R507/R402/R410 as 2nd stage gas??

[andre X_X]

hi, currently i have a CO2 cascade now, well its not so good but not that bad too :p:.... idling at -69c to -72c and arround -55c to -59c on 250w.

well, i've seeing some builders here with their R507/R410/R402 single stager that almost and might be beaten my 2stager CO2 so i'd like to know what kind of temp if i put those gas on my 2nd stage?

its just so damn hard to get any gas colder than CO2 here in my country :(

[n00b 0f l337]

I think you'd be rare to see -55C to -59C at that load on a single, even with r402a. I think you'd gain some capacity, but probably not much in temps, probably lose a few degrees.

[[XC] gomeler]

Ethane or Ethylene? R23 or R14? Anything at all?

[n00b 0f l337]

R14? Gom, he can't run a 400psi high side :P

[[XC] gomeler]

R14? Gom, he can't run a 400psi high side :P

Could run R507 in 1st stage, R744 in 2nd stage, R14 in 3rd stage. Just trying to think outside the box, I know how much trouble they have at getting LN2 :shrug:

[tiborrr]

R170 should be ideal if first stage is strong & cold enough. Care to post pictures of your cascade please?

[andre X_X]

thx for the answer guys... then its more about capacity....
@tiborr: you can see my sig for worklog :)

[Raadster]

your link for your worklog doesn't seem to work.

[kayl]

if you used say r134a in the first it might be ok using r410 in the secondstange. If the first stage is too cold the secondstage high side pressure will be really low, like under 100psi and there wont be much flow in the system in the second stage.
We must remember the only reason we run cascade stages is to allow each stage to condense at a safe pressure, there will be an ideal condensing pressure/temperature for each refrigerant where there is still enough head pressure in the system, and enough refrigerant condensing into a liquid and not as a gas.

Have your tried BOC gas?? they should have ethane and ethylene.

[n00b 0f l337]

His link doesn't have the www. before xtremesystems, add it and you get the link :)