My thoughts if youre using a converted keg as a boil kettle is just to make a solid 3/8 tube from copper and a few elbows that is positioned inside the boil kettle. The tube would run from the top of the kettle down the side and then have a 90 degree elbow that would direct flow to the outer perimeter of the kettle forming your whirlpool.
You would then just install a quick disconnect to hook your hose of from the CFC to the kettle. This is what I plan on doing with my HERMS design only out of 1/2 inch.
Another idea that I have seen floating around is using loc-line from McMaster. This is flexible plastic line that can be adjusted to many positions and have many uses. Just search loc-line.
Kegs and Kickstands Brewery
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