Chiller Hack (DIY)


There are 220-240 volt 15k-30k btu used ac’s cheap on craigslist. anyone here use a window unit to make a chiller for their rotovap? a 1hp water chiller is about 1500 bucks online with a heat removing capacity of about 7k btu/hr and a 1.5hp chiller is about 10.5k btu/hr.

I would imagine a person could build a large capacity chiller for under 500 bucks easily enough.

1 Refrigeration Ton = 12,000 BTU

How this relates to HP does cause a lot of confusion. It is true many people equate that 1 HP = 1 Ton, and this isn’t accurate.

Basically the colder you operate, or the lower your evaporator temperature on your refrigeration system, the lower your BTU/Hr Capacity is. Because of this it is impossible to directly correlate HP to Refrigeration Ton.

for example:

If you have a 5 HP refrigeration system operating under typical AC conditions (45F ET/130F CT/95F AMB), it will remove 56,000 BTU/HR, or 4.71 Refrigeration Tons.

This same 5 HP refrigeration system operating on a Brewery Chiller System (20F ET/120F CT/95F AMB) will remove 35,700 BTU/HR, or 2.98 Refrigeration tons.

So for an Air Conditioning project the 5 HP system has a 4.7 ton capacity, but for a lower temperature chiller application it will deliver less than 3 tons capacity.



Some more stuff from IG I’ve seen



Around here the 18k btu 7 to 8 amp draw 220v 10 eer rated used AC’s can be had for 100 bucks. Another 100 bucks in some plywood, a cooler, casters and hardware. then a 50 dollar 30-40 psi external self priming ( don’t want to use a submersible pump) 2gpm pump some tubing, pipe insulation then wire in a tstat of my own to remove the AC’s internal tstat

Mini Split / Ductless AC glycol chiller:



What model pump



How would I get on down to -30 and keep it ?



I need one that will do 100,000 btu

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Oh sick thx



What’s the AC temp limited to? Couple Google articles say 16c is the low operating range?



I can’t remember off the top of my head what the low side operates at back in the overclocking days we built custom on-chip dies. The window AC unit would pump freon to the chip direct on die and it would get down around -30 to -40 we also swapped VR 410 with something else I can’t remember maybe 134.

This is mainly for a rotovap or distillation condenser not for creating ultra-low temperatures like a Cascade system would

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Nice, I’m hoping to build myself a roto but falling film style. See if I can get 5-8LPH or something for $700 instead of $4000



Once you manually wire up the compressor hey DIY glycol chiller can get well below freezing

I’m probably just going to get myself a 2000 rodeo and build my own glycol chiller for it out of a window AC. A 2-ton window AC will have some serious fucking heat removal power. A 2-ton window AC could net you performance equivalent a 2-ton window AC could net you performance equivalent to maybe two and a half horsepower chiller

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What about running a few of them in tandem? There’s a dozen 5-8k btu ones up for grabs for $50 on Craigslist



Keep an eye out I’ve seen a couple two ton 220v units for less than a hundred bucks near me and I’m in Maine so it’s a pretty dead market. I mean it will work but certainly won’t be as efficient

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Whoa. How does the “tonne” equate to BTUs? I feel like you’ve probably answered that somewhere lol



I’m estimating about 9,000 BTU equals one horsepower of chiller heat removal

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Well I’m certainly intruiged to say the least. Might be a good little venture selling some scavenged condensers with AC units attached and kick the shit out of everyone’s rotavaps :stuck_out_tongue:



Maybe… Combine the freezer + AC unit?! Have a big ol reservoir coupled with cooling power of AC.

Obviously best served with down time at night for it to be useful.

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Yes that’s the direction I’m headn!



Yessir I’m thinkn a big ol freezer mines around 24cf then oh about ten 10,000btu ac units all hooked together inside the sucker for my chiller $4000 beats $30,000 and 3 phase any damn day!

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