Counter Flow Chiller Needs

[brewgar]

I went and bought the same 1/10 horsepower pump you used from Freight Harbor today. Will add fittings to required hose sections and use the system on my next brew day. Har!

 

[DocDriza]

When it comes to a CFC, does it make sense to have the 1/2" or 3/8"? I understand why the larger the better for an IC, is the same concept true for a CFC?

 

[tnlandsailor]

It's going to depend on how cold your chill water is. A larger diameter means you can flow a lot more wort but if your chill water isn't very cold, then there won't be enough heat transfer to chill that larger wort flow. You can pretty easily get 1 GPM out of 3/8" OD tubing with even a modest pump, and you will need a good flow of 60ish F (or lower) water to chill to 68 F. In a 1/2" OD tube, your flow rate can increase by about 75%. With the same chill water supply, you might find yourself metering the wort flow down to make sure the exit temp is where you want it, which negates the benefit of the larger tube for more flow.

In short, don't go larger on the wort line unless you have a adequate chill water to pull off the larger flow.

 

[DocDriza]

It's going to depend on how cold your chill water is. A larger diameter means you can flow a lot more wort but if your chill water isn't very cold, then there won't be enough heat transfer to chill that larger wort flow. You can pretty easily get 1 GPM out of 3/8" OD tubing with even a modest pump, and you will need a good flow of 60ish F (or lower) water to chill to 68 F. In a 1/2" OD tube, your flow rate can increase by about 75%. With the same chill water supply, you might find yourself metering the wort flow down to make sure the exit temp is where you want it, which negates the benefit of the larger tube for more flow.

In short, don't go larger on the wort line unless you have a adequate chill water to pull off the larger flow.

This makes sense. I think I'm going to go with a double pipe CFC and go with the DIY option. Based on what you say here, I think, I'm going with 1" PVC pipe with 1/2" copper. I think your concept still applies and works here.