Glycol chiller build

Hi everyone
I was wondering if you could share/ advise me. I’ve used the search bar and I don’t find the answers Im looking for.

I have some 3"x 20" spools on the way, but now id rather have them jacketed.
With them being on the way I was thinking I can get the local fab shop to jacket them for me.

I was wondering if anyone could advise on what thickness steel I should jacket with? I want to run cold glycol through it.

I have a mate who does industrial coolers and heaters so we gonna Frankenstein a chiller up for me out of a 24k split unit. Will it reach -20-30?

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Hi,
3" column correct? for the 4" tube forming the jacket .065 is a good thickness.

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Tempted to edit this for you…

As far as how cold your diy chiller will get, that depends mostly on the refrigerant. Assuming 24k Btu, it seems big enough that your heat load should have little effect on ultimate temp.

@SidViscous more qualified to address what that ultimate temp might be (but is gonna need more detail).

Edit: of course, I could be wrong on that heat load…for all I know you’re ALSO trying to cool a 300lb solvent tank & your freeze dryer with that chiller hack :nerd_face:

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It’ll probably get that low. If you post the specs to the compressor and what refrigerant you’re running I can tell you what the BTU output will be at -30.

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Ok so then we only need 1/2" all round worth of jacket depth?

.065 inches = 1.6mm correct

Does anyone have a technical drawing they can share that I can send to the fab shop?

Who knows this might turn to a business for me here in South Africa… we lack descent extraction equipment. not common here, so no craigs list etc

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I can dm you one in a bit, not too complicated. What size fluid connections do you want?

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You’ll want to know how to hydro-test. There is information here on the subject.

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Well, I’m going to make my own glycol chiller so ill use a submersible pump and probably go with a 20mm (3/4") hose for the transfer of fluids.

do you want pipe threads?

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Hi Sousvide

So finally getting round to this build again.

Im planning on going with a 18K/24K Btu R22 unit charged with r134.

I am hoping to be able to use this chiller to chill my columns down to a good -20/-30? Instead of having to lay them in Dry ice each time.

I also will be adding a N assist on this. so I dont gotta move tanks in and out of water baths.

Any one have a drawing of a 6" jacketed splatter platter that I can circulate cold/warm through? for engineers to make up for me?

Did you get your spools made up yet?

I would not advise 134a (honestly, it’s kind of a lousy refrigerant). To hit -20f (which is also not as cold as you want to be) your evaporator will be under vacuum pretty thoroughly and any leak on the low side will ruin your system. The low operating pressure paired up with an r22 compressor kind of makes sense but it’s still not going to be awesome.

Where are you located? I don’t have a drawing of a jacketed cap but I could probably find a link if you’re stateside. Personally, I think DX makes more sense for DIY than running an intermediary HX fluid unless mobility is a big thing for you.

I know I won’t hit numbers like -40 with a DIY solution but I was hoping this could help me chill my material? what temp do you think is acheivable?

I’m located in South Africa, so chillers are put of the question for my small operation. I mean my max volume of material per run is like 1000g±.

Sorry what is DX and HX, please excuse my ignorance.

So we are now looking at R404 and a low vac compressor to do the job. I wanna hit -40deg C.
lets see if my wizard can do it.

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Yes this is a better approach. DX is “direct exchange” meaning the refrigerant actually goes through the jacket. HX is short hand for heat exchanger.

Just make sure the jacket and spool are rated for the standstill pressure of the system, if the spool isn’t thick enough it’ll collapse when the system is turned off.

The other thing I’d recommend is doing your best to minimize the compression ratio by managing the condenser temperature. The reason so many of these chinese r404a chillers fail is that they are compressing from ~ 10 psia up to like 350 psia (35:1 CR) because the condensers are way undersized and they stay really hot. If water is very available to you, you can do a water cooled condenser which will make your compressor live a lot longer. By reducing the condenser temp to 60-70f your discharge pressure drops from 350 to ~130 psia.

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Genius

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Also has the added benefit of making your chiller more compact (I use plate HXs for this) and allowing you to pipe the heat out of your room.

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So I have actually made some progress on this after it being put on the back burner.

We have used a 12k BTU console unit. stripped the cold side and put it into a tub with some glycol/water 50/50.
We managed to get to -15c on first attempt, getting the gas to as low as we could.

Friday we will fill with 404 and will make our own coils with extra expansion valves.

I want to hit -40. Ill post pics of our trials.

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