I am trying to get my head around the whole UVC/ASHP/UFH setup at the minute but before I get into that I have a query about how to splice multiple manifolds together.  In my setup I have UFH on both the ground and first floors, heat will be provided via a buffer vessel, so there will be a manifold upstairs and another on the ground floor. I have seen low loss headers mentioned on a few threads but don't understand their application as such. With my setup what would be the ideal way of connectin