High
4 on Maxol Supacombi HE 24

Your boiler has failed to light after several attempts and has locked itself out for safety.

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.

What the manual says

Manufacturer manual

In the event of failure during an ignition sequence, (5 attempts), the digital display displays error code ‘4’ and the error light will be lit.

From this model's manual
Verified against the Maxol Supacombi He 24 installation & service manual, page 28.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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