I am interested to hear people ideas too, my plan for my 25 ft 3/8” copper IC to HERMs coil was a bit ghetto:
I wanted to be able to move the heat exchanger from the HLT to the BK and use it as both a HERMs and a IC, so there are no hard connections in the kettle. Everything will be connected via cam locks.
Short PEX line attached to each end of the copper coil with a stainless worm clamp (the PEX just barely slides onto the copper when warm). Then a sharkbite fitting to ½” male NPT. Then ½” female NPT to camlocks.
My biggest concern is the PEX connection with worm clamp. It worked without leak for 30+ brews as an immersion chiller but I suspect that the constant high temps during mash recirculation may cause that connection to fail at some point.