Low
S.20 on Vaillant Turbomax Plus VUW 242E

Your boiler is currently working correctly and is simply maintaining its internal temperature so that hot water is available to your taps instantly.

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

Warmstart demand (warm start)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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