Low
D.4 on Vaillant Atmomax

Your boiler is providing an informational update on the current temperature of its internal warm start feature and is not reporting a fault.

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

Current temperature for warm stat sensor

DIY fix possible

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

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Related fault codes

D.0View →D.40View →

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