High
B. (2) on Potterton Kingfisher 2

Your boiler is failing to stay lit because the safety sensor that detects the pilot flame has lost its connection, preventing the gas from staying on.

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

Main burner fails to light and pilot is extinguished when pressure on the control knob is released - Loose thermocouple connection into control valve.

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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