Super Beverage Cooler

To create an instant beverage cooler from an old water cooler.
Replace the compressor with a bigger one, replace the condensor with a bigger one, chop a couple feet out of the middle, charge it with propane & fill the tank with brine!

Step 1 Out with the old

After the sheet metal & plastic sides are removed, this it what is left.

Comments

[headdead]

Got a link to the chart?

[hg341]

nice i would like to make 1

[Pocket Universe]

I'm not sure that I'd dare to keep that baby around the house but it's a damn cool project (no pun intended), that's for sure.

[bikerbob2005]

1.2 oz of propane scares you?my hobby torch uses 12 or 16 oz cans .my pocket torch for radio shack holds about an oz of butane and its clear plastic :O

[Pocket Universe]

What can I say, you're a brave man :-)

[Esmagamus]

I loved your instructable and I'm considering making a mod like this, but there is one piece of information I haven't stumbled upon yet: How do you calculate the necessary amount of propane to charge the circuit with? Do you just use a pressure regulator and leave the tank to fill the system to the pressure set in the regulator or do you make some kind of calculation based on the ideal gas law? Also, what kind of oil can be used with propane? Mineral?

[o4tuna]

Well, I hate to be this way. But, if you don't know, you really shouldn't mess around with refrigeration. The government REALLY frowns on it. If you're really interested, I would suggest contacting your local technical college. They most likely have a 1 quarter class for getting your EPA universal refrigeration card. Not only will you learn the safe & legal methods of handling refrigerants, you will learn about oils, expansion devices & charging.

[Esmagamus]

Well, there is no EPA or US government to worry about here (not in the US). Still, I was wondering how you managed to calculate the amount of refrigerant needed. I've been hunting through the US Army refrigeration course and I can't find that in any part of it.

[o4tuna]

The amp draw of the motor is a given. It will draw more or less, depending upon the charge. You just fill it to around the amount it's supposed to have (should be able to get from device's data sheet/plate), then use an amp meter to fine tune it.

This particular type of cooler uses a very small tube, called a cap tube for metering the refrigerant. The diameter & length were found on the data plate. The temperature/pressure chart said for propane, I should use a different length/diameter. But, I calculated it out, volume wise, and they were very close numbers, so I used the original cap tube(the numbers are in the instructable).

Basic refrigeration:
If you hold up an aerosol can & spray it, the escaping gas is very cold, because it is expanding. If you did that in a sealed system, with a means to heat up the gas, collect it, recompress it & send it back to your spray can, you have a basic refrigeration system.

The liquid refrigerant is squirted through the metering device, into the evaporator, where it becomes a (compressible) gas, by both expansion & being heated (by the heat from what you're trying to cool!), then it goes to the compressor, where it is compressed, then on to the condensor, where it gives off its heat to ambient (the room, usually) & goes back to a liquid. Rinse, repeat...
animated refrigeration cycle
detailed picture

[Esmagamus]

Thank you! It's just the pieces of information I was trying to find, the only issue is that the motor didn't have the data plate on it, so I'll have to try something else. Cool ideas!

[Esmagamus]

Does it have an expansion bulb or waterver you call that little copper bulb?

[o4tuna]

The propane tank is almost the same size as the chopped down cooler.

Propane needs oxygen to combust. There isn't any in a hermetically sealed system.

While most refrigerants are not flamable, they do contain a good deal of oil. A leak would let an atomized mixture of oil escape into the atmosphere. I hear it can make a dandy fire ball. (just do a search on George Goble).

My understanding is that propane usage is fairly common in Europe & Asia. Also in use in stationary & industrial refrigeration in the US.

The purpose of using propane is to lower the critical temperature (and a bit of experimentation). About 1.2 oz of propane was used...

Only two parts of the original water cooler were replaced. The water dispensing apparatus was disabled. The frame, enclosure, tank well, thermostat, metering device & evaporator from the original water cooler were all used. The evaporator & compressor were resized to meet the temp criteria. Fans (& a transformer) were added to help reject the extra heat. The frame & sides were then cut down to the much more manageable size, owing to the more compact size of the replacement condensor.

