Low
D.70 on Vaillant Atmomax

Your boiler is currently stuck in a diagnostic test mode used to check if the internal valve is pointing toward the radiators or the 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

Set diverter valve position

DIY fix possible

Press the 'i' button to exit the information menuTurn the main power switch off and back on again to reset the displayWait 15 minutes for the automatic test sequence to complete

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Related fault codes

D.71View →D.90View →

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