Viessmann 31

Medium

Vitocal — Primary return temp sensor fault.

Viessmann 31: Primary return temp sensor fault. This fault usually isn't an immediate stop, but should be checked soon.

Possible causes

Sensor (Pt 500) shorted or open.

Check steps

Check resistance (Pt 500) at connector.
Replace sensor if faulty.

Affected parts

Primär-Rücklaufsensor (Pt 500)

Safety note

Isolate power.

Source: Viessmann resmi servis kılavuzu — Manual p.29: '31 Rücklaufsensor primär' = Kurzschluss Rücklauftemperatursensor Primärkreis. Matches Enthalio DB.

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

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