Medium
98 on Viessmann Vitodens 200-W B2KA-35

A temperature sensor inside the boiler appears to have a broken or disconnected wire, so the boiler can't read the water temperature correctly and may stop or run less efficiently until it is checked.

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

Lead break, temperature sensor

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-35

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

4C9A9b9C9E9F1018192028303840444850515859909192939499A3A7b0b1b5b7b8bAbbbCbdbEbFC1C2C3C4C5C6C7C8CdCFd6d7d8dAdbdCdddEdFE0E1E3E4E5E7E8EAEbECEdEEEFF0F1F2F3F8F9FAFCFdFEFF

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