Warren Controls’ three-way valves are available in both mixing and diverting, with bronze or cast-iron bodies, and bronze or stainless-steel trim. 

Flo-Trol automatic flow control valves are designed to give constant flow over wide pressure ranges. 

John Siegenthaler's been designing hydronic heating systems for 25 years, and he still comes across little nuances that when ignored can bring a system that is 99.9% correctly designed and installed to a virtual standstill.