High Lockout
4.13 on Ideal Logic Max Combi

Your boiler's internal computer parts are failing to talk to each other, meaning the system cannot operate or provide heat and hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

No Connection To Primary PCB

What causes this fault?

This fault occurs when the boiler's main control board loses its communication link with the other internal electronic components. The most common reason is a failure of the printed circuit board itself, though it can also be triggered by a loose wiring connection or a faulty user interface display. Because these parts cannot 'talk' to each other, the boiler shuts down as a safety precaution.

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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Related fault codes

F2View →L2View →F1View →

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