High
Ignition Lockout on Potterton Promax 15 & 24

Your boiler has failed to start because it cannot successfully light or maintain a flame, so it has safely shut itself down to prevent gas buildup.

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

The pump, fan, spark generator and gas valve are switched off. If a flame is not detected within 5 seconds and 5 ignition attempts have been made. The boiler can only be reset by manually using the thermostat knob.

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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