High
E01 on Baxi Promax Ultra

Your boiler has failed to light, which means it cannot heat your water or your home, usually due to a lack of gas or a problem with the ignition spark.

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 or gas supply fault

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 →

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