BoilerFaultCodes.com
8-9 High Lockout

Your boiler has lost its electrical power supply and cannot turn on or heat your home.

Call an engineer soon

Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: No power supply

What causes this fault?

This fault occurs when the boiler's internal computer system is no longer receiving the electricity it needs to operate. The most common reason is a blown fuse on the main circuit board or a failure of the external power switch supplying the unit. In some cases, an internal electrical short or a faulty control board is preventing the power from flowng through the system.

Typical repair cost £90-250 (including labour)

DIY fix possible

Check if other appliances in your home have power.Verify that the boiler's fused spur switch is turned on.Check your home's main consumer unit (fuse box) to see if a circuit breaker has tripped.

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Protect yourself from future repair bills

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