Low
P.06 on Vaillant Home System

Your boiler is currently running an automatic maintenance program to remove trapped air bubbles from the heating 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 the heating circuit: The diverter valve is moved to the heating position. The function is activated in the heating circuit for 15 minutes. The pump runs and stops at regular intervals.

From this model's manual
Verified against the Vaillant Home System installation & service manual, page 28.
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

Wait 15 minutes for the program to complete automaticallyCheck your radiator valves are open to help air move throughMonitor the boiler pressure gauge to ensure it stays between 1 and 1.5 bar

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