Low
d.22 on Vaillant Ecomax Condensing 600/800 series

Your boiler has received a request to heat your hot water and is operating exactly as it should to fulfill that demand.

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

Domestic hot water demand

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.22View →d.23View →

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