High
E01 on Atag Q 25CR

Your boiler has failed to ignite the flame needed to produce heat or hot water, usually because the gas supply is interrupted or the ignition system is blocked.

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

error code

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 →E04View →

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