High Lockout
Fn on Ideal Logic Combi C24 C30 C35

Your boiler has lit correctly but the flame has gone out unexpectedly, often due to a temporary interruption in the gas supply or a blocked condensate pipe.

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 Loss

What causes this fault?

This fault happens when the boiler successfully starts up, but the flame goes out shortly after because the system can no longer detect it. The most common reasons are a lack of gas entering the unit, a dirty sensor that can't 'see' the flame, or a blockage in the pipe that carries away waste liquid.

This fault is frequently seen during freezing winter spells, as the external condensate pipe can freeze solid and cause the boiler to shut down for safety.

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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