Medium
bE on Viessmann Vitodens 300-W

Your boiler is having trouble communicating with your wall-mounted room thermostat because the settings weren't configured correctly during installation or after a power cut.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Technical description

Control mode: Vitotrol remote control incorrectly encoded

Engineer required

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

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Related fault codes

b7View →bFView →bcView →

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