3-way vs 4-way hot water mixing

[coldmaster]

Anyone have a rationale as to when to apply a 3-way vs 4-way mixing valve on a hyrdonic system? Looking to mix down water to ~120F from a ~180F hot water heating system.

Thanks in advance...

 

[hydtools]

Common way looks like 3-way valve. Hot one port, cold second port and mixed third port.

http://www.houseneeds.com/shop/Heatingproducts/HydronicHeating/mixingvalves/tacomixingvalvepopup.htm

If you have two loops, then 4-way.

http://www.comfortableheat.net/pdfs/continuous.pdf

Ted

 

[hydtools]

Also reference this Taco information:

http://www.taco-hvac.com/uploads/FileLibrary/102-145.pdf

Ted