BoilerFaultCodesTechnical description
Boiler has gone to a lockout condition. (Character A is shown on the status/function display and a number i.e. 01 shown on the temperature/settings display)
What causes this fault?
This fault occurs when the boiler tries to start but can't detect a flame, causing the system to shut down for safety. It is usually caused by worn-out ignition parts that can't create a spark or a gas valve that isn't opening correctly to let fuel into the burner.
This issue often surfaces during the first cold snap of autumn when the boiler is pushed to work harder after being idle all summer.
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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