High Lockout
E385 on Baxi Duo-tec Combi

Your boiler has stopped working because it isn't receiving enough electrical power from the mains supply to run 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

Low voltage (less than 195v)

What causes this fault?

This fault occurs when the electrical supply from your home to the boiler drops below the level required for the internal components to operate safely. The most common reason is a wider issue with the local power grid or a faulty printed circuit board that can no longer correctly process the incoming voltage. In some cases, loose wiring or heavy demand from other large appliances on the same circuit can also cause this drop.

This fault is more common during periods of extreme cold or high regional energy demand, as heavy strain on the national grid can lead to temporary brownouts or voltage fluctuations.

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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