High
Error 12 on Atag E22c

Your boiler has stopped working because an internal safety fuse has blown, cutting off the power needed for its control systems to operate.

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

fuse 24 volt/3AT faulty

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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