High
6 / L on Ideal Maximiser SE

Your boiler has successfully lit, but the flame has unexpectedly gone out while it is trying to heat your home.

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 ionisation (the flame) extinguishes during operation of the unit.

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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