Low
P.00 on Vaillant ecoTEC Pro 30

Your boiler is currently running a self-diagnostic sequence to automatically remove trapped air from the system.

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

From this model's manual
Verified against the Vaillant Ecotec Pro 30 installation & service manual, page 18.
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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