High Lockout
18 on Glow-worm 30ci Plus

Your boiler's control panel and its main computer are having trouble communicating with each other, meaning you cannot change settings or see the boiler's status correctly.

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

Local user interface fault

What causes this fault?

This fault occurs when the data connection between the front display screen and the boiler's internal computer is interrupted or fails. The most common reason is a loose internal wire or a component failure on one of the circuit boards caused by general wear and tear over time. Because the 'brain' of the boiler can no longer talk to the control panel, the unit stops operating for safety.

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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