Counterflow chiller design question

[jguthner]

This CFC got thrown in with a couple keggles I bought I bought. The design looks a little funky to me and I can't find anything online that replicates it.

I'm assuming the inner copper pipe will connect with appropriately sized tubing and hose clamps. The barbs kind of throw me off though, because they're different sizes. The smaller one is 3/4 x 1/2, and the larger one has the markings scratched off.

• Why 2 different sizes?
• What's the best way to connect the "water in" side to a standard garden hose? Cut off a garden hose and clamp it to the barb?

 

[logdrum]

That seems mighty small to be chilling anything. If you're set on using it, I would replace both barbed fittings with 3/4" NPT x garden hose fittings:
https://www.amazon.com/dp/B00S84L71G/?tag=skimlinks_replacement-20

There's one for female garden hose as well

 

[ryan810cows]

My guess is the smaller fitting is your inlet and the larger is your outlet. That way you don't have any flow restriction. Also, those both look like 3/4" NPT threads. I would adapt them to a 3/4" NPT to Garden Hose (One male and female). McMaster Carr has fitting too.

As for the total length, it looks a bit small. I use a 30' coil. It just may take some time to cool.