BoilerFaultCodes.com
38 High Lockout

Your boiler has started an ignition process but lost its flame unexpectedly, causing the system to shut down for safety.

Call an engineer soon

Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Loss of flame rectification

What causes this fault?

This fault occurs when the boiler successfully lights the burner but fails to detect a consistent flame signal shortly after. The most common reasons are a worn-out sensing probe that can no longer 'see' the fire, or an unstable gas supply preventing a steady flame from being maintained.

This fault can appear more frequently during the first cold snap of autumn when the gas valve or electrodes struggle to operate after sitting idle all summer.

Typical repair cost £100-280 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Protect yourself from future repair bills

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