50′ Dual Coil Copper Immersion Chiller Build

This is my dual coil chiller. I opted for 3/8″ ARC Type L tubing below the split, and 1/2″ above the split. The 1/2″ parts are rigid Type K copper.
I needed reducers from 1/2 rigid to 3/8″ tubing in order to make the connections. I couldn’t source them locally so I needed to order them online. Because of the switch from soft tubing to rigid, you actually need to use 1/4″ to 1/2″ fittings. They are pretty rare. I found some on Amazon that were pretty pricey for what they were, but they got the job done.


I used a kitchen pot which was the right diameter to fit the inside of my boil kettle. In my case that was about 10″.


Starting to form the copper around the pot.


Almost done with one coil.



Test fitting the coils in the pot.

The two coils after bending. The next step was to interlace the coils.


Various Fittings


Misc. parts for the splitter
Misc. parts for the split-er


This is the chiller when it is almost done. You can notice that I used some copper wire to stitch the coils together to keep it all rigid.


The various parts of the Y split-ers before being soldered.


I wanted to include a recirc line for my pump on the chiller. I didn’t want to hard solder it onto the chiller so I could separate it and clean it. I came up with this solution. I took a copper sweat union, cut it length ways, then used a sheet metal pliers to bend it into the shape shown. I made two and soldered them back to back. I inserted a piece of copper wire between them in a ‘U’ shape to let it take more solder and strengthen the joint.


The finished product.