I was just looking at the price of a chiller....WOW! I came up with an idea to use a small dorm sized refrigerator. Take a 5 gallon bucket and wrap 1/2 inch clear tubing around it from top to bottom. drill the side of the fridge, put in two 1/2 inch bulkheads to slip the tubing through. Set the bucket in the fridge (I figure fill with antifreeze for extra cooling and antifreeze cause it doesn't go bad), use a pump on a controller so that when the water gets hot the pump circulates water from the sump to the unit and back. I figure if you picked up used stuff you could probably do it for $125-$150. I don't know how efficient it would be but I thought we could all toss the idea around. Granted you would need plenty of room for the unit but it could also hold a six pack. Can your inline chiller do that?
I see several problems (losses) with this setup. The heat transfer between your anti-freeze and the frig is a problem. The plastic bucket acts as an insulator. With this being said, your greatest transfer acts on the small area exposed at the top of the bucket. So with that alone you lose alot of your capacity .[/*:m:2dim70ty] The plastic tubing acts as an insulator resulting in another loss.[/*:m:2dim70ty] The frig is small. I don't exactly know how many btu's a mini frig is rated for, but I can only guess not very much. Combined with your losses above I think this setup will not work or at least not work well enough. I believe that the result will be that you will not have the capacity you need and both the frig and pump will run non stop.[/*:m:2dim70ty] I have built a chiller in the past and have a fairly good knoledge of refrigeration. If you would like to talk I would be happy to help. Thomas Franklin 1-479-207-2454
Jason - you must be good at DIY projects I am more like - find a great deal on ebay I admire DIYers though, always great to have one as a friend !
Well the antifreeze was actually just there to serve as a little bit of a boost. The real cooling would come from the contact of cold air with the tubing coiled around the bucket. I do see your point though. I never thought of the BTU's a small fridge could handle. I have seen people turn small window unit air conditioners into chiller though I'm not sure quite how. Haven't really researched it. I have a 46 gallon tank and really don't have cause for one. I was just thinking about it....no plans to build one. And yes nano... I'm very much a DIY'er....southern ingenuity. Thomas, I appreciate the offer of help. When I set up my 135 (probably next year) I may well be hitting you up for your refrigeration knowledge.
i wouldn't use antifreeze. too toxic . might spill some on the floor and your dog might drink it. I doubt plain water won't freeze with your set up. i agree you need an more efficient heat transfer between the tank water and the coolent. maybe something made out of glass?
if you can get your hands on some copper tubing and use that to wrap the bucket. Another consideration is a thick plastic bag or metal can of some type. This would help a LOT with heat transfer. Agreed, if your tank was always hot and had to be running through the "chiller" the fridge would run all the time. On the other hand, if you didn't have really high intensity lighting and only needed to control occasional heat issues, seems it would work. And just a disclaimer, I don't know if copper pipes will leach copper into your tank, so it might also be a good idea to have some type of carbon after the chiller to ensure there isn't any copper in the cooled water.
Please don't even consider copper tubing as a return to your tank. I think Ralph could be a great source of information for this kind of a DIY project. He has a large one running on his system.
+1 ^ Here is a post about a RS member that used a brass fitting & the copper in the brass leached into his tank & killed all his coral. http://www.reefsanctuary.com/forums/red ... -call.html
