[GpsFrontier]

If you found 18 feet of stainless steel tubing for $7 USD, I am impressed. Even if you still need to bend it, for that price I will buy the tool to bend it (I have a tool, but only for bends, not coils). What I found was around $40 USD and I doubt it was any more than about 8 feet stretched out. I can get 700 feet of 1/2 inch poly tubing for $40 ($39.95+tax).

Just a note on the water temp of the evaporation cooler. I had bought a large portable one to cool my room with, I sold it because it just drove up the humidity in the house, but that was not my point. When I first bought it and brought it home I also got 20 lbs of ice. The cooler held about 5 gallons of water, I dumped all 20 lbs of ice in the water reservoir, then filled the rest with cool tap water. It felt just like an air conditioner (as I imagined it would). That lasted for 20-30 minutes before the ice had all melted and the water was almost at room temp (about 75 degrees F). It cost about $3 USD for the 20 lbs of ice, I quickly found it would be cheaper to run the AC. But that was just my experience. If the water line going in is directly from the the household pipes the temp might be because of the geothermal effects of the underground lines (sounds like the right temp). But you know your system, and how it's set up.

P.S. Pictures would be nice also.