High Lockout
F7 on Ideal Logic Max Plus

Your boiler is not receiving enough electrical power from the grid to operate safely and has shut down as a precaution.

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

Low mains voltage Contact electricity provider

What causes this fault?

This fault occurs when the electrical supply entering your home drops below the minimum level required for the boiler to function safely. The most common reason is an external issue with the local power grid, though it can also be caused by a faulty internal circuit board failing to process the incoming voltage correctly.

This fault can be more common during peak winter periods or extreme weather events when the national grid is under heavy load or power lines are damaged.

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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