BoilerFaultCodes.com
Gas Valve Fault High Lockout

Your boiler has detected an electrical issue with the gas control system and has shut down as a safety precaution.

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: Contact electricity provider

What causes this fault?

This fault occurs when the boiler's main control board loses the ability to communicate with or power the gas valve properly. The most common reason is an internal electrical failure within the valve's solenoid or a communication break in the wiring harness connecting the components. As the boiler cannot safely regulate the flow of fuel, it shuts down immediately to prevent any risk.

Typical repair cost £250-£450 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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