High Lockout
17 on Glow-worm Ci Plus

Your boiler is not receiving enough electrical power from your home's mains supply to operate safely.

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

Power supply <170V

What causes this fault?

This fault occurs when the electrical supply entering your boiler drops to a level that is too low for the internal components to function. It is usually caused by a wider problem with the local power grid or a fault within your home's electrical wiring that prevents the boiler from receiving a steady 230V flow. In some cases, it can also mean the boiler's internal control board is failing to correctly process the incoming power.

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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