MODULAR ADIABATIC PRE-COOLING CASSETTE WITH METHOD OF RETROFIT FOR HORIZONTAL AIR-COOLED COMMERCIAL REFRIGERATION CONDENSERS

Abstract

According to another aspect, the present disclosure relates to a system for modular adiabatic evaporative pre-cooling of a horizontal air-cooled commercial refrigeration condenser. The system includes an evaporative media with an air permeable construction. The evaporative media has a water absorbable construction. The system also has a water supply port for supplying the volume of water. The system also has a water distributer for distributing the volume of water supplied from the water supply port. The water distributer distributes the volume of water to the evaporative media. The system also includes a water drain port for draining the volume of water distributed to the evaporative media.

Claims

1-20. (canceled)

21. A method for managing the operation of an evaporative pre-cooling system for treating ambient air flowing into a coil of an air-cooled condenser, the method comprising: verifying that an air flow condition through the air cooled condenser exists; verifying a set point condition has been reached, wherein the set point condition includes calculating a potential efficiency gain for current ambient conditions; after the air flow condition has been sensed and the set point condition has been verified, activating the evaporative pre-cooling system to deliver water to the evaporative media such that the ambient air passing through the evaporative media is wetted and cooled.

22. The method of claim 21, wherein the step of calculating a potential efficiency gain includes calculating a potential pre-cooled dry bulb temperature approach to a current wet bulb temperature.

23. The method of claim 21, wherein the set point condition is a function of a calculated consumption of water through evaporation.

24. The method of claim 21, wherein the step of verifying a set point condition includes receiving a signal from an ambient air sensor.

25. The method of claim 21, wherein the step of activating the pre-cooling system includes energizing the pump.

26. The method of claim 21, wherein the step of activating the pre-cooling system includes energizing a normally closed supply water valve to an open position and energizing a normally open drain valve to a closed position.

27. The method of claim 26, wherein the positions of the supply water valve and the drain valve are controlled by a water level sensing switch.

28. The method of claim 21, wherein the step of activating the pre-cooling system includes activating a UV light.

29. The method of claim 21, wherein the step of activating the evaporative pre-cooling system includes verifying a minimum water level is present in a distribution pan of the evaporative pre-cooling system before activating the pump.

30. The method of claim 29, wherein the step of verifying a minimum water level includes receiving a signal from a water level sensing switch.

31. The method of claim 21, wherein the step of verifying an air flow condition includes receiving a signal from an air flow sensing switch.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0016] The invention will be described in detail with reference to the following drawings in which like reference numerals refer to like elements and wherein:

[0017] FIG. 1 is an isometric left side angle front view schematic diagram of apparatus illustrating, external components, connections, and overall housing design according to an embodiment of the present disclosure.

[0018] FIG. 2 is a front cut-away view schematic diagram illustrating elements of control switches,

[0019] H.sub.2O recirculating system, and functional components shown in FIG. 1.

[0020] FIG. 3 is a side view schematic diagram of the apparatus illustrating the modular cassette design and mounting hardware utilizing the horizontal flat surface of the existing horizontal air-cooled condenser shown in FIG. 1.

[0021] FIG. 4 is an enlarged view schematic diagram of strut and threaded rod method of retrofit shown in FIG.1.

[0022] FIG. 5 is an exploded perspective schematic diagram of an example evaporative pre-cooler system according to an embodiment of the present invention.

