Viessmann 2C

High

Vitocal — Open circuit, reversible suction gas temperature sensor — in heating mode the heat pump keeps running, in cooling mode the compressor switches off.

Viessmann 2C: Open circuit, reversible suction gas temperature sensor — in heating mode the heat pump keeps running, in cooling mode the compressor switches off. This fault noticeably affects operation.

Possible causes

Suction gas sensor (Pt500A) open circuit.

Check steps

Check resistance (Pt500A) at terminals X25.15/X25.16, replace sensor if needed.

Affected parts

Sauggasfühler

Safety note

Isolate power before testing.

Source: Viessmann Vitotronic 200 Typ WO1C Serviceanleitung für die Fachkraft (2017-01), "Übersicht der Meldungen" §Störungsbehebung, Art.-Nr. 5813961

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

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