Low
A5 on Atag A200

Your boiler is struggling to detect the outdoor temperature, but it will continue to heat your home using its internal settings as a backup.

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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