Medium
db on Viessmann Vitodens 300-W

Your boiler has lost signal from the temperature sensor that controls your second heating zone, meaning it cannot correctly regulate the warmth in that specific part of your home.

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

Heating circuit M2 room temperature sensor shorted out

Engineer required

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

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