Try Alaska Copper
http://www.alaskancopper.com/cuni/pd...ess_tubing.pdf They have a
90/10 copper/nickel tube that is probably the best material for exposed
condensers.

You need to do a lot of research to roll your own A/C condenser. The tube
size and length is a compromise between pressure drop, heat transfer and oil
movement. The surface area has to be sufficient to transfer enough heat.
If it is to long and small diameter the pressure drop will be to high. If
it is short and large diameter the refrigerant moves to slow so the oil will
drop out and be trapped in the condenser which will starve the compressor of
lubrication.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"MarshallE" wrote in message
...
Hi,

What is the normal metal tubing used for keel coolers and how long should
it
last?

I am having a heck of a time locating a seawater condenser and have about
decided to make from scratch.

I want to A/C using 5 tons for my boat.

thanks for help and opinions,

Marshall