High
01 on Saunier Duval Themaclassic Plus F30E

Your boiler is failing to light because it cannot detect a flame or is not receiving a gas supply, causing it to shut down 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

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

From this model's manual
Verified against the Saunier Duval Thema F 30 E Plus Combi installation & service manual, page 37.
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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