High
01 on Saunier Duval Thema Classic F24E Plus

Your boiler is failing to light because it is not receiving gas or cannot sense a flame, meaning you currently have no heating or hot water.

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

Ignition fault (lockout) caused by no gas, no detection

From this model's manual
Verified against the Saunier Duval/Saunier Duval Boiler Themaf30eplus 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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Related fault codes

02View →03View →

All 22 fault codes on the Thema Classic F24E Plus

Seeing a different code? Every code this model can display, in one place.

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