High
Pictogram of a spark on Saunier Duval Isomax F30E

Your boiler is failing to light the flame, which is likely due to a lack of gas reaching the unit or a problem with the ignition system.

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

No gas supply

From this model's manual
Verified against the Saunier Duval Isomax F30e installation & service manual.
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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