BoilerFaultCodesYour boiler is performing a routine start-up check by running the internal pump for a few moments before lighting the burner.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: pump pre-run
What causes this fault?
This isn't actually a fault, but rather a normal part of the boiler's ignition sequence. It occurs when the system starts a 'pump pre-run' to ensure water is circulating correctly through the heat exchanger before the gas burner is allowed to light. This safety check prevents the boiler from overheating during the initial start-up phase.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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