → |
| 45 | Control circuitry lockout. | Gas valve relay stuck open, flame sense circuit failure, or a software check error. Auto-resets after one hour. Reset power; replace the control if the code repeats. |
How to read the codes
- Two-digit codes: the first digit is the number of short flashes and the second the number of long flashes.
- Continuous off: check for 115 VAC at L1 and L2 and 24 VAC at SEC-1 and SEC-2. Continuous on: the control has 24 VAC power. Rapid flashing: line voltage polarity reversed (if twinned, see the twinning kit instructions).
- Code recall: briefly remove then reconnect one main limit wire. On red LED boards, don't remove power or the blower door first. Stored codes are erased after 72 hours.
Codes point to a circuit, not a part. Test before replacing anything, and never jumper a limit, rollout or pressure switch to keep a furnace running. Gas and line-voltage work is for trained technicians.
Source: Carrier 58STA/58STX Installation, Start-up, Operating and Service and Maintenance Instructions, Form 58ST-24SI, Fig. 45 Service Label (327596-101 Rev. B), p. 43. The "meaning" column follows the manufacturer's wording; "what to check" is our field summary. Always go by the label on the furnace you're working on.
Related
- How to read furnace LED flash codes
- Furnace pressure switch troubleshooting
- Flame sensor microamps and cleaning
Other brands
- Lennox Merit ML180UH (80% single-stage)
- Carrier 58CVA / 58CVX (80% variable-speed two-stage)
- Rheem / Ruud R96V / 96MDV (96% two-stage communicating)
- Goodman / Amana GR9S80 / GD9S80 (80% single-stage)
- Trane / American Standard S9X1 / S9X2 / S9B1 (96% condensing)
- Lennox SL280UHV (80% two-stage variable speed)
- Goodman / Amana / Daikin GM9S96 / GC9S96 / GM9S92 (96% and 92% condensing, single-stage)
- Carrier 59TP6C two-stage condensing with InteliSense (Performance series)
- Lennox G60DF / G60DFV (older two-stage SureLight boards 18M3401, 46M9901, 18M9901, 49M5901)
- Lennox G60UH / G60UHV (SureLight boards 100869 and 100870)
- Rheem / Ruud R801T Ultra Low NOx (14 ng/J) single-stage upflow/horizontal, constant-torque blower
- Rheem / Ruud 802V / 80MDV (80% two-stage communicating, ECM blower; model numbers (-)802V and (-)(-)80MDV)
- Trane / American Standard S8B1 / S8X1 / S8X2 (80% single-stage and two-stage)
- Goodman / Amana GMVC96 / GCVC96 (96% two-stage variable-speed, *MVC96*BA and *CVC96*BA)
- Goodman / Amana GMVS96 / AMVS96 U-revision (96% variable-speed with analog pressure sensor, model numbers GMVS96*U and AMVS96*U)
- Goodman / Amana GMVM96 / GCVM96 / AMVM96 / ACVM96 (96% modulating, model numbers *MVM96 and *CVM96)
- Rheem / Ruud R801T / 80MSX (80% single-stage, constant-torque blower; model numbers (-)801T and (-)(-)80MSX)
- Rheem / Ruud 802P / 80MDP (80% two-stage, model numbers (-)802P and (-)(-)80MDP)
- Rheem / Ruud 802T / 80MDT (80% two-stage with constant-torque blower, model numbers (-)802T and (-)(-)80MDT)
- Rheem / Ruud 801S / 801P / 80MSS / 80MSP (80% single-stage, model numbers (-)801S, (-)801P, (-)(-)80MSS and (-)(-)80MSP)
- Carrier 58SB0A / 58SB1A (single-stage, non-condensing)
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