Daikin A0

High

VRV / Sky Air — External protection device activated.

Daikin A0: External protection device activated. This fault noticeably affects operation.

Possible causes

External (field) contact open/tripped.
Loose wiring at input.

Check steps

Check external safety loop & jumper at input.
Identify the tripping external device.

Affected parts

Kein Ersatzteil — Einstellung/Konfiguration prüfen (DIP, Menü, Untercode)

Safety note

230V — isolate power.

Source: Daikin SM-TS3 (Simple Self-Diagnosis by Malfunction Code, resmi) veya VRV IV+ Service Manual (ManualsLib) — SM-TS3 p.3: 'A0 External protection device activated — External protection device connected to the terminal strip T1-T2 of indoor unit is activated.'

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

Look up in Enthalio →

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