High
Burner goes out on Ferroli Sigma 40 FF

Your boiler is struggling to keep its flame lit, which means it cannot heat your water or home reliably.

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.

Technical description

Insufficient gas supply. Check gas pressure to main burner. Boiler dirty. Check and clean heat exchanger. Burner or injector dirty. Check and clean burner or injector. Faulty flow temperature sensor. Replace flow temperature sensor

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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