Hi everyone! I'll greatly appreciate the time and patience put into my newbie questions
My project consists of a refrigeration unit chilling the water of a computer watercooling system (I know...insulation EVERYWHERE to prevent condensation). I will be modifying a small refrigeration unit, originally designed to cool down a laser diode, by installing an evaporator consisting of a 10-15' 1/4" ID long copper tube installed in an insulated 4-5 gallon reservoir with a lid. The unit has a 1/6hp compressor using R134
I would like to have the water down to anywhere beteen 20-30f. Yes, I'll be using an antifreeze mixture. Mind you, the water will have a heatload on it of about 80-90f since it will be cooling down the CPU and the graphics processing unit. Ambient in the room is ususally about 75F.
And now for the questions
1) Is it better to use a TXV or a capillary tube?
2) If I should use a TXV, how do I know which one to get?
A) Adjustability of the evaportor temp would be nice to
fine tune the unit. Is this possible with a TXV?
3) If a capillary tube is better, how do I know how long it should be and what ID?
4) When I construct my evaporator, which is more efficient? Just one long copper tube spiralling around or a grid? By a
grid I'm thinking of 1 long copper tube on each side with several Ts on it connecting to Ts on the other tube. I guess you could say it will look something like this:
5) When torching the pipes together, should I use flux AND solder or just solder?
and last but not least:
6) When I repressurize the system, how do I know what pressures are best on the low and high side, and what do the differance in pressures mean? For example: which gives you a colder evaporator temp, a higher or lower pressure on the low side? Yes, I'll be getting some cheap little R134 gauges just for this project.
[Edited by flybye on 07-17-2004 at 11:29 AM]