Low
P.01 on Vaillant ecoTEC Plus 826

Your boiler is currently running a brief, automated internal test to check its maximum heating capacity and is not showing a fault.

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

Check programme: Maximum load check programme

From this model's manual
Verified against the Vaillant Ecotec Plus 826 installation & service manual, page 22.
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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