Low
d.83 on Vaillant Ecomax Condensing 600/800 series

This code is not an actual fault; it is simply an information display showing the total number of times your boiler has started up to heat 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

Number of hot water system cycles (Total)

Engineer required

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

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