I managed to acquire a small refrigerator for use with my cooling project. The goal is to use the evaporator of the fridge to keep my water supply cool. For a really cool way to use this kind of fridge, check out Project Kool.
The white 'U' shaped thing, aka ice tray, in the upper right hand side of the fridge is the evaporator which is where the cooling takes place. The super cold gas flows through the entire ice tray structure.
This design was my first attempt at using the evaporator to cool my water supply. Due to the fairly small contact area between the evaporator and the copper pipes, this little trick didn't work very well. I measured a 0.05F decrease in temperature per 10 second interval with no load. With load, but without using the evaporator loop, the system increased it's temperature by 0.10F per 10 second interval. I never even bothered running the evaporator under these conditions!
Solutions? Well, I have two ideas. Plan A will be to remove the fancy copper pipe. Instead of trying to cool tubing I'll just find a container that can completely submerge the evaporator. This direct evaporator to water supply connection will probably work best.
Plan B will be to use the copper tubes as shown but build up a solid block of ice around them. According to info I've found on the net, and please correct me if I'm wrong, ice conducts heat better than water. This will give me great surface contact with the evaporator but will force me to run my "water" supply well below freezing.
Oh, yeah... Before you jump on me for running the flow in the wrong direction I already fixed that!