CI-2658 — Operating Performance of a Water Spray on an Air-Type Condensing Unit

A commercially available condenser sprayer was tested on a nominal three-ton air conditioning unit to determine its effect upon performance and other operating parameters. The sprayer system controls and directs a fine mist of water onto the condenser surfaces, thereby enhancing the heat rejection rate, and improving overall system performance. Because the evaporation rate of the water is influenced by ambient air conditions, the unit was tested over a range of dry bulb and relative humidity conditions of the air entering the condenser.

The experimental air conditioner consisted of the outdoor condensing unit of a split system, modified to operate as a chiller. To facilitate the evaluation of performance, a water refrigerant evaporator was substituted for the indoor air handling unit. Cooling effect was determined by measurement of temperature drop and flow rate of water through the evaporator. In addition to cooling Capacity, other parameters were measured and recorded, including compressor back pressure, compressor current, total current, refrigerant temperatures entering and leaving the evaporator, and total condensing unit power consumption.