Low
S.20 on Vaillant Turbomax Plus 828

Your boiler is temporarily pre-heating its internal water tank to ensure you get hot water quickly when you turn on the tap.

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

Warmstart demand (warm start)

DIY fix possible

No action is required as this is a normal operational status message.If you wish to stop this from happening, turn the 'Comfort' or 'Warmstart' dial to the 'off' position.Check your user manual to see how to disable the pre-heat function if you prefer to save energy.

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