Low Information
S.24 on Vaillant ecoTEC Plus 620

Your boiler is working normally and is currently heating up your hot water.

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

DHWmode:Burneron

What causes this fault?

This is actually not a fault, but a status code indicating that your boiler is currently firing to heat your tap water. It appears when someone turns on a hot tap or if the boiler is pre-heating its internal tank to ensure hot water is ready when you need it. Once the demand for hot water stops, this code will naturally change to a different status.

DIY fix possible

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

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Related fault codes

S.20View →S.21View →S.23View →

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