High
Block 82 on Atag E32S

Your boiler has detected a faulty sensor that monitors exhaust fumes, so it has purposefully shut down for safety reasons until the part can be replaced by a qualified engineer.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

The flue gas sensor has short-circuited, heat requirement blocked and pump capacity at minimum.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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