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Old 10-07-09, 05:30 PM   #22
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Originally Posted by Xringer View Post
The install manual tells you to ream the end of the tube while it's
pointed downwards (page 17).
Copper is pretty malliable stuff... After you cut off the excess tube from your line set, there may be a bit of a 'burr'. But before you start stuffing things inside the tube, use your flare tool and do a practice flare or two on the line you just cut off. I'd be very surprised if there was any burr after you make a flare.

Originally Posted by Xringer View Post
I would still be worried about getting metal particles inside it.
I was thinking maybe stuff some non-lint fabric up in there,
to block the tube up, and then blow it out with a blast of dry air
from the other end.?.

I have two pipe cutters that I use for cutting copper water tubing.
I think the smaller one might be good for this job. It's pretty sharp.
At work, I use a super fine jeweler's saw and a fixture to cut off
0.141 OD hardline coax cable. That will be my backup method,
if my small tube cutter fails to perform. I can make fixture blocks on my Chinese mill.
Probably will not be an issue.

Originally Posted by Xringer View Post
The manual says "the ideal (or target) vacuum condition is around 10 mmHg abs."
(What does that equal to? Is that 10 Torr? (10 Torr=10,000 Micron?)..

Originally Posted by Xringer View Post
That MasterCool pump does 75 Microns. Will that do the job??
Mastercool Inc., Vacuum Pumps
Should work just great... If you have a micron gauge, you'll know for sure it's working great.

But remember to change the vacuum pump oil just before you do a pump-down. By design, vacuum pump oil absorbs atmospheric water.

Even though your vacuum pump has never been used, it's been sitting and absorbing atmospheric water. Change the oil.

My friend, Bruce-the-Pirate bought a two gallon jug of vacuum oil for some kind of low price. Big mistake. Every time he opens the jug, he's introducing more atmospheric water. Personally I would throw the jug away. But he wears an eye patch and will probably use it anyway.

Buy a small one-shot or two-shot bottle and don't open it until you're ready to use it.

I bought a small plastic two-shot bottle, used half of it, capped the bottle tightly back up and left it on the shelf for a couple of weeks. Now the sides are all caved in because the oil has been sucking the moisture out of the air that was trapped inside the bottle. Pretty amazing. You want that kind of oil to be working for you!



P.S.: And remember, I'm not an HVAC technician. In fact, I'm just barely a hacker.

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