BoilerFaultCodes.com
8.F Emergency Lockout

Your boiler has detected a flame when there shouldn't be one, which usually means a internal component is stuck or damaged.

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.

Technical description: Permanent ignition

What causes this fault?

This fault occurs when the boiler's sensors detect a flame still burning even after the heating or hot water has been turned off. The most common reason is an internal component like the gas valve becoming stuck open or an electrical failure on the main control board that keeps the ignition system active. Because this involves gas flow that isn't being controlled properly, the boiler shuts down immediately as a safety precaution.

Typical repair cost £180-350 (including labour)

Engineer required

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

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

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Protect yourself from future repair bills

A boiler cover plan would cover faults like 8.F — no call-out fees, no surprises.

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