High
Off / Off on Worcester Bosch Greenstar i Junior

Your boiler has lost all power and is completely unresponsive, meaning it is currently unable to provide any heating or hot water.

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

No power at control board. Possible causes: Permanent mains supply to boiler, Boiler mains switch, Fuse F1 (2.5A) or Fuse F3 (0.5A), Transformer (both coils below 100Ω), or replace control board.

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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