What expansion valve?

[hatemi]

I have seen many of you use some sort of expansionvalves in various systems so I thought I might try one as well. I remember Berkut modding some TEV to manually adjustable XV and he also used some other valve in his small DD project.

Now the problem is that I dont know what valve should I get. I dont know what kind of valves works best, and am quite intimidated to just order any bacause I dont want to waste my money on something I cant use...

Is there any specific models I should look for in the catalogues? I would prefer manually adjustable valves but automatic valves should work as well.

[JSU]

I think the ones you need are 1/8ton - 1/4 or 1/3 or something aroundthere. The one that berkut is using is a cpev constant pressure expansion valve. Those are the best I think seing as they have finer adjustment then regular txv's. Btw what kind of system is this on?

[HawainPanda]

on teampuss.com, look on the 3rd and 4th pages i think of hallowen's topic of the 2 stage cascades, runmc and some others posted lots of links to catalogues

[HawainPanda]

and..yeah, u have to get the lowest rated...but runmc used a i think 1/4ton and it worked really nice

[RaVeN155]

Yes CPEV's are very cool, i use it in my systems and it work's great. You can set suction pressure that you want.

They are quite small also :)

[JSU]

Actualy the 1/4ton worked ok for a cascade. The problem with them even on a cascade is that they "hunt" meaning it gets to its limit cold wise then heats up a bit then gets down to its coldest etc.

[hallowen]

It sure is a LOT easier to adjust for different Pressures/Loads Though.!:D

Here's what I used on the First Stage of my Cascade, It is an ALCO 1/4 ton TXV:

http://hallowen.freehosting.net/txv1.jpg
http://hallowen.freehosting.net/txv2.jpg

On the Second Stage, I used a PARKER A-2 CPEV:

http://hallowen.freehosting.net/hq5pev.jpg

[JSU]

b/c your realy good with captube sizings.... for the rest of us mortals we dont like draining our system adjusting the cap tube vacuuming and recharging over and over again.......

[HawainPanda]

i dunno, its not really that often that u have to change it though, i mean sure if u get a new rig u can adjust for the best perf, but if u make ur heatload high and make ur temps as low as u can, changing it will only be maybe a couple degrees higher or lower, and once u get down to super cooling, u mite get a couple mhz more

[hallowen]

HawainPanda

A Few Degrees Lower, A Few More MHz...........:stick:

Every Little Bit Helps When You Are XTREME!:rocker:

[chilly1]

Actually a cpev will allow you to optimize teh temperaure for every load say you are running superpi and need more mhz the processor is under less load than running 3dmark so you can drop the pressure and get move volts adn higher mhz then you run 3dmark 03 and need very high capacity to complete the run you got it just raise the suction pressure etc. It takes a little time to get the feel of your system but eventually you can dial it in for each application you run. It would be nice if we could come up with a temperature optimazation routine and I am collecting stats to get there one day.

[JSU]

The parker a-2 is rated at 1-2 tons..... is that the range we are looking for on the low side of a cascade?????

[hatemi]

It would be a small DD system with R290 as refridgerant...

[saratoga]

How much does a CPEV cost?

[JSU]

I think 50~

[RaVeN155]

Mine (berkut use the same) cost 20, but ... it is made in Poland so propably Parker's will be better ;)

[JSU]

i think the parker goes from 5hg to 90psi