DAI

Daikin U2

Critical

Altherma — Power supply malfunction / brief power failure.

Daikin U2: Power supply malfunction / brief power failure. This fault typically halts operation and needs immediate attention.

Possible causes

Abnormal supply voltage / voltage dip.
Faulty main circuit wiring.

Check steps

Measure supply voltage all phases.
Check main wiring & terminals.

Affected parts

Hauptplatine
Verdrahtung

Safety note

De-energise before work.

Source: Daikin resmi servis kılavuzu — Daikin SM-TS3 official chart (daikin.com): 'U2 — Dysfonctionnement provoqué par l'alimentation électrique ou une panne de courant instantanée' = 'Malfunction caused by power supply or an instantaneous power failure' — matches app's 'power supply fault / brief power outage' exactl…

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

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