BoilerFaultCodesTechnical description
The safety devices have been activated (lockout)
What causes this fault?
This fault occurs when the boiler's internal safety software detects an inconsistency during the ignition or combustion process and shuts down to prevent damage. The most common cause is a failure of the main circuit board to communicate correctly with the gas valve or ignition system. It can also be triggered by electrical interference or a component failing to provide the correct feedback during startup.
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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