What It Means
Malfunction of power supply or instantaneous power failure.
Daikin Fan Coil
Daikin Fan Coil Error Code U2
Troubleshooting guide for the Daikin Fan Coil system fault U2.
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Possible Causes
- Abnormal power supply voltage.
- Instantaneous power failure.
- Defective main circuit wiring.
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
Malfunction of power supply or instantaneous power failure
All Recorded Causes
Abnormal power supply voltage Instantaneous power failure Defective main circuit wiring
Verify Before Replacing Parts
- Confirm the exact Daikin model family and fan coil 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 abnormal power supply voltage.
- Measure airflow-related readings that match the symptom, such as temperature split or static pressure, and check whether instantaneous power failure.
- After the correction, run the system long enough to confirm the fan coil fault does not return under normal load.
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