HydroGen Ice Box 8 Inch Water-Cooled Heat Exchanger

Dont waste your money on this product unless you believe in snake oil. Hooked to a 3/4 hp chiller i had no change in temp.

This is OK if you have a cold water source that stays cold. If you don't then, like the other reviewer said, you need a chiller. Its basic thermodynamics. So if you just run it to a small water source, you will heat that water quickly. But the product does what it should - that is move the heat from the hot exhaust to cold water source. The best thing that these could be used for is to transfer the heat to a geothermal heat pump. Or use it to preheat your domestic hot water, etc. I heat a spa that isn't used, then drain and refill with cold water. Keeps your tent cool in the summer, but if you don't have a cold sink, it will only bring the temps on both sides to equilibrium.