BoilerFaultCodes.com
FL Medium Lockout

Your boiler is displaying an error code for a feature that isn't actually used on this model, which usually indicates a simple electronic glitch or a programming error.

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description: This feature is not required on this appliance

What causes this fault?

This fault occurs when the boiler's internal computer becomes confused and attempts to monitor a component or feature that doesn't exist on this specific model. It is usually triggered by a temporary electronic glitch or the circuit board being programmed with the wrong software settings during a repair or power surge.

Typical repair cost £0-120 (including labour)

DIY fix possible

Locate the reset button on the front control panel.Press and hold the reset button for 2 seconds.Wait for the boiler to restart and check if the code has cleared.

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Protect yourself from future repair bills

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

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