What It Means
Check operation not executed or transmission error.
Daikin Split & Multi-Split
Daikin Split & Multi-Split Error Code U3
Troubleshooting guide for the Daikin Split & Multi-Split system fault U3.
Possible Causes
- Check operation is not executed.
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
Check operation not executed or transmission error
All Recorded Causes
Check operation is not executed.
Verify Before Replacing Parts
- Confirm the exact Daikin model family and split/ multi split context before acting on a generic code description.
- Start with the exact model documentation and verify the full operating sequence before replacing parts, particularly around check operation is not executed.
- Use the listed causes as branches to confirm or eliminate with measurements, not assumptions — the next candidate on the list is a reasonable second branch.
- After the correction, run the system long enough to confirm the split/ multi split fault does not return under normal load.
Still unsure about this fault?
ACLogics walks you through Daikin Split & Multi-Split diagnostics step-by-step — so you confirm the cause before swapping parts.
