Low
A5 on Atag Q 25CR

Your boiler has lost communication with the weather sensor installed outside your home, so it is using a standard indoor setting instead.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Outside temperature (only if an outside sensor is connected)

Engineer required

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

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