High Lockout
F7 on Ideal Logic Combi ESP1

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 voltage required for the boiler's sensitive electronics to function. While it is often caused by a temporary dip or brownout in the local power grid, it can also be triggered if the boiler's internal control board develops a fault and can no longer process the incoming power correctly.

This fault can be more common during periods of extreme cold or heatwaves when the national electricity grid is under high demand, leading to localized voltage drops.

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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