I explain the coolant flow system of my diy water chiller. This water cooler has a bottom fridge section, I put a ten foot copper coil submerged in two gallons of rv antifreeze, and another coil in the top water chiller part (1 gal TV antifreeze) then the freshly chilled coolant goes through the tube, out the end, thru the safety sensor, and back into the reservior.