Yes, I am epa 608 certified. All procedures were conducted appropriately. The unit was non-functional, so I consider this to be recycling/re-using.

I think it will live a long life in its new home...

A good intro to the subject:
http://en.wikipedia.org/wiki/Refrigerant
A list of the multitude of things which can be used as a refrigerant:
http://en.wikipedia.org/wiki/List_of_refrigerants
(Does the EPA know about this R718 stuff? Sounds pretty dangerous!)

references:
http://www.google.com/search?hl=en&q=refrigerant+fireball+atomized&btnG=Google+Search
http://en.wikipedia.org/wiki/George_H._Goble
http://www.autofrost.com/
http://www.duracool.com/

Even frickin' greenpeace likes it:
http://archive.greenpeace.org/ozone/excuse/5excuse.html

[Myself]

Wow, I stand corrected! My assertion of propane's greenhouseness was guilt-by-association with methane, which appears to have been a laughably invalid assumption. My apologies. I'm still curious as to how necessary the new compressor and condenser were. Isn't the target temperature for the can of pop within the original water cooler's range? Or was it the need for speed, and a dramatically-colder bath temperature to quick-chill the can, that drove the upgrades? Given that you're getting below freezing now, will a can explode or deform if left in the bath too long? How loud is the unit when the fans are running? I'd imagine that their speed is easily adjustable, being DC-driven. The near-silence of water coolers has always been an attractive feature. Is the new compressor similarly demure?

[ScottSEA]

Gotta say, I love it when someone is big enough admit it, and then apologize when they make a mistake. Almost as cool as this instructable. Excellent.

[o4tuna]

Well, each refrigerant has a specific temperature/pressure characteristic. Propane runs about 25 degrees cooler than the refrigerant used in watercoolers(with a hair less head pressure). Insulating the tank would allow the compressor to run less, but would not lower the minimum temparature achievable. Lowering the design temp means that you must reject more heat, requiring a larger condensor/forced air removal. The compressor in the original was shot, the bigger one just happened to be handy, but contributes to the lowered brine temp (as was the new condensor, just stuff from the junk pile...). The intial design criteria was a goal of chilling an aluminum can (better heat transfer) of one's favorite beverage to the low 30s F in around 2 minutes. To achieve this, a target brine temp of 12 F was shot for. We achieved 12-18 F. The original temp was around 35-38 F. We left a can of Mountain Dew in for about 40 minutes, it turned into a slurpy. I think the sugar & carbonation act as antifreeze. Alcohol would also have a lower freezing point... The unit is actually quieter than some of the stock coolers, as the compressor is not working as hard. The fans don't make much noise (or I'm immune from being around PCs all the time). We actually were initially thinking about putting a potentiometer in the circut, to trim the speed, but the temps seem to be doing ok without it.

[Myself]

So what you're saying is "build a beverage cooler that looks like a water cooler, but in fact shares almost none of the original components".

It would've been 10x more interesting if you'd found a way to do it *without* junking most of the parts that make a water cooler a water cooler. Say, by adding insulation around the top pot so it'd reach even colder temperatures on the stock cooling unit. Or something.

Anyway, propane's a greenhouse gas so I hope you recover it properly when you reuse these parts for another project. As I'm sure you did for the refrigerant that was already in it, right?

[Mr. Smart Kid]

also propane is not in the atmosphere, IT"S MAN-MADE

[assplosionz]

you are a fool propane is not a greenhouse gas and dont criticise his work if you can do better i would love to see

[lemonie]

Cooling systems used to be filled with nice safe non-flammable chlorofluorocarbons, but since they're almost globally banned we're back to the likes of propane & possibly ammonia(?). As commented, in a closed system there's no problem. Of course before CFCs fridges used to be filled with ammonia etc...

[krusty]

Is there any risk of fire/explosion from using propane as the refrigerant ?

[The Moog]

I wouldn’t recommend using propane, why do you think manufacturers don’t, they only use inert gas.

[trebuchet03]

Only if it leaks - otherwise, not really ;)

[TheCheese9921]

needs spinners thats uber awsome

[trebuchet03]

the perspective makes the propane tank look HUGE!

[bleachworthy]

gimme one!