High
E01 on Keston Celsius 25

Your boiler has tried to light several times without success, meaning your heating and hot water will not work until the gas supply is restored or the ignition is fixed.

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

Ignition failure – the boiler has attempted to light 5 times and not succeeded – check the gas supply is on

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

E02View →E03View →

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