High Lockout
Fn on Ideal Logic Combi ESP1

Your boiler has failed to maintain a flame, which means it has stopped providing heating and hot water to protect itself.

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 occurs when the boiler's control board loses the signal that a flame is present, causing the system to shut down for safety. It is typically caused by a blockage in the condensate drainage pipe, a faulty gas valve, or worn-out ignition components that can no longer detect or sustain a steady flame.

This fault is frequently seen during freezing winter spells, as a frozen external condensate pipe can cause water to back up into the boiler and extinguish the flame.

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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