Low
P.00 on Vaillant Atmomax

Your boiler is currently running a self-cleaning routine to remove trapped air from the pipes and is not actually reporting a hardware 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

The heating circuit and hot water circuit are purged

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 6 to 10 minutes for the program to finish automaticallyEnsure all radiator valves are fully open to help air escapeCheck the pressure gauge and top up to 1.5 bar if it has dropped during the process

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