The only time that the mix valve will be bringing in fresh, cold water is when there is a demand from the fixtures. Ideally, the mixing valve would be at the point of distribution (tank or hot water source) and it would mix down the high temp water to whatever temperature you desire using the slightly cooler water from the recirculation return. Take a look at our technical brochure for some application diagrams that may be helpful.
Hello Saul,
The only time that the mix valve will be bringing in fresh, cold water is when there is a demand from the fixtures. Ideally, the mixing valve would be at the point of distribution (tank or hot water source) and it would mix down the high temp water to whatever temperature you desire using the slightly cooler water from the recirculation return. Take a look at our technical brochure for some application diagrams that may be helpful.
https://www.caleffi.com/sites/default/files/file/01050_17_na.pdf
Best Regards,
Cody Mack
Caleffi North America