Fault Codes / Viessmann / A8

VI

Viessmann A8

High

Vitocal — Heating circuit pump 1 fault.

Viessmann A8: Heating circuit pump 1 fault. This fault noticeably affects operation.

Possible causes

Pump blocked / faulty / wiring.

Check steps

Check pump & wiring.
Free/replace pump.

Affected parts

Heizkreispumpe HK1

Safety note

230V — isolate power.

Source: Viessmann resmi servis kılavuzu — Manual p.36: 'A8 Heizkreispumpe HK1' = Kein Volumenstrom, Umwälzpumpe außer Betrieb. Matches Enthalio DB.

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

Look up in Enthalio →

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