Reply To: Question on splitting a basboard hot water zone. Graci.

[Harold KestenholzParticipant]

By splitting the manifold where the two pumps are now to add another, you are doing a usual piping arrangement. It is best to run the returns all the way to the return manifold as well. Remember to add a flow control valve (heavy check valve) when you add the new circulator or the other pumps will pump water backewrds through the new pump giving no zone control.
See: http://64.226.150.132/hydronic/multcirc/multcirc.htm