High
E04 on Ariston Egis 24 MFFI

Your boiler is failing to light the gas burner after several attempts, meaning you will not have any heating or hot water until the issue is resolved.

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

if the boiler does not sense that the burner has lit, the error code E04 will appear on the display, should this error occur, the boiler will attempt to relight two more times (20 seconds between each attempt).

From this model's manual
Verified against the Ariston Bravo 24 Mffi installation & service manual, page 56.
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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