2 compressors 1 evap but no cascade

[pocketbikeuk]

Would it be possible to set 2 compressors linked to a evap with 2 chambers both compressors being the same size and setup but set them for 100w each so in my theory they could handle a combined 200w and would be running in a good vacuum so giving some good temps ie propane -60 just an idea an info on this or thoughts?

[Nyx]

-40 in each evap. would not give u -60. It will only mean u can hold more load and it will be a waste as the cpu does not give out so much load as u imagine. One evap is sufficient. Build 2 DD one for cpu and one for GPU u would be much happier. Than going through so much trouble building a 2 chamber evap.

[Gray Mole]

Actually you could.

If each evap 'chamber' was tune for around 100w, you'd be able to tune each one a lot colder.

It would take some custom work, and tuning each system would be interesting, but the results I think would be surprisingly good.

Looking at Johann's chiller, using 2 compressors running independently to the same HX coil brazed together gave amazing results.

The only very difficult part is making the evap really, as it's got to be large enough to accomodate both systems, and give enough evap volume to each for efficient evaporation.

Interesting thought, I think the first thing you need to do is to design the evap so it will stil be workable for cpu mounting, but will do what it needs to do.

Gray

[pocketbikeuk]

-40 in each evap. would not give u -60. It will only mean u can hold more load and it will be a waste as the cpu does not give out so much load as u imagine. One evap is sufficient. Build 2 DD one for cpu and one for GPU u would be much happier. Than going through so much trouble building a 2 chamber evap.

wot i meant was by using a longer cap tube i would also be running the evap in a vacuum therfor being able to reach a lower temp ie -60 and as i am able to get hold of loads of small compressors ie 1/8th i was thinking of ways to cool 200w with decent temps using 2 small compressors without the complexity of a cascade if that makes sense? would it work? chilly?

so how much heat does a 3.6 ghz p4 put out at 5ghz or a overclocked fx57 i think 200w is possible with these processors this reply is for nyx but any info welcome as always will design a evap prob a maze design of some sort

[pocketbikeuk]

Actually you could.

If each evap 'chamber' was tune for around 100w, you'd be able to tune each one a lot colder.

It would take some custom work, and tuning each system would be interesting, but the results I think would be surprisingly good.

Looking at Johann's chiller, using 2 compressors running independently to the same HX coil brazed together gave amazing results.

The only very difficult part is making the evap really, as it's got to be large enough to accomodate both systems, and give enough evap volume to each for efficient evaporation.

Interesting thought, I think the first thing you need to do is to design the evap so it will stil be workable for cpu mounting, but will do what it needs to do.

Gray

hey gray mole a bit off topic but as u are in the uk just wondered if u had any old supplies lyin about that u wanted to get rid of or if u knew of any other good uk suppliers that arent in the forum and cheers for ur thoughts

[the_new_guy]

why not just run the compressors in parallel like the danfoss twins

[pocketbikeuk]

why not just run the compressors in parallel like the danfoss twins
complexity again not sure on how to do it and are there problems with oil return and things like that im quite new at this but have been reading quite a bit if you can post some pics or link to some info on running comresors in parrallel then i may consider it? cheers for your thoughts

[the_new_guy]

you will have to drill the compressors and put a oil balancer line or what ever you call it to keep the same amount of oil in both the compressors

[Nyx]

Just want to ask you something have you build a working DD first. If you were to jump into something like that you will only find yourself troubleshooting it for weeks. Building it is easy troubleshooting it is the ultimate.

[pocketbikeuk]

you will have to drill the compressors and put a oil balancer line or what ever you call it to keep the same amount of oil in both the compressors
once again complexity good idea too much for a noob. just a thought i could run a foot or so of each of the suction lines round the discharge line of each condenser before the filters so i could subcool them more baisically making a hx on each one would this help at all? or just put more heat into each compressor making the need for larger condensers or more powerfull fans making the whole idea pointless?

[pocketbikeuk]

Just want to ask you something have you build a working DD first. If you were to jump into something like that you will only find yourself troubleshooting it for weeks. Building it is easy troubleshooting it is the ultimate.
yeah built a workin one by stripping a old dehumidifier and brazing a cap evap on it although i had no flexline for the suction line so it was kinda hard mouting it and i only had r134a so only got -22c unloaded this was on a 1/12th compressor which wouldnt handle the load of my a64 3200 at 2850 and 1.76v so looking at building a new one i have a 3/8th comp and a 1/4 but also loads of little 1/8th im currently building a system with the 3/8 but looking to use these little ones to get good results rather than having loads of poor capicity systems. cheers

[Gray Mole]

Hey mate, I have bits and bobs I keep around, and if you need something specifically and can't find it I'm happy to help if I can, but there's some decent suppliers out there.

