Thank you for your reply. I am not at home so can't remember the model exactly and yes you are right it is the flow of hot water.
I will call the installer but thought that as it comes up on the info LED I might be able to diagnose and fix it with help.
Hi
I have a Vaillant Ecoplus boiler which was new in March last year.
When I turn the hot water on it loses pressure and although it remains hot it is very weak pressure.
The info LED reports S17 pump over run.
The rpessure is between 1 and 2 on the dial, .
I have read elsewhere that it...