Low
S.23 on Vaillant Turbomax Plus 828

Your boiler is currently preparing itself for a warm start to ensure you have hot water quickly when you turn the tap on.

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.

Technical description

Ignition sequence (warm start)

DIY fix possible

No action is required as this is a normal status code, not a fault.If you wish to stop the boiler from pre-heating, you can turn off the comfort/warm start function using the control dial.Ensure your thermostat is set to the desired temperature if you have no heating.

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Related fault codes

S.20View →S.24View →S.21View →

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