Low
S.20 on Vaillant Home Combi

Your boiler is currently operating normally as it prepares to provide hot water to your taps or shower.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

Hotwaterhandlingmode:Requirement

From this model's manual
Verified against the Vaillant Home Combi installation & service manual, page 34.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

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

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