Quote:
Originally Posted by Xringer
Please note that cap tube is not made from soft copper like the rest of the tubing is, and it will not bend easily like soft copper.
Wow.. That's good to know. I had figured (based on looks) that the cap tube was going to be very bendable stuff.. Allowing me to reposition a coil easily..
|
Well, the cap tube will bend but not so easily.
Just to give you an idea, I was thinking about sizing my own cap tube (
there are tables for doing such a thing) and I asked a refrig. man if it was necessary to de-burr a cut cap tube, and he told me that everybody he knows just makes a file 'nick' (which I took to mean a very small groove) in the tube where they want a cut, and they bend the tubing a bit, and it will snap off without a burr. Just imagine how soft copper would behave if you made a small nick in the tube and bent it slightly? Different stuff.
I have bent cap tubing a little bit, to make it fit up, but I was very careful and aware of the limitations when I was doing it.
Quote:
Originally Posted by Xringer
What's the idea behind a dual cap tube setup??
|
I've even seen photos of a quad tube setup. I think there is a limit to how much HVAC energy can be effectively handled using a single cap tube. That's why the multi-tube setups.
The advantages of using cap tubes is that they work, are extremely reliable and they are cheap. There's another kind of metering device called the
Thermal expansion valve or TXV or TX valve.
They have the advantage of being adjustable, so you can dial in exactly the amount of refrigerant that will pass through. They also have the advantage of having a feedback loop built in so they can keep the behavior of the device constant under varying conditions.
I haven't used a TXP yet, but
I bought on off of ebay for about $14. It's a Danfoss. Turns out that it uses various inserts to give it different ranges of refrigeration capacity. The insert alone cost me more than the valve. I'm keeping it in my kit box to experiment with. I priced one of them at the local HVAC supply shops and it was around $100. Ebay good.
Quote:
Originally Posted by Xringer
In the summer of 1973, I found a 'blem' 18,000 BTU Chrysler Air Temp
at a local strip mall. $200 and it was in the trunk of my LeMans..
In the spring of 2007, my wife fired it up, forgetting to remove the snow cover..
After that, the old power hog didn't work so well.
|
I don't know if you have discarded this unit yet, but if you still have it and plan to do some HVAC experimenting, the compressor is probably fried. However the refrigerant could possibly still be good, as well as the condenser & evaporator cores.
Also your Kenmore 18,000 (Ton & a half) would be great to experiment with. However, even though it's a bit on the large side, the Freon is useful (you probably have 1.5 to 2 pounds in there) and the condenser and evaporator cores might be interesting to pair with a smaller compressor, like maybe 400 to 600 watts.
Also, if you're thinking about doing any kind of Ground Source heating or cooling experiments, if the rule of thumb that works for Western Oregon were to work for Mass, 18,000 BTU's would call for 300 feet of borehole or something like 200 feet of trench. That's a lot of earth moving. But a 600 watt unit would only need half as much digging and a 400 watt would need a third. Of course the amount of heat that they'd move is smaller by the same fraction.
Best Regards,
-AC_Hacker
%%%%%%%