High Lockout
4.6 on Ideal Logic Max Heat

Your boiler's fan, which safely pushes exhaust gases out of the flue, has stopped working correctly and is preventing the boiler from firing up.

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

Fan Fault

What causes this fault?

This fault occurs when the boiler's control system loses communication with the fan or detects that it is not spinning at the required speed. The most common reasons are a mechanical failure of the fan motor itself, a loose connection in the internal wiring, or a fault on the main circuit board that prevents power from reaching the fan.

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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