[0023] FIG. 6 is a schematic diagram of the air flow path through an example evaporative pre-cooler system according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0024] An economical solution for retrofitting an existing commercial horizontal air-cooled multi-fan refrigeration condensers with a modular adiabatic evaporative pre-cooling cassette system creating a hybrid evaporative/air-cooled design thereby significantly increasing the energy efficiency of the refrigeration system while minimizing maintenance and water use. The modular evaporative pre-cooler cassette incorporates an integrated plenum with adjustable bypass air design to channel ambient air through the vertically configured evaporative pre-cooler cassette, adiabatically pre-cool the ambient air as it flows across the evaporative media, mix the pre-cooled ambient air with the ambient bypass air, and then channel the pre-cooled air up and through the horizontal condenser coil slab in both single row and double row condenser fan designs utilizing the existing condenser fans for air movement. The modular evaporative pre-cooler cassette is mounted by suspending the apparatus from the horizontal surface of the existing air-cooled condenser with strut and threaded rods providing flexibility in both the horizontal and vertical direction facilitating a simple quick flexible installation. The apparatus utilizes water level and air flow sensing devices to maximize energy efficiency, significantly increase service life of water recirculating system, and minimize water consumption while controlling microorganism growth with bacterial spectrum LED light eliminating water treatment requirements.

[0025] FIG. 1 shows an exemplary embodiment of the present invention retrofitted to an existing horizontal air cooled condenser 32 incorporating upper metal struts 28 with threaded rods 30 suspending multiple evaporative pre-cooler cassettes 36 from the horizontal top surface 32 of condenser. Air flow created by the existing condenser fan 40 is channeled by the integrated plenum 34 across the evaporative media of the evaporative pre-cooler cassettes 36 adiabatically pre-cooling the ambient air. The pre-cooled ambient air is then pulled up and through the coil of the existing horizontal air-cooled condenser 32 and discharged vertically into the atmosphere by the fan 40.

[0026] FIG. 2 shows an exemplary embodiment of the evaporative pre-cooler module and internal components. At a predetermined ambient temperature as controlled by a programmable logic controller, the evaporative pre-cooler cassettes are energized where the bacterial spectrum UV LED light 18 is energized, and the normally closed H.sub.2O supply solenoid 22 and the normally open drain solenoid 24 are energized where the evaporative pre-cooler sumps 36 and the PVC drain line 38 fill with water through the mechanical float valve 20. When the water level in the sump systems reaches a depth as predetermined by the location of the water level sensing switch 10, a contactor relay closes energizing the air-flow sensing switch 14, as the existing condenser fans cycle on and off, the individual recirculating pumps 12 are energized and de-energized based on air flow through the individual condenser fan chamber. When pump is energized, sump water is pumped up and into the H.sub.2O distribution pan 16 where the water is exposed to the bacterial spectrum LED light 18 disinfecting the sump water prior to being delivered to the top surface of the evaporative media 26. Water drains from the H.sub.2O distribution pan 16 at a specific flow rate as required delivering the exact amount of water flow to sufficiently soak the evaporative media 26 per manufacturer specifications. Non-evaporated H.sub.2O collects in the evaporative pre-cooled module sump and is recirculated until the ambient temperature reaches a predetermined set point where the programmable logic controller will de-energize the system retuning the supply 22 and drain 24 solenoids to normal state draining the sump system and shutting off the supply of water to the mechanical float valves 20. The water is supplied to the evaporative media 26 through the H.sub.2O Distribution Pan 16, for example via a plurality of apertures arranged in a pattern to evenly distribute the water across the thickness of the evaporative media.

[0027] FIG. 3 shows an exemplary embodiment for method of retrofit of an evaporative pre-cooler cassette to an existing horizontal air-cooled condenser. The evaporative pre-cooler cassette consists of the evaporative pre-cooler module 36 and associated components as previously described adding the integrated plenum 34 where ambient air is pulled through the evaporative pre-cooler media where it is adiabatically cooled with the pre-cooled ambient air subsequently pulled through the condenser coil slab by air-flow generated by the existing condenser fans. The method of retrofit includes an upper metal strut 28 to support the evaporative pre-cooler cassette, a lower metal strut 36, threaded rods, nuts 30, and lock washers facilitate an adjustable method of retrofit in both the vertical and horizontal directions to accommodate leveling the evaporative pre-cooled cassettes with other evaporative pre-cooler cassettes as required and to accommodate field installed piping for electrical connections while supporting the rear of the evaporative pre-cooler cassette with body of the existing air-cooled condenser 32 sandwiched between the upper 28 and lower 36 metal struts by tightening and securing nuts on the threaded rod.

