High
No mains LED on Worcester Bosch 24i RSF

Your boiler has completely lost power and is unable to turn on, likely due to a blown fuse or a failure in the electrical control board.

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

Failure of mains supply, blown fuse (F1 2ATHRC or F2 1.25AT), or faulty PCB.

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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