Viessmann D3

Critical

Vitocal — Low-pressure fault, compressor switches off.

Viessmann D3: Low-pressure fault, compressor switches off. This fault typically halts operation and needs immediate attention.

Possible causes

LP switch tripped or sensor faulty.
Evaporator fouled, fan blocked/faulty.

Check steps

Clean evaporator, check fan.
Check gauge, primary pump & LP switch/sensor.

Affected parts

Niederdrucksensor
Niederdruckschalter
Primärpumpe

Safety note

Refrigerant under pressure – technician only.

Source: Viessmann resmi servis kılavuzu — Serviceanleitung WO1C, section 'D3 Niederdruck' (p.109-110): 'Verdichter schaltet aus. Ursache: Niederdruckstörung: ... Niederdruckschalter hat ausgelöst / Niederdrucksensor hat Fehler gemeldet.'

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

Look up in Enthalio →

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