High
E35 on Heatline Sargon 28

Your boiler thinks a flame is present even though no gas should be flowing, which is a safety conflict that stops the system from running.

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

Flame sensing fault: A flame is detected when the gas valve is supposed to be closed.

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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