Medium
db on Viessmann Vitodens 200-W WB2C 35kW Combi

The boiler's room thermostat for your second heating zone has stopped sending a reliable temperature reading, so that zone is now heating based only on outside weather readings and may not hold the exact room temperature you set.

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

Control mode without room influence: Short circuit, room temperature sensor, heating circuit 2 (with mixer)

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 200 W Wb2c Service 5692857 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 82 fault codes on the Vitodens 200-W WB2C 35kW Combi

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

4C9A9b9C9E9F1018202830384044485051585990919293949899A7b0b1b5b7b8bAbbbCbdbEbFC1C2C3C4C5C6C7C8CdCECFd6d7d8dAdCdddEdFE0E1E3E4E5E7E8EAEbECEdEEEFF0F1F2F3F8F9FAFCFdFEFF

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