Hello Tony
Sorry, to answer your questions,
Why did you stick with this incompetent fellow for four years?
Well its been 3 winters, with all his Vaillant talk and being the installer I thought he was able but yes I made an error here choosing this bloke , I wish now the heating had stopped working completely and then I would have insisted Vaillant call under warranty, I would like to point out that when one has a new boiler, told it is one of the top manufacturers and pay much more you do not expect problems and I was not around much due to business so it was a message from my wife and I called the installer, again my error I should have given this more attention but I simply did not have the time.
Cleaning the HE means the system is dirty. Thats the installers responsibility to clean the system. Why did he not power flush it when he fitted the boiler?
He did not power flush when the boiler was installed, he said the system was clean, not required and would cost £1000 more, he did add inhibitor.
What installation errors caused Vaillant to tell you to get the installer to solve?
I phoned vaillant stating the boiler had a problem with the heating and they said the 2 year warranty is covered by the installer, it seemed a reasonable course of action at the time.