I enquired about a new boiler one day, it was installed the next, then, nothing but problems. The hot water would get hot, then cooled to tepid. Not enough hot water to fill a bowl to do the washing up. A couple of visits from the company that installed it (Viessmann passed us to them to install it) left us with a boiler with no hot water at all. I spoke to Viessmann who booked one of their engineers to come out to fix the boiler, this took just over a week for the visit. How is it installed so quickly, but waiting over a week to get it fixed. The issue was a faulty pump and gauge, not good for a brand new boiler. Not good service from Viessmann