Fault Codes / Daikin / U4-01

DAI

Daikin U4-01

High

VRV / Sky Air — Indoor ↔ outdoor communication error — wiring.

Daikin U4-01: Indoor ↔ outdoor communication error — wiring. This fault noticeably affects operation.

Possible causes

F1/F2 line faulty / polarity.

Check steps

Check F1/F2 connection & polarity.

Affected parts

F1/F2-Leitung

Safety note

Low voltage — work carefully.

Source: Daikin VRV Service Manual — U4 sub-code

Reviewed by Anıl Güzeldemir — in the refrigeration machine room since 2006, developer of Enthalio.

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