High Lockout
No light on Worcester Bosch Greenstar Ri

Your boiler appears to have no electrical power at all, meaning the screen and lights are completely blank and it will not 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

What causes this fault?

This fault occurs when the boiler's electrical circuit is broken, preventing the internal components from receiving the electricity they need to operate. The most common reason is a blown fuse on the main control board, often caused by a power surge or a failing internal part like a pump or valve short-circuiting the system.

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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