Daikin VRV

Daikin VRV Error Code U3

Troubleshooting guide for the Daikin VRV system fault U3.

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What It Means

Check operation not executed or transmission error.

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

  1. Confirm the exact Daikin model family and vrv context before acting on a generic code description.
  2. Start with the exact model documentation and verify the full operating sequence before replacing parts, particularly around check operation is not executed.
  3. 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.
  4. After the correction, run the system long enough to confirm the vrv fault does not return under normal load.

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