Hi Everyone, I've been lurking here for a few months and the information has been just great. Now I have made up my mind on which gassifier to buy. I'm now in the process of purchasing a Tarm Solo 40 with the storage. I've received lots of info from Tarm as far as how to hook the boiler into the system. I do have some general plumbing questions though. 1) I already have a pressure reducing valve and back flow preventer. Do I need a second for the Tarm unit of can I just put a tee after the one that I presently have? 2) I'm putting in ball valves between the Tarm and the manifold and the oil boiler and the manifold on both supply and return lines. I'm doing this for redundancy. If I ever have a problem with one, I can isolate it completely from the system. When putting in boiler drains near the isolation valves, where should the boiler drain go, before the ball valve or after? 3) I'm probably going to go with Webstone 50615 combined ball valve and boiler drain valves. Does anyone have a opinion on these combination valves?