Super Cooler for an Air Conditioning System

The invention disclosed relates to air conditioning systems and more particularly relates to improvements in the condensing of the refrigerant in an air conditioning system.

A conventional air conditioner, especially smaller units for homes, includes an exterior portion including a forced air cooled compressor and condenser coil unit which is positioned in a self-contained housing outside of the home, and an evaporator and blower unit inside the home. The function of the condenser coil is to remove heat from the compressed refrigerant, which enters in a gas phase, thereby condensing the refrigerant to a liquid phase prior to entry in the evaporator coil. The liquid refrigerant subsequently expands to a cold gas in the evaporator coil, which cools air circulated past it by the blower inside the home.

The air conditioner is more efficient if the refrigerant leaves the condenser coil and enters the evaporator at a cool temperature. Moreover, since various refrigerants normally condense at temperatures within the range of 100.degree.-130.degree. F., a given refrigerant may not completely condense into a liquid in extremely hot weather, especially if the condenser is exposed to the sun and unshaded. Thus it is desirable to keep the condenser coil as cool as possible.

One technique disclosed in the prior art to cool the condenser coil has the lowermost condenser coils immersed in a water bath such that the coils are cooled by simple conduction. Heat transferred by the refrigerant to the water bath is dissipated by evaporation in the form of spraying the bath water in a fountain. Another technique disclosed in the prior art to cool the condenser coil in an automobile air conditioner, has the coil immersed in the water condensate which has been collected from moist ambient air which has passed over the refrigerant evaporator. None of the prior art techniques however can be easily adapted to an existing compressor/condensor housing in a domestic air conditioning system. None of the prior art mechanisms which carry out these techniques lend themselves to easy installation on an existing air conditioning system by the homeowner himself.

It is therefor an object of the invention to provide an improved air conditioning system.

It is another object of the invention to provide a means for more efficiently cooling a forced air cooled condenser coil in an air conditioning system.

It is still another object of the invention to provide a means to make an air conditioning system more efficient, which is easily installed on an existing unit.

It is yet another object of the invention to cool the condenser coils in an air conditioning unit in an improved manner.

It is a further object of the invention to cool the compressor in an air conditioning unit in an improved manner.

These and other objects, features and advantages of the invention are accomplished by the super cooler invention disclosed herein. Water condensed from the air drawn over the refrigeration unit of an air conditioning system is collected and directed into a first chamber of a dual chamber reservoir where it is pumped through heat exchanger coils. The heat exchanger coils are placed upstream of the condensor, thereby lowering the air intake temperature. Furthermore, the heat exchange coils can be in thermally conductive contact with a fibrous heat exchanging air filter placed across the air intake part of the air-cooled refrigerant condensor for the system. The chilled condensate would conductively cool the filter, lowering the air intake temperature. The condensate is then directed to the top of the filter where it is poured onto the filter and allowed to flow down the fibrous surface, thereby evaporating. The latent heat of vaporization in this process further cools the filter which, in turn, further reduces the air intake temperature. Scale deposits fail to form on the filter because the condensate is distilled water. Any condensate not evaporated from the surface of the filter is collected in a trough at the bottom and returned to a second chamber in the dual chamber reservoir where it is mixed with previously cycled water. Excess water in the second chamber will overflow into the first chamber and will be recycled. The reduction in the air intake temperature for the air-cooled condenser results in a more efficient operation for the overall air conditioning system. A second super cooler unit can also be employed to enhance the forced air cooling of the refrigerant compressor. The heat exchanger can be easily installed on the air intake port of an existing air-cooled condenser unit. It is suitable for domestic central type and window type air conditioners and can be installed by the homeowner using simple household tools.

These and other objects, features and advantages of the invention will be more readily appreciated upon reviewing the accompanying figures.

FIG. 1 illustrates the overall system context of the super cooler invention.

FIG. 2 is a detailed illustration of the super cooler invention.

FIG. 3a is a detailed front view of the construction of the heat exchanging air filter.

FIG. 3b is a side view of the filter of FIG. 3a.

FIG. 3c is a top view of the filter of FIG. 3a.

FIG. 4 illustrates an alternate embodiment employing a second super cooler to cool the refrigerant compressor.

The system context for the super cooler invention is shown in FIG. 1 where a conventional air conditioner system is shown which includes a chilling portion 2 including a blower unit 4 for creating an air flow 6 into the unit from the compartment 11 to be cooled, drawing the air over the refrigerant evaporator coil 8 and then back in the direction 10 to the compartment 11. The system further includes the refrigerant compressing unit 22 containing a forced air cooled compressor 64 and condenser coil 24. The function of the condenser coil 24 is to remove heat from the refrigerant compressed by the compressor 64, which enters in a gas phase, thereby condensing the refrigerant into a liquid phase prior to entry in the evaporator coil 8 via the expansion valve 9. The liquid refrigerant subsequently expands to a cold gas in the evaporator coil 8, which cools the air 6 circulated past the evaporator 8 by the blower unit 4.

When the ambient air has a relative humidity of greater than approximately 45%, substantial quantities of water are condensed from the air flow 6 as it passes over the evaporator coil 8 in the refrigerating unit 2. This water condensate drips over the region of the coil 8 and collects in the collector 12, at a temperature of approximately 40.degree. F. The water condensate is conducted from the collector 12 through a thermally insulated pipe 14 to an input of the pump 16.

