Experimenting with cooling things with ice

This ice chest is big.  It can freeze things pretty well, so the flash came to me that I can double its value by having it freeze water, or some other liquid, and then run it through a heat exchanger.  After going through the heat exchanger, a small fan will blow air through it and yield.... ta da!!! cold air.

I checked out the necessary hardware and can visualize how to put it together.  But is it worth it?

Looking at the BTU numbers for a 2 liter bottle, it looks rather impressive how much heat can be stored in ice.  Or used to take heat from the air, to be more accurate.

Currently, I'm running an experiment to see how cold the water gets with the ice bottle in it, how long it takes to melt it off and so forth.  There's a new bottle in the freezer to take place of the one in the kitchen sink with 3 gallons of water.  That's about a 6 to 1 ratio of water to ice.  It should lower the water temperature 7 degrees, but it feels like it has already done that much and more.  What could I have done wrong?  The bottle came out a 0 degree Farenheit, so it actually has to travel nearly twice as far.  The water should drop about 14 degrees.

Well, it looks like the sink is losing water.  The water is quite cold, but there's less of it.  The experiment isn't going to yield anything useful.  It will have to be redone.

However, it does show that the water will definitely get cold.  But it might take a little while.


Update:

There's another bottle in there that I kept overnight, but it didn't complete freezing.  So now I'm wondering about the capacity of this freezer to freeze stuff.  If it can't freeze several of these overnight, then it won't be as much use as I thought it might be.