High
Ln on Ideal Logic Combi ESP1

Your boiler is struggling to keep its flame lit, which means it cannot heat your water or radiators.

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.

What the manual says

Manufacturer manual

Flame Loss

From this model's manual
Verified against the Ideal Logic Combi Esp1 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's internal computer can no longer detect the flame required to heat the water, causing the system to shut down for safety. The most common reasons are a build-up of carbon on the sensing probes, a blockage in the flue, or an inconsistent supply of gas reaching the burner.

This code can appear during extreme cold snaps if the external condensate pipe freezes, causing 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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