BoilerFaultCodesTechnical description
Burner starting
What causes this fault?
This is a normal operational status rather than a fault, occurring as the boiler's internal computer synchronises the gas valve and fan speeds before ignition. It physically represents the moment the boiler is double-checking all safety sensors are satisfied before it allows the burner to light. The code appears briefly during the pre-purge phase to ensure the combustion chamber is clear and safe to operate.
DIY fix possible
Wait a few minutes for the code to clear automaticallyCheck if there is a demand for heating or hot waterReset the boiler only if the code remains frozen for more than 5 minutes
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