Emergency
370 on Viessmann Vitodens 100-W B1HF-25

The boiler's gas control valve is not shutting off properly, which is a safety concern, so the boiler should be turned off and a qualified Gas Safe engineer called straight away.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Fuel valve or modulation valve will not close.

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 100 W B1hf B1kf 6167586 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

371View →372View →

All 151 fault codes on the Vitodens 100-W B1HF-25

Seeing a different code? Every code this model can display, in one place.

78111213141516293049505758596263646567686970717273747577788789919295100102103104142161162163176182183184185299345346347348349350351352353354355357359361364365366367368369371372373374375376377378379380381382383384385386387388395396399400401402403404405406408410416417418425446447448449451452453454455456457458461462463464467468471474477517527528540544545574575576577578579682683684694738766767799979980981982E10E12

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