High Lockout
Gas valve(s) on Ideal Concord CXA 40-120

Your boiler is unable to safely control the flow of gas needed to stay lit, so it has shut down to avoid a potential hazard.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

The diagnostics will indicate which gas valve (1 or 2) or solenoid of the double solenoid is at fault

What causes this fault?

This fault occurs when the boiler's internal computer detects that the gas valve is failing to open or close correctly during the ignition process. The most common reasons are a mechanical failure within the valve assembly, a burnt-out electrical coil, or a loose connection in the wiring harness that prevents the valve from receiving 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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