Low
d.2 on Vaillant Ecomax Condensing 600/800 series

Your boiler is currently in a brief, normal safety pause to prevent it from switching on and off too frequently.

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

Maximum burner anti cycling period at 20 °C flow temperature

Engineer required

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

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Related fault codes

d.1View →

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