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