BES here in the UK does a lot of the basic stuff for insulation and tubing and stuff, all online.

Dean and Wood is good if you can get to them, same for HRP. I deal with both and they've been fine.

Otherwise, Ebay is a great place to find stuff, just watch the prices, sometimes you end up paying more than the trade guys will sell it to you for.

Cheers

Gray

[Nyx]

Here is something to think about. Why not use a bigger compressor and have 2 cap tubes running into one evap which has 2 chambers. Wouldnt it be just the same. If a dual evap system can hold a load of a cpu and gpu why not change it this way and u can save up one compressor. Gray do you agree on this. I mean a dual evap system could do it why not make full use of it for a design this way. You can combine the Suction line and save cost on getting one more flex hose.

[Gray Mole]

To be honest I doubt you'd really gain anything running a dual chamber evap as you'd lose what you gain by runnign a single compressor. To really prove that theory someone would have to build it and compare results side by side with a similar compressor just running a normal evap, but I think it would really just do about the same unless you had a very efficient evaporator.

I'm not the biggest fan of dual evap systems in single stage at the best of times, though it you've got a powerful enough compressor you can make it work well, it's just you share capacity and your temps suffer.

In a GPU system it's not so bad because it's so much easier to 'waterproof' your cards at -20 than at -50 but if max performance is what you're after then a compressor per evap is what you want.

This proposed system interests me a lot though. Using the power of 2 compressors to cool a single evap in separated systems I don't think has been done before, and it has a lot of potential.

I think that if you took a 2" round block, and machined each side to 3 steps (stepper evap) and used each side for one system you'd have it sorted, and it wouldn't have to be too expensive to machine. I don't really have the time to photochop a pic of what's in my head atm, but it would have to somewhat long to allow room to make the chambers big enough to be efficient. The greatest challenge in that would be ensuring no seepage from one side to the other which wouldn't be easy.

Otherwise a dual maze square block would be pretty easy to make, just a drill press job would be enough, and you could braze a separate plate on each one and there'd be no chance of seepage.

Maybe one day I'll have time and try it, cos a 10cc or so Danfoss job tuned to 200w or so can keep an evap at around -40 under 150w load with the right gas and tuning so tuning each one to 100w and -60 would give you close to Autocascade performance without all the headaches of running one as it would probably be able to run each system into vacuum under load with no problems.

mmm

I say go for it, and make sure you post your results :D


Gray

[pocketbikeuk]

To be honest I doubt you'd really gain anything running a dual chamber evap as you'd lose what you gain by runnign a single compressor. To really prove that theory someone would have to build it and compare results side by side with a similar compressor just running a normal evap, but I think it would really just do about the same unless you had a very efficient evaporator.

I'm not the biggest fan of dual evap systems in single stage at the best of times, though it you've got a powerful enough compressor you can make it work well, it's just you share capacity and your temps suffer.

In a GPU system it's not so bad because it's so much easier to 'waterproof' your cards at -20 than at -50 but if max performance is what you're after then a compressor per evap is what you want.

This proposed system interests me a lot though. Using the power of 2 compressors to cool a single evap in separated systems I don't think has been done before, and it has a lot of potential.

I think that if you took a 2" round block, and machined each side to 3 steps (stepper evap) and used each side for one system you'd have it sorted, and it wouldn't have to be too expensive to machine. I don't really have the time to photochop a pic of what's in my head atm, but it would have to somewhat long to allow room to make the chambers big enough to be efficient. The greatest challenge in that would be ensuring no seepage from one side to the other which wouldn't be easy.

Otherwise a dual maze square block would be pretty easy to make, just a drill press job would be enough, and you could braze a separate plate on each one and there'd be no chance of seepage.

Maybe one day I'll have time and try it, cos a 10cc or so Danfoss job tuned to 200w or so can keep an evap at around -40 under 150w load with the right gas and tuning so tuning each one to 100w and -60 would give you close to Autocascade performance without all the headaches of running one as it would probably be able to run each system into vacuum under load with no problems.

mmm

I say go for it, and make sure you post your results :D


Gray

cool il keep you posted hopefully will see some good results without having to cascade il prob run r22 or r290 or both to see how it goes?