Viessmann D4

Medium

Vitocal — Control high-pressure fault, compressor off.

Viessmann D4: Control high-pressure fault, compressor off. This fault usually isn't an immediate stop, but should be checked soon.

Possible causes

Air in heating circuit.
Condenser fouled or pump blocked.

Check steps

Bleed heating circuit, check pressure.
Check pumps, flush circuits, check HP sensor.

Affected parts

Hochdrucksensor
Sekundärpumpe
Heizkreispumpe

Safety note

High pressure – caution; technician only.

Source: Viessmann resmi servis kılavuzu — Serviceanleitung WO1C, section 'D4 Regelhochdruck' (p.110): 'Verdichter schaltet aus. Ursache: Hochdruckstörung: Luft im Heizkreis / Sekundärpumpe blockiert / Verflüssiger verschmutzt / Hochdrucksensor defekt.'

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

Look up in Enthalio →

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