BoilerFaultCodesTechnical description
The safety devices have been activated (lockout)
What causes this fault?
This fault occurs when the boiler's safety sensors detect a failure in the ignition process or a consistent loss of flame during operation. The system shuts down to prevent unburnt gas from building up, often triggered by a worn-out ignition spark, a faulty gas supply, or a communication error within the internal electronics.
This fault can be more frequent during the first cold snap of winter when components that have sat idle all summer are suddenly put under high operational stress.
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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