# US 5,701,748 A · Evaporative cooler for air conditioning condensing unit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,701,748 A - Document ID: US5701748A - Status: Granted - Kind: A - Application number: 08/659,575 - Filed: 1996-06-06 - Granted: 1997-12-30 - Earliest claimed: 1996-06-06 - Inventors: Jack LeRoy Phelps; Bernard Maurice Paquette - Web page: https://patentgrep.com/patent/US5701748A ## CPC - F25B 49/027: {Condenser control arrangements} - F24F 5/0007: {cooling apparatus specially adapted for use in air-conditioning (F24F5/0046 takes precedence)} - F28D 5/00: Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, using the cooling effect of natural or forced evaporation - F25B 2339/041: of evaporative condensers - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS - F24F: AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING (removing dirt or fumes from areas where they are produced B08B15/00; vertical ducts for carrying away waste gases from buildings E04F17/02; tops for chimneys or ventilating shafts, terminals for flues F23L17/02) - F28D: HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT (fluid heaters having heat generating means and heat transferring means F24H; furnaces F27; details of heat-exchange apparatus of general) ## Abstract An evaporative cooling system externally mounted around an air cooled condenser to increase the rate of heat transfer. Spray cooling takes place in stages around succeeding portions of the condenser as determined by thermostats which respond to increasing condenser air discharge temperature. ## Claims ### Claim 1 In an outdoor air conditioning condensing unit having a wraparound condenser and a top mounted fan to draw ambient air through the condenser in combination with an externally mounted evaporative cooling system to spray water on the condenser to increase the rate of heat transfer, said evaporative cooling system comprising a tubular manifold encircling the base of the condensing unit coextensive with the wraparound condenser, said manifold having an inlet connected to a source of water pressure, a plurality of vertically extending pipes in fluid communication with said manifold and spaced along the manifold to overlie the condenser for its peripheral extent, each vertical pipe being provided with at least one spray nozzle, said vertical pipes being divided into a number of spray stages with each spray stage comprising at least one vertical pipe, an electrically controlled solenoid valve mounted in fluid control relationship in said manifold at the inlet of each said spray stages, a plurality of thermal switches arranged around the condenser internally of the condensing unit at locations to sense the temperature of the air leaving the condenser at the respective spray stage locations, each thermal switch being set at a different but increasing temperature setting, each thermal switch being electrically connected with a manifold solenoid valve associated with its respective spray stage whereby a modulated spray pattern is generated across said condenser as a function of condenser discharge air temperature. ### Claim 2 (depends on 1) The combination of claim 1 wherein the water pressure inlet is connected to one end of the manifold and the solenoid valves are connected in series flow relationship. ### Claim 3 (depends on 1) The combination of claim 1 wherein the water pressure inlet is connected to the manifold to divide it into two separate branches. ### Claim 4 (depends on 2) The combination of claim 2 wherein each spray stage and its associated inlet solenoid valve counting downstream away from the water pressure inlet are sequentially energized in accordance with an increasing temperature program as determined by the setting of the thermal switches. ### Claim 5 (depends on 3) The combination of claim 3 wherein each spray stage and its associated inlet solenoid valve counting downstream away from the water pressure inlet of each branch are sequentially energized in accordance with an increasing temperature program as determined by the setting of the thermal switches. ### Claim 6 (depends on 1) The combination of is claim 1 wherein a sail switch is mounted within the condensing unit on the opposite side of the condenser from the spray stage operative at the lowest temperature setting to close a circuit to a signalling device when the condenser is partially blocked. ### Claim 7 (depends on 1) The combination of claim 1 including a contactor for supplying power to the compressor when energized, a stepdown transformer having a 24 volt secondary for supplying power to the electrical components of the evaporative cooling system, the primary of the transformer being wired in parallel with the compressor whereby said evaporative cooling system is operative whenever the compressor is energized. ### Claim 8 (depends on 1) The combination of claim 1 including a stepdown transformer having a primary winding connected to a source of AC power and a 24 V secondary connected to a sensing device, said sensing device being operative to sense a physical signal resulting from the operation of the condensing unit, said sensing device, when activated, supplies 24 volts to the load devices in the evaporative cooling system. ### Claim 9 (depends on 1) The combination of claim 1 wherein said thermal switches comprise a snap-acting bimetal disc sealed in a protective housing. ### Claim 10 A method of increasing the efficiency of an outdoor air conditioning condensing unit having a wraparound condenser and a top mounted fan to draw ambient air through the condenser, said method comprising installing a tubular manifold encircling the condensing unit coextensive with the wraparound condenser, connecting said manifold to a source of water pressure, installing a plurality of spaced vertically extending pipes in fluid communication with said manifold along the length thereof, providing each vertically extending pipe with at least one spray nozzle, grouping said vertically extending pipes into a number of spray stages comprising at least one vertical pipe, providing an electrically controlled valve in said manifold at the inlet of each spray stage, providing a plurality of thermal switches arranged around the condenser internally of the condensing unit, each switch being set out at a different operating temperature, connecting said switches in circuit with individual electrically controlled valves whereby a modulated spray pattern is directed toward the condenser depending upon the settings of said switches .