Low
D.81 on Vaillant Atmomax

This is an information code rather than a fault, showing you the total number of hours the boiler has spent heating your 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

Operating hours hot water generation

DIY fix possible

No action is required as this is an advisory status messagePress the 'i' button to exit the information menuMonitor the boiler for any actual fault codes (starting with 'F')

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Related fault codes

D.80View →D.82View →D.83View →

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