Im trying to fit a neutraliser, it only has 8 tappings, should i combine the cold feed and vent into 1 port and use a 28mm? Also, im using layout 2 explained on their website as instructed by dunsley , can anyone take 5 mins to answer my question in what is the point of the injector tee? The return from the woodburner goes to one port and is connected into the space heating return via an injector tee that does something with the heatleak radiator and a 2 port n.c motorised valve, i cant get my head around how to pipe it up. Thanks