The story of this chiller started about a year ago when I purchased a 1/2hp DIY chiller off of eBay for about $350. The chiller worked great until my ReefKeeper when out for the second time and I had to try and manually regulate the temp in my system by turning the chiller on and off during the day. I know know that this is not a good thing to do, the problem is that by allowing the temp to rise and asking the chiller to repeatedly cool down a large temp span created to much pressure in the refrigerant lines for a DIY chiller to handle. The cooling coil finally burst after about 4 days of manually turning it on and off. I started researching how to make a more efficient chiller than what was available to the hobbyist mostly because chillers at and above 1/2 hp become ultra expensive. I started talking with a heating and air guy that helped design and install heating and cooling units in downtown Little Rock by using the Arkansas River as the heat exchanger medium. I was fascinated by some of the work that he had done and he helped me get the parts together for a super efficient chiller. The main piece was a "plate and frame" heat exchanger that was made by WCR Regasketing made of Nickel for marine applications. The surface are for heat exchange is exponentially higher than what you will find on a titanium coil exchanger. The cost of a custom build was only $220 so the final exchanger has 8 plates but is quite heavy at around 8 lbs. One of the helicopter mechanics at work figured out that my old chiller was noting more than a window unit so we purchased a 5000BTU air conditioner from Walmart and took the guts out and replaced them with the Nickel plate and frame heat exchanger. The result was fantastic, a chiller that looks custom and mounts in a window with the original hardware that came with the air conditioner. I have not been more pleased with the outcome of any DIY project that I have ever done. The chiller chilled 5 gallons of water 20 degrees in about 13 minutes - pretty amazing in my book.
Wow Chris, you outdid yourself on this one. This is a really cool idea. Good job. Do you have any more detailed pictures of the construction process?
That's very cleaver. I always thought chillers had to be overpriced while comparing it to air condition units and wondered why. I guess because they can put a large price tag on their units and get it. I think many of us will be interested on DIY instructions. Great job!! Eddie
Chris I am interested in maybe having you make me one of these. I am having problems with my 1/2 horse chiller, and will need another chiller soon as it is warming up outside. I would go with a larger BTU unit probably. Do you have any pics of the heat exchanger?
Here is the link to the people that did the heat exchanger build: http://www.wcr-regasketing.com/bhe-advantages.htm Stan discussed building one for someone if they wanted it when we hooked this one up. The most expensive part is the plate and frame heat exchanger and then you can purchase the size window unit that you want. The representatives at WCR will ask you a lot of questions about flow rate and such that you will need to get for them. They will send you a build to approve and it took them about 6 weeks to get it done. It is definitely not an overnight project but you save about 1/3 the cost of a regular chiller and have a unit that is 10x more efficient and can be vented outside easily.
i need pics of how you tied it all together if you could possibly spare them. any guess on how big of a tank will that handle ?
Sorry I did not take any pictures when we were putting it together, I knew very little about refrigeration so Stan did most of that work. My tank is about 200 gal total volume with refugium but I suspect that it could do another 50 to 75 without any problem but that is just speculation.
Does Stan work for the company that made the heat exchanger? I did not see his name on the contact list at the link you provided. Do you have a number for him?
No - Stan works with me at Angel One. You will just need to contact the company and they will put you intouch with the correct sales person for this geographical area. Stan just knows how to put all of the pieces together. It was a female that I dealt with and the only female listed for them is Mary LeConte so I would start with her.
I saw the heat exchanger before it was installed and its a very nice design. If I needed a chiller this would probably be what I would go with myself.
thats what i was wondering as well. most heat exchangers will have coils inside the main body so i am assuming the freon lines are running thru the center and the tank water is flowing thru the outer areas. what i cant figure out is where it was mounted in the unit unless the original exchanger was completely removed and installed there. but if not then this thing would be serving both dehumidification purposes and water temps while venting outside. help us out chris, inquiring minds want to know.
I was just curious, do you have a wattage comparison of your new unit vs your old one? I am interested to see exactly how much more efficient your unit is. Also, does anyone know what the material inside a aquarium heat exchangers is. I have found that titanium and cupro-nickel are the two most common, but there are likely to be more. I am thinking about starting a little project myself and just need a little info.
Here is a pretty general discription of how an A/C unit works, but this applies to all types of refrigeration. In refrigeration you have a high pressure coil (the coil that the heat comes off of out side) and low pressure coil (coil that your cold air comes from). The compressor compresses the freon which makes it hot then it gets cooled in the high pressure coil. Then there is a flow limiting device that only allows the now not so hot freon to flow out of the high pressure lines into the low pressure coil expanding and cooling down even further (real cold like we like our A/C). The the cycle repeats until the temperature set point is hit. There is also a pressure switch that doesn't allow the compressor to over pressurize the system. So replace the low pressure coil (cold coil) with the chiller heat exchanger.
