Low
S.10 on Vaillant Home Combi

Your boiler is simply letting you know that it has received a request to heat up your tap water and is currently starting that process.

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

No action is required as this is a normal operating status code, not a fault.Wait a few moments for the boiler to complete its internal startup sequence.If the boiler stays on this screen for an extended period without providing hot water, try turning the hot tap fully on to ensure the flow sensor detects the demand.

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