Error code reference

Carrier Furnace Error Codes

14 error codes documented with diagnostic procedures.

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11No previous code stored; stored status codes are erased when power (115VAC or 24VAC) to…12Blower runs for 90 seconds after power up if unit is powered up during a call for heat…13Limit circuit lockout occurs if the limit, draft safeguard, flame rollout, or blocked…14Ignition lockout; system failed to ignite gas and prove flame in 4 attempts; control will…21Gas heating lockout; control will NOT auto-reset.22Abnormal flame-proving signal; flame is proved while gas valve is de-energized 23Pressure switch did not open.24Secondary voltage (24VAC) fuse is open.31Pressure switch did not close or reopened; if open longer than 5 minutes, inducer shuts…32Low-heat pressure, draft safeguard (when used), or auxiliary limit switch (downflow only)…33Limit circuit fault; indicates a limit, draft safeguard, flame rollout, or blocked vent…34Ignition proving failure; if flame is not sensed during the trial for ignition period…43Low-heat pressure, draft safeguard (when used), or auxiliary limit switch (when used)…45Control circuitry lockout; auto-reset after one hour due to gas valve relay stuck open…

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