[0028] FIG. 4 shows an enlarged view of the threaded rod 30 and upper 28 and lower 36 strut assemblies on the module end of the evaporative pre-cooler module illustrating the adjustable nature of the method of retrofit.

[0029] FIG. 5 illustrates an example of the above described elements in an exploded schematic diagram to show the individual parts. The example shows two parts of a plenum, the lower part 100 and the upper part 102. The example includes a mechanical sump fill valve 104, similar to the H.sub.2O supply solenoid above. The example evaporative cooling media 112 is supported within a housing frame assembly 106. The example, includes an H.sub.2O pump 108, similar to the sump system drain solenoid above. The system includes an H.sub.2O level sensing switch 110 similar to the H.sub.2O sensing switch above. A two-layer pre-filter screen 114 can be included to protect the evaporative cooling media 112 secured within the housing 106. The housing or frame assembly 106 supports the evaporative media 112, the screen 114, the sump fill valve 104, the H.sub.2O pump 108 and the H.sub.2O level sensing switch 110.

[0030] FIG. 6 illustrates the direction of air flow through the system described above. Outside ambient air A is pulled through the evaporative media in the housing 106. The air B that passes through the evaporative media is directed by the upper plenum 102 into the lower plenum 100. The lower plenum 100 directs the air B up into the coils in the condenser 32. After passing through the coils in the condenser 32, the air C exits out into the atmosphere through the fan C. The fan C operates to pull the air through the entire process from its position at point A to point B, and to point C.

[0031] An example of the evaporative media 26, 112 discussed above, can be constructed of cellulose, for example a plurality of corrugated cellulose paper sheets with different flute angles, with one steep angle (30-60 degrees, preferably about 45 degrees), and one flat angle (10-20 degrees, preferably about 15 degrees) relative to the general planar axis of the assembly. The corrugated geometry allows for air flow therethrough. The evaporative material 26, 112 is water absorbable. An example of the evaporative material 26, 112 can have a thickness of between about 2-12 inches and preferably between about 4-8 inches. An example commercial embodiment of the evaporative material 26, 112 is CELdek®, specifically model 7060-15.

[0032] The embodiments described above can be manipulated by a control system with intelligent precooling control logic based on potential efficiency gain. This potential efficiency gain operates based on a consistent monitoring of the temperature and humidity in the ambient air. The temperature and humidity are compared with each other to determine the highest potential efficiency, and thus determine whether the above described systems operate or turn off. For example, if the ambient air is very humid, it may be less necessary to operate the above described system even if the temperature is very high. By contrast, if the temperature is very high but the humidity is low, it will be necessary for the above described systems to operate. The control system can also include a low ambient temperature cutoff, such that the system will not operate when it is cooler. There may also be a programmable H.sub.2O system purge control based on site water quality to ensure that the cleanest water is being used in the system.

PARTS NUMBERS

[0033] 10 H.sub.2O Sensing Switch [0034] 12 Recirculating Pump [0035] 14 Air Flow Sensing Switch [0036] 16 H.sub.2O Distribution Pan [0037] 18 UV LED Bacterial Spectrum [0038] 20 Mechanical Float Valve [0039] 22 H.sub.2O Supply Solenoid [0040] 24 Sump System Drain Solenoid [0041] 26 Evaporative Media [0042] 28 Upper Strut Support [0043] 30 Threaded Rod [0044] 32 Existing Condenser Housing [0045] 34 Air Plenum [0046] 36 Lower Strut Support [0047] 38 Connecting PVC Piping [0048] 40 Fan [0049] 100 Plenum Lower [0050] 102 Plenum Upper [0051] 104 Mechanical Sump Fill Valve [0052] 106 Housing Frame Assembly