Low
d.72 on Vaillant Ecomax Condensing 600/800 series

Your boiler is correctly performing a routine check to ensure the water inside is being circulated and heated properly for your hot water supply.

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.

What the manual says

Manufacturer manual

Pump over run (for loading warmstart) (ecoMAX 800)

From this model's manual
Verified against the Vaillant Ecomax Condensing 600 800 Series installation & service manual, page 47.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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