BoilerFaultCodes.com
S.20 Low

Your boiler is perfectly healthy and is simply letting you know that it is currently preparing or providing heat to your radiators or hot water cylinder.

Technical description: Warnstar demand
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.20 — no call-out fees, no surprises.

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