High Lockout
Gas valve(s) on Ideal Concord CXC 48 116

Your boiler is unable to light because the internal system that controls the gas flow has stopped working correctly.

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

Fault diagnosed related to gas valve 1 or 2, or specific solenoid in a double solenoid gas line.

What causes this fault?

This fault occurs when the boiler's computer detects that the safety valves responsible for letting gas into the burner are failing to open or close correctly. The most common reason is an electrical failure within the valve's internal coils or a communication error from the main control board, which prevents 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.

Find a Gas Safe engineer
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