High
454 on Viessmann Vitodens 100-W B1KF-35

Your boiler's control settings for a part that manages heating and hot water have become incorrect, so it may not be running as it should, but this is usually fixable by a qualified engineer resetting the settings.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Incorrect parameter set of HBMU heat management unit.

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 high 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

453View →455View →

All 151 fault codes on the Vitodens 100-W B1KF-35

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

78111213141516293049505758596263646567686970717273747577788789919295100102103104142161162163176182183184185299345346347348349350351352353354355357359361364365366367368369370371372373374375376377378379380381382383384385386387388395396399400401402403404405406408410416417418425446447448449451452453455456457458461462463464467468471474477517527528540544545574575576577578579682683684694738766767799979980981982E10E12

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