Viessmann 18

Medium

Vitocal — Outside temperature sensor — open circuit.

Viessmann 18: Outside temperature sensor — open circuit. This fault usually isn't an immediate stop, but should be checked soon.

Possible causes

Sensor (Ni 500) interrupted.

Check steps

Check resistance (Ni 500) at connector F0.
Check/replace lead & sensor.

Affected parts

Außentemperatursensor (Ni 500)

Safety note

Isolate power.

Source: Viessmann resmi servis kılavuzu — Serviceanleitung WO1C, section '18 Außentemp.sensor' (p.90): 'Ursache: Unterbrechung Außentemperatursensor.'

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

Look up in Enthalio →

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