Low
P.00 on Vaillant ecoFIT Pure 425

Your boiler is currently running a self-cleaning air removal cycle to clear trapped air from the system pipes.

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

Purging check programme: The internal pump is cyclically actuated. The heating circuit and the hot water circuit are purged via the automatic air vent (the cap of the automatic air vent must be released).

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 15.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Ensure the small black cap on the automatic air vent inside the boiler casing is unscrewed slightly to allow air to escapeMonitor the boiler for 15-20 minutes to see if it automatically completes the cycleCheck your system pressure gauge is between 1 and 1.5 bar, topping up if necessary

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