Medium
4C on Viessmann Vitodens 200-W B2KA-26

Your boiler has lost track of the water temperature in one part of your heating system, so that section may not heat up properly until a engineer checks it.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Mixer closes. Cause: lead break, flow temperature sensor, heatin (text truncated in source)

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 200 W B2ha B2ka 5772909 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

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All 83 fault codes on the Vitodens 200-W B2KA-26

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

9A9b9C9E9F101819202830384044485051585990919293949899A3A7b0b1b5b7b8bAbbbCbdbEbFC1C2C3C4C5C6C7C8CdCFd6d7d8dAdbdCdddEdFE0E1E3E4E5E7E8EAEbECEdEEEFF0F1F2F3F8F9FAFCFdFEFF

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