Fault Codes / Viessmann / B7

Viessmann B7

High

Vitocal — KM-BUS communication outdoor unit.

Viessmann B7: KM-BUS communication outdoor unit. This fault noticeably affects operation.

Possible causes

Link to outdoor unit interrupted/faulty.
Coding/address wrong.

Check steps

Check KM-BUS to outdoor unit & connectors.
Check outdoor unit coding switches.

Affected parts

Außeneinheit
KM-BUS-Leitung

Safety note

230/400V — isolate power.

Source: Viessmann resmi servis kılavuzu — Manual p.40: 'B7 KM-BUS Außeneinheit' = Kommunikationsfehler mit Kältekreisregelung Außeneinheit. 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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