Quote:
Originally Posted by AirConditioner
Not trying to offend you or anything, but are you sure you sealed the threads properly? (Maybe there is a special way it needs to be done for such high pressure?) I thought threaded flare connections were pretty standard in A/C stuff? I even found access valves for sale with 1/8" NPT threads. (still can't post a link)
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Well, it's clear that you are too hard-headed to take advice, but hey.. we can still be friends.
In terms of sealing it properly, I'm pretty sure I did everything that science or magic could provide... and it still leaked.
Just remember the key words,
"high pressure", "
severe temperature cycling" and "
relentless vibration". That is what makes refrigeration different, that's why brazing is superior.
Quote:
Originally Posted by AirConditioner
This is one of the biggest reasons I don't want to braze. Eventually I'd like to braze a finished "contraption", but I would much prefer to thread my test system so that I can change parts easier. I also want to experiment with a thermal expansion valve, it might take more than one configuration before I'm happy.
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Well, OK... as long as you realize the temporary nature of your 1st project.
Quote:
Originally Posted by AirConditioner
I'd really be cranky if I spent $50+ on a heat exchanger, brazed it in, and then changed my mind about how I want this to work. (or ruined it in the process!)
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OK, now we're getting to the heart of the issue. You aren't confidant of your skill level. That's quite natural, and prudent. So, the secret is to get some tools, some lengths of differing diameter copper tubing, maybe some kind of dissimilar metal also to practice on.
Practice off and on for a few days until you get the feel of how the process works.
That Sil-FosŪ 5 is really wonderful stuff. You need proper heat, clean fittings and a bit of sensitivity to the process, and you will succeed.
Proper heat is critical, they say "cherry red"... you really need to see it, and then you will understand what that lovely color means.
Try brazing tube-to-tube... You'll need to flare one of the tubes a bit and the other tube will go inside, doesn't need to be a tight fit, the Sil-FosŪ 5 will flow around and make everything pretty... just gotta get to "cherry red".
Also try brazing smaller tube to larger tube, use the 'pinch' trick and braze as you usually would.
Quote:
Originally Posted by AirConditioner
I did read here about somebody's experience with compression fittings, and I can see why they might fail. I'm just not sure why threads would leak? I also wanted to store my R22 charge in a (new) paintball CO2 tank, which is threaded for 3/8" flare threads. How would I store the R22 if I can't seal the threads?
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I store mine in empty green camping propane bottles which I have vacuumed to within an inch of their life.
I made a simple tool from an extra propane torch that I modified. If I didn't include that in the links, do a search on this site.
Quote:
Originally Posted by AirConditioner
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Looks like a reasonable HX. But if you're still asking if it's big enough, you didn't look through the Brazed Plate manuals I suggested...
So, if you don't want to do your own research, my friend, you'll just have to guess.
By the way, if (when) the threaded connectors leak, you might be able to braze to the threaded area on the HX. It won't be as easy as finding a HX with sweat fittings.
Oh, and here's one that someone did all kinds of bizarre things to... Make him a too-low offer, see what happens.
Alfa Laval CB26 24H 1" NPT Brazed Plate Heat Exchanger P N 3080079604 | eBay
And try this guy, you can get your threaded connector and your sweat fitting in most any size in the world...
http://www.ebay.com/itm/Stainless-St...item906f6f3789
Best of luck,
-AC