Prebuild Questions

[SilverVenom]

Hey all, I just wanted to ask a few questions to get me off to the right start with building a water chiller. After reading on these forums and asking a few local friends about how they went about building their water chillers, I felt that I would build one to compliment my new X-Mas rig. My current idea is to create some sort of box/tower on wheels to house the unit. For the water loop I would have a styrofoam box, but I would encase it with plastic to prevent it from falling apart over time. I would use a 110AC submersable pump here, but I have no idea what pump can take the low temps..any help there would be great. For the tubing, I would like to use PrimoFlex 1/2" ID. Will this also hold up to the low temps with out cracking? Then as for important stuff... For the compressor I actually wanted to use 2 identical compressors and put both of their evaporators in the styrofoam box, not in a cascade because i'm not sure I could do that properly... I don't know exactly how much room this will take up when you factor in all the parts, but I'll let you help me out with the specifics. As for sources, I was going to contact my A/C guy because he takes away all the old refrigrators/dehumidifers etc. when he installs a new one, so i'll see if he will let me snag one or two. I would prefer to stay away from buying them online due to shipping costs. I would really like to try to use dehumidifers because everything was made to be compact and I wouldn't have to much work to mod it. I was also thinking about doing the drinking fountain mod that i've read about here, but I don't know if that will offer low enough temps to justify something like that sitting in the corner of my room. Any input really help. Thanks for your help, - Peter.

[SilverVenom]

I was looking over the Liquid Frostbyte thread..again..and for the space saving design liked the pipe in pipe heat exchanger idea. I was wondering if it took longer for the temps to be pulled down than using a resevoir. Also where could I find one online or what chain of stores might have one? Thanks, - Peter.

[RussC]

You can buy them pre-made. Look online at United Refrigeration:
http://www.uri.com

or Jonhstone. UR will have a PDF of their catalog opnline. Download it. The water cooled heat exchangers is what you want, page 174.

RussC


I was looking over the Liquid Frostbyte thread..again..and for the space saving design liked the pipe in pipe heat exchanger idea. I was wondering if it took longer for the temps to be pulled down than using a resevoir. Also where could I find one online or what chain of stores might have one? Thanks, - Peter.

[SilverVenom]

Something along the lines of this? http://www.uri.com/is-bin/INTERSHOP.enfinity/WFS/PrcTransaction/en_US/-/USD/ViewOfferDetail-Start;pgid=okGsEEGSDDgAAAEEBNygUMOl0000zAu3w3qO?Pr oductUUID=h8asEEGSqKcAAAEEipegUMBh&CatalogCategoryID=xwKsEEGSzqAAAAEFBvqRn1mQ Also, if my compressor is running R404a gas, with a ~290W heat load, what do you think would be a good cap. length? Thanks, - Peter.

[RussC]

Yup, thats one, plus the others there.
Depends on compressor size. The cap tube will come with chart for lengths. Look over in the Vapor Phase Change section for more on cap tube length also.

RussC


Something along the lines of this? http://www.uri.com/is-bin/INTERSHOP.enfinity/WFS/PrcTransaction/en_US/-/USD/ViewOfferDetail-Start;pgid=okGsEEGSDDgAAAEEBNygUMOl0000zAu3w3qO?Pr oductUUID=h8asEEGSqKcAAAEEipegUMBh&CatalogCategoryID=xwKsEEGSzqAAAAEFBvqRn1mQ Also, if my compressor is running R404a gas, with a ~290W heat load, what do you think would be a good cap. length? Thanks, - Peter.

[SilverVenom]

I looked around on the Vapor change cooling section and found http://www.xtremesystems.org/forums/showthread.php?t=29694 that... but if I use that forumula, then I end up negative cap tube? :confused: Obviously that isn't possable, so I posted but no reply for the past couple of days... Any ideas?

[RussC]

Ok,
What refrigerant and what size compressor? Then look at this chart from Supco on page 31 of their HVAC catalog:
Supco HVAC catalog PDF (http://www.supco.com/images/1%20HVAC%20Section.pdf)

You may want to add some inches to the low temp #s there, as you may want lower than -10F evap temps,

Thats all you need,
RussC




I looked around on the Vapor change cooling section and found http://www.xtremesystems.org/forums/showthread.php?t=29694 that... but if I use that forumula, then I end up negative cap tube? :confused: Obviously that isn't possable, so I posted but no reply for the past couple of days... Any ideas?

[SilverVenom]

Do you mean the sinlge feed caps or double? Just making sure..well, my compressor is going to be 3/4th HP R404a, so... 39"? Sounds long :stick: , but i'll give it a shot. Should be getting all the stuff I need within the next week, but i'll be putting it together over X-mas. Thanks for your input Russ, - Peter.

[RussC]

I guess single, your runing a single compressor, right?

The cap tube is a game of pressure vs capacity. You can go longer on the cap and get lower temps, but you loose capacity. If your compressor doesn't have the capacity to cool your load, but the cap to long, higher temps. Longer cap only works for lower temps if your compressor and condender are oversized for the load. Then the longer cap is properly fed with refrigerant and the capacity loss at the compressor is OK.

RussC


Do you mean the sinlge feed caps or double? Just making sure..well, my compressor is going to be 3/4th HP R404a, so... 39"? Sounds long :stick: , but i'll give it a shot. Should be getting all the stuff I need within the next week, but i'll be putting it together over X-mas. Thanks for your input Russ, - Peter.