High
Blank display on Keston C55

Your boiler has lost power entirely, which could be due to a simple tripped switch or an internal electrical failure.

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 from the boiler or mains power loss lasting more than 8 hours

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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