Low
P.06 on Vaillant Atmomax

Your boiler is currently running a self-diagnostic test to help fill the system with water and remove air pockets.

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

Filling mode test program

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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 approximately 15 minutes for the program to finish automaticallyEnsure the radiator valves are open to allow air to circulate outMonitor the pressure gauge to ensure it stays between 1.0 and 1.5 bar

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