BoilerFaultCodesTechnical description
Boiler goes to lock out | No gas; Isufficient gas; Incorrect gas valve adjustment; Electrode defective; Ignition lead defect; Electronic igniter defective
What causes this fault?
This fault occurs when the boiler attempts to ignite several times but fails to establish a consistent flame. The most common reasons include a lack of gas reaching the burner, worn-out spark electrodes that can no longer create a flame, or a faulty gas valve that isn't opening correctly. This effectively acts as a safety shutdown to prevent the boiler from trying to operate without a fire.
This fault is more frequent during the first cold snap of winter, as gas valves and internal components can seize up after sitting idle during the summer months.
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.