BoilerFaultCodesYour boiler is currently preparing its internal fan to safely clear any leftover gases before it begins the ignition process.
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: fan pre-run
What causes this fault?
This is not actually a fault, but rather a normal part of the boiler's starting routine where the fan spins up to clear the combustion chamber. It occurs every time there is a demand for heating or hot water to ensure the system is safe to ignite. If the code stays on the screen for a long time without the boiler firing up, it may indicate that the fan is struggling to reach the required speed.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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A boiler cover plan would cover faults like S.01 — no call-out fees, no surprises.
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