Low
P.07 on Vaillant Home System

Your boiler is performing a routine self-cleaning process to remove air bubbles from the pipes and is not currently experiencing 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

Purging the hot water circuit: The function is activated in the small hot water circuit for 4 minutes and then in the heating circuit for 1 minute. 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 approximately 5 to 10 minutes for the automatic purging cycle to complete.Ensure your radiator valves are open to help air move through the system.Check the boiler pressure gauge and top up to 1.5 bar if it has dropped during the process.

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