Coaxial Heat Exchanger

[Nyx]

I think i just wasted another coil of 3/8" tubings and 1/2" tubings. After putting the 3/8" tubings i found that it is a little too restrictive (Tube inside Tube). I was actually thinking of running the refrigerant in the 3/8" tubing and the chilled water in the 1/2" tubing.

Anyone has tried such configuration and have good results in it. Or is it better to have 1/4" inch tubings in 1/2" tubings. If this is so my suction line would have to be step down from 3/8" to 1/4". Is it good. I already run out of cash to get bigger tubing and i am now making use of what i have now.

[fatty]

I made a mini cascade with simular spec coaxial hx 1/2" with 1/4" 1/4" for the high side 1/2" for the suction side with r507 and about 93" of captube I get -30 idle on the hx I havent realy load tested it yet

[RussC]

Are you running the water through the 1/4"?

It would seem to me the water through the inner pipe and the refrigerant thought the surrunding pipe. That seems more efficient to me. But bigger the better. Say 1/2" internal for water and 5/8" for the surronding refrigerant?

RussC