High
E4 on Baxi Suprima 60

Your boiler is struggling to light because there might be trapped air in the system or a problem with the gas supply.

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 – try bleeding your radiators

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

E1View →E2View →

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