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Old 02-13-12, 07:33 AM   #16
Xringer
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Quote:
Originally Posted by TomWS View Post
Let me see if I understand.

Even if I use compressed atmospheric air (not specially dried) to pressure test the lines, since there is so little volume in the linesets, I won't be introducing a total amount of H2O that is outside of specification?

Further, if I then vacuum the lines to 500 microns (or, at least, below the vapor pressure of water), then the bulk of even that limited amount of water will be removed from the linesets?

Tom
That's correct.
Since this is line-set only, you will not be contaminating filters etc inside the ODU.

But, I would not use air right from your garage air compressor, it's loaded with water.

And, do not try to use C02. It's very reactive when heated. If you added
a little too much, your lineset could be exposed to unsafe pressures. (900+ PSI).

Nitrogen from your local Paintball shop will be at 3,000 PSI..
And a small tank will run low on pressure pretty quick.
I once had to go back for a refill in the middle of testing.

I had a hacked connection to get 1/4" SAE at first,

But got a spare manifold fitting to use on my PB valve.
You can find a PB extension rig on-line or at a PB shop for about $20.


If you don't want to buy all that stuff, they sell R410A on Ebay.
You could use that for a test gas real easy..

Smaller cans too..

It is important to get all the moisture out of the line set, so you are likely
to need some vac extra pump oil to get that job done.
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