High
No light on Worcester Bosch Greenstar i Junior

Your boiler has completely lost power and is not showing any lights or signs of life.

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

Check: Permanent mains supply to boiler; Boiler mains switch on; Fuse F1; Fuse F2; Transformer (both coils below 100Ω); Otherwise replace control board (if boiler does not operate correctly).

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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