High
On / Off (General fault) on Worcester Bosch Greenstar i Junior

Your boiler has stopped responding to requests for heat or hot water and is stuck in a non-operational state.

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

Boiler not operating during any demand. Check: Fan, 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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