High Lockout
16 on Glow-worm Ci Plus

Your boiler has detected an issue with the internal valve that controls the flow of gas, causing the system to shut down for safety purposes.

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

Gas safety value failure

What causes this fault?

This fault occurs when the boiler's control board detects that the internal gas valve is not opening or closing correctly, or is drawing an incorrect electrical current. The most common reason is an electromechanical failure within the valve itself, though it can also be caused by a faulty circuit board sending the wrong signals to the gas assembly.

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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