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.

What the manual says

Manufacturer manual

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

From this model's manual
Verified against the Worcester Bosch 24i Rsf installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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