Mounted on the air intake port 25 of the compressor housing 22 proximate to the condenser coil 24, is the super cooling unit 20 which includes the heat exchanger coil 40 and fibrous heat exchanging filter 48. The pump 16 pumps the chilled condensate through an output pipe 18 to the heat exchanger coil 40 in the super cooling unit 20, at the input A. The chilled condensate flowing through the heat exchanger coil 40 lowers the termperature of the air flow 21 flowing across the condenser coils 24, thereby augmenting the cooling of the condenser coils 24. The chilled condensate in the heat exchanger coil 40 is then conducted to the end 42 as is shown in FIG. 1, where it flows into a trough 44 containing a plurality of holes 46, shown to better advantage in FIG. 3c. Mounted beneath the holes 46 is the fibrous heat exchanging air filter 48 into which the chilled condensate is dripped so as to saturate the filter 48. The air flow 21 produced by the fan 26, passing through the fibrous heat exchanging air filter 48, induces evaporative cooling of the filter which in turn further reduces the air intake temperature for the air flow 21, further augmenting the cooling of the condenser coils 24. The super cooler thus chills the intake air to the condenser unit with a two-stage condensate cooling cycle.

Condensate which flows to the bottom of the filter 48 without evaporation, is collected in the U-shaped trough 54 and is directed from the super cooler 20 through the outlet B and through the pipe 28 to the pump 16.

The pump 16 is shown in FIG. 2 as a dual chambered pump having a first chamber 32 wherein the chilled condensate flowing from the input pipe 14 is pumped by the pump 30 to the super cooler's heat exchange coil 40 over the outlet pipe 18. Water which has circulated through the super cooler 20 and has been collected by the collector 54 is directed through the input pipe 28 to a second chamber 34 where the water is mixed with previously recycled water. The first chamber 32 is separated from the second chamber 34 by a dam 36 over which excess recycled water in the chamber 34 may flow, to be mixed with fresh condensate from the input pipe 14. Excess quantities of recycled water in the chamber 34 are eliminated from the system through the overflow pipe 38.

The super cooler 20 is employed as a subcooler for the condenser 24 on an air conditioner or other refrigeration system to substantially increase its efficiency. The pump 16 dissipates little power, having a motor of approximately 1/60th horsepower. Experimental trials of the super cooler system show that the power required to cool the compartment 11 can be reduced by 10-20%. The system is designed for use in geographical regions having high relative humidity, but can be used in environments having a relative humidity as low as 45%.

Several design modifications can be made with respect to the elements of the invention without departing from the spirit and scope of the invention. For example, the preferred material of which the fibrous heat exchanging filter is composed is hog's hair, plastic or fiberglass. The consideration to be made is first, that the solubility of the material be quite low in the water condensate so as not to cause the accumulation of any sludge in the system. The second consideration is the thermal conductivity of the material. A higher thermal conductivity for the filter 48 is desirable when placed in contact with the heat exchanger coil 40 if heat is desired to be extracted from the heat exchanger filter 48 by the coil 40. The effective surface are of the coil 40 is increased when the filter 48 is in conductive thermal contact with the heat exchanger coil 40. Other possible materials for the filter 48 can include stainless steel or chrome plated copper.

The super cooling assembly 20 is very convenient to install, requiring only two clamps to position it in front of the air intake port 25 of the condensor housing 22. FIG. 3a shows how the filtering material 48 is held in place within the frame formed by the pipes 44, 54, and 58, by means of plastic rods 50 and 52. In this manner, new filtering material can be easily replaced on a periodic basis without disassembly of the apparatus.

The pump 16 can be driven off the motor powering fan 26.

The entire assembly shown in FIG. 3 can be made from drip molded plastic or can be assembled from separate lengths of plastic pipe composed of, for example polyvinylchloride.

FIG. 4 illustrates an alternate embodiment of the invention wherein the condensate pumped by the pump 16 is output over the pipe 18.degree. to two super cooling units 20' and 20, cooling the refrigerant compressor 64 and the condenser coils 24, respectively.

In one embodiment, the pipe 18' can be optionally wrapped about the compressor 64 as the coil 70 to conductively cool the compressor 64. Coil 70 then returns to the pipe 18' which directs the condensate to the input A' of the super cooler 20' of FIG. 4. Super cooler 20' of FIG. 4 is identical to the super cooler 20 shown in FIGS. 1, 2 and 3, with the input A' corresponding to A and the output B' corresponding to the output B. After the water has completely flowed through the super cooler 20' it passes via output B' to the pipe 28' and can optionally return to the pump 16 or, through an auxilliary pump 16', be pumped through pipe 18 to the input A of the super cooler 20. The super cooler 20 shown in FIG. 4 works identically to that shown in FIG. 1. The addition of this pre-cooling system 20' increases the condensate temperature somewhat, estimated to be between 4.degree. and 10.degree. F, and therefore decreases somewhat the efficiency of the super cooler 20 cooling the condenser 24. However, the overall efficiency of the system is increased by the use of the auxiliary super cooler 20' cooling the refrigerant compressor 64.

In another alternate embodiment water from any source would be supplied to the input of pump 16 with that water being used instead of the condensate in the system.

Means to supply city water or well water could be used. It is likely that the efficiency of this embodiment would be reduced since the temperature of the supplied water would be much higher than the chilled condensate.

The reduction of the air intake temperature for the air cooled condenser coils 24 and compressor 64 results in a more efficient operation of the overall air conditioning system. The heat exchanger can be easily installed on the air intake port 25 on an existing air cooled condenser unit. It is suitable for central type and window type air conditioners and can be installed on domestic units by the homeowner using simple household tools. The super cooler chills the intake air to the condenser unit with a two-stage condensate cooling cycle generated by a simplified structure which is easily fabricated, easily installed, and easily maintained.

Although this invention has been described with some specificity, it is understood that the present disclosure is made only by way of example and that many changes in the details of construction and the combination and arrangement of the elements may be made without departing from the spirit and the scope of this invention.