What It Means
Improper reading relationship between outdoor coil and outdoor air sensors.
Carrier Air Conditioner
Carrier Air Conditioner Error Code 56
Troubleshooting guide for the Carrier Air Conditioner system fault 56.
Possible Causes
- Out-of-calibration outdoor air or coil sensor.
- Shorted or crossed sensor wiring harness.
- Faulty thermistor sensor.
Not sure which one it is — or if it's none of these? Try ACLogics today.
Disclaimer: This information is for general reference. Error codes can vary by model and production year. Always refer to your machine's specific manual and the information printed on the unit itself.
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Full Diagnosis
Thermistors Out of Range. Improper relationship between coil sensor and outdoor air sensor.
All Recorded Causes
Ohm out both the outdoor coil sensor and outdoor air temperature sensor against their respective charts. Check all sensor wiring for shorts or crossed connections. Replace whichever sensor is out of specification.
Verify Before Replacing Parts
- Confirm the exact Carrier model family and air conditioners context before acting on a generic code description.
- Confirm filter condition, blower operation, and coil cleanliness before replacing any controls — start by ruling out whether ohm out both the outdoor coil sensor and outdoor air temperature sensor against their resp….
- Measure airflow-related readings that match the symptom, such as temperature split or static pressure, and check whether check all sensor wiring for shorts or crossed connections.
- After the correction, run the system long enough to confirm the air conditioners fault does not return under normal load.
Still unsure about this fault?
ACLogics walks you through Carrier Air Conditioner diagnostics step-by-step — so you confirm the cause before swapping parts.
