Hi all, fitted a new rad on the ground floor of a small house with a worser bodge combi. Pipe work running from the room above. There was already a loose board upstairs which I lifted and teed into "flow & return", filled up and everything was pretty as a picture until I fired her up... No heat in rad. To cut a long story short, I lifted more boards until I discovered I'd teed into the branches to the upstairs rad off a one pipe system. So I teed into the main run, no improvement; built an injector tee with a 15-22 reducer, slightly warm. Ran out of time & need to go back. I was thinking I might run the flow into the top of the rad (both valves currently at the bottom). Does anyone have any bright ideas?