High
Error 12 on Atag E Range

Your boiler has stopped working because an internal safety fuse responsible for the control power has blown, preventing the system from starting.

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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