Love to see an AC split to -40C chiller hack
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So, I’m looking on eBay for what the absolute most common cheap ass 1-2hp split system is but they’re almost all r410 which makes a pretty lousy low temp refrigerant and is awful for DX applications because of the high pressures. Also not very DIY friendly. Anyone have any votes on what system to base this thing off of?
I’m thinking a two stage intercooler-style system running r404a would be ideal but I don’t want to spec compressors that might not be readily available. Also not sure if people would prefer an air cooled or water cooled condenser (I love water cooling but this is supposed to be a redneck chiller).
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Seems like a TRS-21, a 5lb recovery tank, and an orifice for the collection base are all that’s really needed to cool with r600.
Oh, And some redneck water cooling on the recovery tank (garden hose). 
Edit: gauges and prv wouldn’t hurt…
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Spoon request: where does one find the maths for figuring out things like refrigerant load or orifice sizing?
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Yes but we want something more extreme and unnecessary! Or maybe I’m just bored
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Extreme and unnecessary? Sounds like a blast.
We need a 2ton refrigeration system that uses a bonfire for cooling 
Edit: what are our refrigerant options?!?
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So for TXVs I always just go to Sporlan’s literature. I honestly have never designed a system using a fixed orifice because usually if it’s worth the time to build something it’s worth the $60 for a real TXV. Also, I’ve had very poor results with the tech support at sporlan, the last two times I called and spoke with an application engineer they undersized the valve. But their lit was spot on.
Here’s the bulletin that I pull nearly everything from: 10-9.pdf (1.2 MB)
It’s a bit of a read but it’s very very comprehensive
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Thermal expansion valve. I’ve learned something. Quitting time!!! 
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So if we want crazy extreme we’d have to use ammonia because it’s awesome and horrible all at the same time. But if we really want bonfire powered, some sort of boron salt like they use in adsorption chillers is probably the trick
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what about adding more moving parts?
Steam turbines can be appropriately awe inspiring…
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Have you looked at using suva 95 for the second stage refrigerant? Works a treat!
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I was just reading about 508b as an improved r23 mix last night. I love r23 and I also love aezetropic refrigerant mixes. Sounds like a winner in my book
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I dont think I should start a whole new topic but- I want to pull a vac on a 6x6 fully jacketed spool for insulation. Anyone have experience? Is pulling a full vac likely to make it implode?
Little searching should reveal at least a dozen examples of folks pulling vac on their 6” jacketed material columns. Only implosions you’ll find mentioned would be Bizzy columns with liqCO2 run through them…full vac is 15psi. LiqCO2 runs 70ish
Edit: check this… Imploded Materials Column 6x48 BVV
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So now I have an extra large yeti cup
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I looked at the link and that was the spool imploding, Im more worried about the thin jacket. I just happened to get this thing but Id rather it hold temp than me manipulating it with water flowing.
You need translation?
I said; try as you might, you ain’t gonna find anyone reporting a problem sucking on these damn things.
If you want to collapse them, you will have to try harder…
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Well translation? are you being a smart!@# The link you provided showed a collapsed train car from draining water. Sorry for asking to be safer. I guess I shouldnt have used the search engine to find this thread.
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You asked. I said it wasn’t a problem.
You asked for clarification. Not sure how to be more clear.
If you want it to collapse after you pull vac on the jacket you are going to have to beat it with a stick.
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