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creating a real reverse return system
I will be installing modcon hydronic heating system with 7 cast iron rads supplied/returned via manifolds. I just read up on reverse return, but was wondering, if the supply/return manifolds are located in the same general area, on the same wall in the laundry room is what I was planning, then I can't really see how a reverse return could really be realized. Even if the rad fed on the first port of the supply manifold is returned on the last port of the return manifold, the overall length of the run to that rad is essentially unchanged and as I read it, the idea of the reverse return is to try and make all the runs to each of the emitters essentially the same in order to create (almost) equal flow balance in the system.
The only way I can see this happening in my situation, is either locate the return manifold close to the furthest heat emitter in the system, so that while the furthest heat emitter's supply is furthest from the supply manifold its return is closest to the return manifold, and so on down the line for all the heat emitters, thereby creating somewhat equal length in each heat emitter's total supply-return pipe length.
Or alternatively, if one wishes to keep the manifolds together in the same general vicinity, then change each heat emitter's supply and-or return pipe length, by either taking longer piping routes than necessary, or perhaps by looping coils of pipe for some runs to physically increase the lengths necessary so as to make all heat emitter's overall supply-return pipe length generally equal.
I hope I have explained myself in a way that makes sense, even if what I explained is not entirely correct.