Low
578 on Viessmann Vitodens 100-W B1KF-26

The boiler has lost the signal from the room thermostat sensor for its second heating zone, so it can't tell how warm that room is, but it should still heat your home and water safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Lead break, room temperature sensor, heating circuit 2.

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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

577View →579View →

All 151 fault codes on the Vitodens 100-W B1KF-26

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

78111213141516293049505758596263646567686970717273747577788789919295100102103104142161162163176182183184185299345346347348349350351352353354355357359361364365366367368369370371372373374375376377378379380381382383384385386387388395396399400401402403404405406408410416417418425446447448449451452453454455456457458461462463464467468471474477517527528540544545574575576577579682683684694738766767799979980981982E10E12

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