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This is an aquarium chiller that has been modified to cool down to 32 degrees Fahrenheit (0deg C). It features a refrigeration system including a compressor that uses R134A refrigerant and is rated at 240 watts. The heat exchanger inside is made from Titanium to permit the unit to be safely used with salt water aquariums without corroding. That may be a good feature for imaging: I'd not want to have it rusting on me, even though I have no intent to use salt water.
It is good for maintaining the water bath at low temperatures. It does take some time to chill the water down, perhaps 5 degrees per hour, but it has not been accurately measured yet (received the unit on May 4, 2004).
My expected usage pattern will be to prechill the water to get it cold enough that the camera can cool to the desired operating temperature with less than 90% power being initially applied to the camera's built-in peltier cooler. The chiller then will further reduce the temperature of the water as the night wears on, which will permit the peltier cooler in the camera to draw progressively less power.
Although a bit pricey at $360.00, the solution is self-contained and simple to plumb and use. I purchased it here. The vendor was very responsive and shipped the unit out immediately upon receiving my order.