BoilerFaultCodesTechnical description
Boiler at Lock-Out
What causes this fault?
This fault occurs when the boiler has tried to ignite several times but failed to detect a stable flame, leading the system to shut down for safety. The most common reasons are a lack of gas reaching the burner or a worn-out component failing to spark or sense the flame correctly. It essentially means the boiler’s internal computer has lost confidence that it can burn fuel safely.
This fault can be more frequent during the first cold snap of autumn when internal components that have been sitting idle all summer are suddenly stressed or seized.
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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