Glycol chiller from air conditioner

Maybe Thought I'd document at least how far I get. Here's the unwitting test subject. The faux wood is epic.



A little surgery and we find the evaporator coils and a mess o' 10 gauge wires.



And a capacitor.



Here's the side view.



That's it so far. More later.

-Joe

 

If you could dissolve the aluminum fins from around the evaporator coils, and then soft solder 3/8" copper along as much of the remaining copper tubing you can, and you would have a better chance of keeping the unit working. Moving or bending the existing copper tubing will probably cause a leak and then you have the cost of repair and recharge or the end of the project.
Plan "B" would be to remove evaporator coil while saving the capillary metering tubes, and then use a "ChillZilla" type cfc for the freon to glycol heat exchange.

 

Any progress? Love to see and know what ya did.

I have a small a/c unit I wanta use for a ferm chiller, Looking for ideas.

 

Does giving up count as progress? With the amount of effort it's going to take to rig this into something that may or may not work, I'm probably going to use an aquarium chiller instead.

-Joe

 

LOL , Well at least you started LOL OK , I'll keep looking for ideas, Thanks for letting me know! I was just looking for downfalls and pluses for using an A/C unit.

 

come on, quitters never win!

for mine all i did was bend the evaporator 90 degrees downwards and build a foam box around it. then i filled the box with antifreeze which circulates thru a 1/4" x 20ft copper tube in the kegerator.

gets 40 gallons from 70F to 35F in about 2-3 hours. using a fish tank chiller not only would cost way more than $20, but would take days instead of hours. it can be done if you try.

 

Why would it take days? The chillers are designed for 30+ gallon tanks. I'd be using it to keep a reservoir of coolant cold with a separate pump to run the coolant through the beer. I don't see why that would take longer than an air conditioner keeping the same coolant reservior cold.

Yes you're right, cost is an issue. But so is space and reliability for me.

-Joe

 

'days' might have been a little hyperbole, but the ones i see on ebay for $4-500 are all 700-800 BTU.

for a 35F degree change (70F to 35F) in 40 gallons of water, it requires the removal of 11,620 BTUs.

divide by 700 BTU's an hour = ~17 hours. the compressor will be working 100% for 17 hours strait. almost 6 times longer than an air conditioner, at hundreds of times the price. sure an all-in-one unit might be worth it to some people, but $20 vs $400 was a no brainer for me. space and reliability requirements are different for each situation and user.

fish tank chillers are meant to hold 30 gallons at a set temperature. the only thing they fight against is the influx of heat from the environment. a glycol chiller needs to be able to remove heat from the kegs/carboys that constantly get changed in and out. that is a much higher heat load. they do work, and may even work well (depending on your standards of the word and your setup)- but its not optimal.

 

I certainly can't argue with the math, but I'm a little confused by this bit. The glycol chiller would be removing heat directly from the glycol that is being pumped through a coil in the fermenter.

The glycol reservoir would already be cold before fermentation starts, and the beer will already be down to within a few degrees of where it's supposed to be. So the chiller will only have to remove environmental heat and the heat generated by fermentation, plus it will have all the thermal mass of the already-cold glycol to buffer it.

I'm not sure where the changing out of kegs/carboys comes in.

-Joe