Tube-In-Tube HX
 

BeerGrylls,

Here's a photo of the HX (scale is in inches).


...and here's another photo (scale is in inches)...


There is a sticker on the HX that says KOAX CORP. - OKC (I think "OKC" means Oklahoma City, Oklahoma, USA)

And it also says; KOAX P/N: 70310901

And also: MAX WORKING PRES. REFRIG 500 PSIG 3447 KPA

And I weighed it and it comes out to about 5 pounds.

What I can tell you is that the guy I bought it from said it was "good for 1 Ton", but I have not tested or verified that.

From the information on the sticker, you ought to be able to locate official specifications on the Internet.

I can tell you that the original "dust caps" are still in place on the HX and it has never been brazed, never been put into service.

I'll sell it to you for $50 US, and the shipping cost would be additional.

If you need additional info, please ask...

Best,

-AC

Many thanks for the dimensions and pics AC ! I am concerned about the working pressure. My R410a ASHP says it works up to 4.2Mpa, which translates to around 610 psi. Not sure what to do... Also, I tried to email the KOAX people about the specs but it seems the email address is currently invalid, maybe they are completely out of business. I hope it is ok for you to keep it on hold a bit, maybe I find something suitable around here in EU eventually. If you do find more info on it (maybe max test pressure and btu rating) please let me know.
Cheers,
F

Odd,

I find out about a heat exchanger from Austria in this forum and have driven past that plant in Oklahoma City many times . . . .

Actually thought they made cable (coax), - well silly me!

Steve

BeerGrylls,

I did some serious research, and from the best I could determine, KOAX was last really viable around 2004-2005. So no information will come from them.

Then I looked for similar products that I could use for comparison.

I went to THIS_PAGE and saw a table of Coaxial Helical HXs that were of similar dimension. I then did a linear regression of the data in table and made a very rough extrapolated estimate of the capacity of the HX I have in the photo.

Turns out that it's capacity will fall far short of your needs, as it will only handle about 3470 BTU/hr which would be about 1 kWatt, if I have my conversion correct.

So I'm afraid that the pressure issue is of no consequence now.

Sorry I didn't work it out before I bought the HX, and I am glad I worked this out before the HX went to Austria. I wouldn't want to let you down.

I might still find a use for them in a very small application... maybe a de-superheater or something.

Sorry I couldn't be of more help.

Best,

-AC

AC_H many thanks for taking the time to look into it. Hope to find a suitable one sometime soon.