ICP fault codes

Drive is enabled but stays at min Hz or 0 because analog / serial speed is missing.

1 plate

Example on most Carrier/Bryant packaged CES IGC stickers: pressure switch / draft did not make. Confirm the sticker in THIS heat section — revisions differ.

1 plate

Example on many CES rooftop IGC stickers: limit open. Confirm THIS sticker.

1 plate

Example: rollout / aux limit on many CES stickers; consecutive limit on others. Read THIS IGC.

1 plate

Example on many CES rooftop IGCs: ignition lockout after retries. Confirm THIS sticker.

1 plate

Example: internal control / valve circuit on current CES rooftop stickers. Power-cycle once; if 8-flash returns, valve ohms then IGC.

1 plate

Memory empty or power was cycled.

3 plates

Powered up on a W call — blower runs ~90 s.

3 plates

Limit/rollout stayed open. Auto-reset ~3 h. Hardened 33.

3 plates

Hardened 34. Auto-reset ~3 h.

3 plates

Flame sense while the gas valve is de-energized.

3 plates

24 V fuse on the IFC.

3 plates

Inducer running, the one PS did not close (or the draft path will not hold). On this 96% that is trap / PVC / inducer.

3 plates

The winter callback. Airflow first; rollout is hazard.

3 plates

Trial without flame sense. Repeats → 14.

3 plates

JADE LCD: ACT ERROR / ACT RANGE. Actuator did not follow command. Feedback pot off the shaft is the weekly.

1 plate

HERM and/or FAN section out of rating. Single-stage Comfort dies this way all summer.

4 plates

Wrong charge method is as common as wrong charge.

4 plates

JADE LCD: CO2 / SENS ERR. DCV sensor failed or the 0–10 V input is floating. Damper holds open; compressor never runs.

1 plate

Will not pull, chatters, or is welded.

5 plates

Float switch or tripped condensate opened 24V.

1 plate

Start here when the hood is the complaint. Title 24 FDD classes: sensor, not-economizing, false-economizing, damper not modulating, excess OA.

1 plate

Drive has line voltage but will not run — the unit board never enabled it.

1 plate

Damper open past the commanded minimum with no economizer or DCV request.

1 plate

Damper open with OA above changeover. Space hot, high OA bills, or wet coil.

1 plate

Controller did not see blower current / pressure.

1 plate

Flame present then dropped, or µA too low to prove.

1 plate

JADE LCD: FREEZING. Mixed air below the low-limit. Damper drives shut; mechanical cool may lock.

1 plate

Keypad example: GF. Drive sees current to ground on the motor leads.

1 plate

Outdoor HPS opened — coil circuit is dead. Not an inverter pressure fault and not an L-code.

5 plates

Trial for ignition failed after the IGC retries.

1 plate

No 24V at the ignition control, or the module is dead.

1 plate

Heat-exchanger or supply limit opened.

1 plate

Drive is running too slow to close the prove switch, so the unit board reports fan fail. Reliatel example: Fan Fail with the drive still at min Hz.

1 plate

Suction dropped out the low-pressure switch.

1 plate

JADE two-line LCD: MA / SENS ERR. Mixed-air sensor failed. This one alarms immediately on power-up — others wait the 60-minute setup window.

1 plate

Damper is two-position (0 or 100) instead of tracking 2–10 V. Title 24 FDD class.

1 plate

OA is in the free-cooling window and the damper stayed shut. Title 24 FDD class.

1 plate

JADE LCD: OA / SENS ERR (or OA SYLK ERR). Outside-air thermistor failed or lost SYLK. Board thinks the roof is 20 °F or 120 °F.

1 plate

Keypad example: oC (Yaskawa) or OC. Output current trip. Locked rotor, dirty filters, or FLA set too low.

1 plate

Fan not turning. Compressor may still run and then HPS.

4 plates

Keypad example: oH. Drive thermal trip.

1 plate

Keypad example: ov (Yaskawa) or OU. DC bus high. Usually regen on decel, not a new drive.

1 plate

Keypad example: PF. Missing or imbalanced incoming phase.

1 plate

Three-phase monitor opened.

1 plate

Inducer ran (or should have) and the draft switch did not make.

1 plate

JADE LCD: RA / SENS ERR. Return-air thermistor failed. Differential / enthalpy changeover compares OA to RA.

1 plate

Flame left the burner box.

1 plate

Supply or return smoke detector, or a firestat, has the unit locked out.

1 plate

Flame with no trial.

1 plate

Keypad example: Uv (Yaskawa) or LU. DC bus dropped. Incoming power or a missing phase.

1 plate

The indoor fan is a drive, not a contactor + cap. Type the keypad string: oC, Uv, ov, GF, oH, PF.

1 plate