High
F0 263 on Worcester Bosch Greenstar Heatslave II

Your boiler has briefly lost electrical power and is now waiting for you to manually restart it to resume normal operation.

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

Mains power loss restored. Any CUS lockout - Blue light flashing. Press reset button.

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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Related fault codes

F0 263View →

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