High
Burner fails to ignite on Ferroli Sigma 40 FF

Your boiler is trying to start but the flame is not catching, meaning it cannot produce any heat 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

No electricity. Wait for electricity to be restored. Blocked injector. Clean injector. Faulty flow temperature sensor. Replace flow temperature sensor. Faulty gas valve. Repair or replace gas valve. Fan not running. Check that electricity is reaching the fan. Faulty pressure switch or obstructed pipes. Replace the pressure switch or clear the pipes

From this model's manual
Verified against the Ferroli Sigma 40 Ff 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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