SubZ Twins for UFO Duality
One of our members approached me a while back to see if I was interested in assembling a phase change system for him in a case he had fabricated completely out of aluminum; I said "sure".... then he started explaining what he wanted to do :yikes: At first I wasn't sure..... then I saw some pics of the case he had made and that won me over :yup: The thing blew me away with the looks and quality of the build. :thumbs:
http://i8.photobucket.com/albums/a5/...d/DSC00050.jpg
http://i8.photobucket.com/albums/a5/...pty-case-2.jpg
http://i8.photobucket.com/albums/a5/...both-cases.jpg
We agreed on the deal and it wasn't long until 2 large packages arrived at my house. One contained the case with a box inside of it containing enough parts for 2 complete phase change units (except for copper tubing and insulation), plus some extras, the
other contained 2 brand new Danfoss NF11FX compressors. :chit:
Build Specs: (everything X2;))
Danfoss NF11FX 3/8th HP Compressor
Chilly 1 Evap with Jinu braided flex line
"New Style" Chilly 1 mounts
.031 captube
Jinu's condenser
Xtreme Cooling Controller w/LCD (green lcd to match lcd in UFO pc case)
http://i8.photobucket.com/albums/a5/...regs-parts.jpg
At first I figured this would be a simple "assemble the parts and be done" deal...... that was before I got the tape measure out and found out just how much (or how little as it turned out) room I had for this project. Both phase units had to fit inside an area measuring 16"X 17" and the small measurement was front to back where I really could use more room. You can see in the pics with the compressors and condensers sitting in the case, just how much room there is with the front and back case fans..... very little room between the compressor and condenser. :scratch:
http://i8.photobucket.com/albums/a5/...d/P1010004.jpg
I grabbed a bunch of new 1/4" tubing and my trusty tubing benders and set out to try to fit some kind of subcooler coil in this system, after much trial and error (I have a lot of bent 1/4" tubing if anyone needs some ;)), I finally got it done.:thumbs: I am really pleased with the tubing; I felt with the small condensers and general limitation on build room that we really needed a subcooler coil with these units, and I really wanted it in the airflow from the condenser fans if possible. I made a cardboard template that fit in the bottom of the case and set the compressors and condensers in where they had to go and marked the mounting holes for them on the white cardboard. I could then take the cardboard out and use it on the workbench to do all the bending and tubing layout work. This was pretty nerve wracking work for me.... it had to be right the first time and there was very little margin for error..... it also had to look good and I wanted both sides to be as close as possible to each other. Anyway, here is the final tubing layout (with exception of flex lines, which will exit the rear of the accumulators).
http://i8.photobucket.com/albums/a5/...d/layout-1.jpg
http://i8.photobucket.com/albums/a5/...d/layout-2.jpg
http://i8.photobucket.com/albums/a5/...d/layout-3.jpg
I brazed the first unit together today and it's leak testing now, if everything is ok it will be vacuumed tomorrow and maybe an initial charge.
Brazed pics..
http://i8.photobucket.com/albums/a5/...d/brazed-1.jpg
http://i8.photobucket.com/albums/a5/...d/brazed-2.jpg
http://i8.photobucket.com/albums/a5/...d/brazed-3.jpg
Ok..... got the first unit all insulated today and decided to run the load tests. We had a target load of 200w max since Greg is running a dual core X6800 and plans on going to 45nm quad next; Plus the fact that with our limited space we were very marginal on condenser size.;) I was expecting app. -30c at 200 watt, at first that is about what I was getting when I initially charged the unit with r507. I had some r502 here that a friend had given me to try, I knew it had more capacity and would run lower pressure than the r507, so I decided to try it. I charged the unit to around 60psi static pressure with the r502, then started the compressor and tuned to load with propane. It turns out that mix worked very well, I got more capacity and lower temps than with either gas by itself. :D Anyway...... here are the load test results... enjoy:thumbs:
Temps measured at top of evap (runs around 5-6v colder than with probe in base), unit was run at least 30min at each load except for 235 watt, it ran it for at least an hour.
ambient 22c
idle -53.8c
100w -45.6c
150w -42.5c
200w -39.4c
235w -35.4c (never expected it to run this much load, that is max this load tester would do)
http://i8.photobucket.com/albums/a5/...emp-unit-1.jpg
http://i8.photobucket.com/albums/a5/...200w-unit1.jpg
http://i8.photobucket.com/albums/a5/...35w-unit-1.jpg
