BoilerFaultCodesYour boiler is currently preparing to start the heating cycle and is warming up the internal fan.
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: Heating mode fan start-up
What causes this fault?
This code appears when the boiler’s internal computer tells the fan to begin spinning in preparation for a heating cycle. It is a normal part of the ignition process where the fan clears the combustion chamber and ensures a safe flow of air before the gas is lit. If the code stays on screen for a long time, it may suggest 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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