Fault Codes / Viessmann / AA

Viessmann AA

High

Vitocal — Defrost aborted.

Viessmann AA: Defrost aborted. This fault noticeably affects operation.

Possible causes

Defrost could not be completed.
Low flow / 4-way valve / sensor.

Check steps

Check secondary flow & bleeding.
Check 4-way valve & evaporator sensor.

Affected parts

4-Wege-Ventil
Verdampfer-Temperatursensor

Safety note

Follow F-Gas.

Source: Viessmann resmi servis kılavuzu — Manual p.37: 'AA Abbruch Abtauung' = Vorlauf-/Rücklauftemperatur Sekundärkreis beim Abtauen zu gering. Matches Enthalio DB exactly.

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

Look up in Enthalio →

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