High Lockout
GAS VALVE FAULT on Ideal Concord CXA 40-120

Your boiler is unable to safely control the flow of gas needed to stay alight, so it has shut down as a safety precaution.

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

Malfunction of gas valve 1 or 2 or solenoids. Check wiring, gas pressure, or replace faulty gas valve/solenoid.

What causes this fault?

This fault occurs when the boiler's internal computer detects that the electronic valves responsible for letting gas into the burner are not opening or closing correctly. The most common reason is that the mechanical seals inside the valve have become stuck or the electrical coils that trigger them have burnt out, preventing the boiler from lighting safely.

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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