Low
D.2 on Vaillant Atmomax

Your boiler has temporarily paused its burner to prevent it from switching on and off too frequently, which helps protect the internal components and improve efficiency.

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

Max burner anti-cycling period at 20c flow temperature

DIY fix possible

Wait approximately 15 to 20 minutes for the countdown to end naturallyEnsure your room thermostat is turned up higher than the current room temperatureCheck that your radiator valves are open to allow heat to dissipate

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Related fault codes

D.0View →D.1View →

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