BoilerFaultCodes.com
S.1 Low Information

Your boiler is currently preparing to start the fan as part of its normal ignition process.

Monitor it

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 start

What causes this fault?

This status code appears when the boiler's internal computer sends a signal to the fan to begin spinning before ignition. It is a natural part of the start-up sequence where the fan clears the combustion chamber and prepares the correct air-to-gas ratio. If the code stays on screen for a long time, it usually means the fan is struggling to reach the required speed or is not communicating back to the main board.

Typical repair cost £0 (including labour)

DIY fix possible

This fault may be fixable without an engineer. Check your manual first.

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Protect yourself from future repair bills

A boiler cover plan would cover faults like S.1 — no call-out fees, no surprises.

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