Medium Warning
dA on Viessmann Vitodens 050-W

Your boiler has lost its connection to the indoor temperature sensor for your main heating area, meaning it cannot accurately tell how warm your rooms are.

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

Room temperature sensor heating circuit A1 shorted out

What causes this fault?

This fault occurs when the electrical signal from your indoor temperature controller is interrupted or becomes inconsistent. The most common reason is a loose connection in the wiring or a failure of the internal sensor component that detects the heat level in your home.

Engineer required

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

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Related fault codes

b1View →b7View →

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