Climate-Control System With Sensible and Latent Cooling

FIELD

[0001]The present disclosure relates to a climate-control system with sensible cooling and latent cooling.

BACKGROUND

[0002]This section provides background information related to the present disclosure and is not necessarily prior art.

[0003]Conventional vapor-compression systems are often used to cool a space and reduce humidity within the space. While such systems have generally been effective means to cool a space and reduce humidity, there is a need for a system that provides more efficient and more customized sensible and latent cooling over a wider range of outdoor weather conditions. The present disclosure provides such a system for providing more customized and efficient sensible and latent cooling in the space.

SUMMARY

[0004]This section provides a general summary of the disclosure and is not a comprehensive disclosure of its full scope or all its features.

[0005]In one form, the present disclosure provides a climate-control system including a vapor-compression circuit and an air handler assembly. The vapor-compression circuit may include a compressor, an outdoor heat exchanger, an expansion device, and an indoor heat exchanger. The compressor is configured to circulate a working fluid through the vapor-compression circuit. The outdoor heat exchanger is in fluid communication with the compressor. The expansion device is in fluid communication with the outdoor heat exchanger. The indoor heat exchanger includes a conduit that is in fluid communication with the expansion device. The air handler assembly is configured to force air across the conduit of the indoor heat exchanger. The air handler assembly may include an airflow device having a valve and an air-to-air heat exchanger. The air-to-air heat exchanger may include a first heat-exchanger duct and a second heat-exchanger duct. Air flowing through the first heat-exchanger duct may be in a heat-transfer relationship with air flowing through the second heat-exchanger duct. The airflow device may define a first airflow path and a second airflow path. The first airflow path may include the first heat-exchanger duct. The second airflow path may bypass the first heat-exchanger duct.

[0006]In some configurations of the climate-control system of the above paragraph, the valve is movable between a first position and a second position. In the first position, the valve may allow air to flow through the first airflow path and may prevent air from flowing through the second airflow path. In the second position, the valve may allow air to flow through the second airflow path and may prevent air from flowing through the first airflow path.

[0007]In some configurations of the climate-control system of either or both of the above paragraphs, the valve is movable to a third position in which the valve allows a first portion of air entering the airflow device to flow through the first airflow path and allows a second portion of air entering the airflow device to flow through the second airflow path.

[0008]In some configurations of the climate-control system of any one or more of the above paragraphs, a control module controls movement of the valve based on humidity data received from a humidistat.

[0009]In some configurations of the climate-control system of any one or more of the above paragraphs, the humidistat measures humidity of the air upstream of the airflow device.

[0010]In some configurations of the climate-control system of any one or more of the above paragraphs, the control module compares a measured humidity value from the humidistat to a predetermined limit.

[0011]In some configurations of the climate-control system of any one or more of the above paragraphs, the control module compares a measured humidity value from the humidistat to a humidity setpoint.

[0012]In some configurations of the climate-control system of any one or more of the above paragraphs, the predetermined limit is higher than the humidity setpoint.

[0013]In some configurations of the climate-control system of any one or more of the above paragraphs, the first and second airflow paths are fluidly connected to an evaporator duct that provides air from the airflow device to the indoor heat exchanger.

[0014]In some configurations of the climate-control system of any one or more of the above paragraphs, the evaporator duct provides air to the second heat-exchanger duct downstream of the indoor heat exchanger.

[0015]In some configurations of the climate-control system of any one or more of the above paragraphs, the airflow device includes a housing in which the valve is disposed.

[0016]In some configurations of the climate-control system of any one or more of the above paragraphs, the first and second airflow paths diverge from each other downstream of a first air inlet of the housing and converge with each other downstream of the first heat-exchanger duct and upstream of a first air outlet of the housing.

[0017]In some configurations of the climate-control system of any one or more of the above paragraphs, the air-to-air heat exchanger is disposed within the housing.

[0018]In some configurations of the climate-control system of any one or more of the above paragraphs, the first air inlet of the housing is coupled with a return-air duct and receives air from the return-air duct.

[0019]In some configurations of the climate-control system of any one or more of the above paragraphs, the second heat-exchanger duct defines a second air inlet of the airflow device and a second air outlet of the airflow device.

[0020]In some configurations of the climate-control system of any one or more of the above paragraphs, the second air outlet is coupled with a supply-air duct and provides air to the supply-air duct.

[0021]In some configurations of the climate-control system of any one or more of the above paragraphs, the second heat-exchanger duct defines a third airflow path through the airflow device.

[0022]In another form, the present disclosure provides an air handler assembly for a climate-control system. The air handler assembly may include a return-air duct, a housing, a valve, an air-to-air heat exchanger, an evaporator duct, an evaporator, and a supply-air duct. The housing may include a first air inlet, a first air outlet, a first airflow path, and a second airflow path. The first air inlet may be coupled with the return-air duct and receives air from the return-air duct. The valve may be disposed within the housing and may be movable between a first position allowing airflow through the first airflow path and preventing airflow through the second airflow path and a second position allowing airflow through the second airflow path and preventing airflow through the first airflow path. The air-to-air heat exchanger may be disposed within the housing and may include a first heat-exchanger duct and a second heat-exchanger duct. Air flowing through the first heat-exchanger duct may be in a heat-transfer relationship with air flowing through the second heat-exchanger duct. Air flows through the first heat-exchanger duct when the valve is not in the second position. Air flows through the second heat-exchanger duct when the valve is in the first position and when the valve is in the second position. The evaporator duct may be coupled with the first air outlet and the second heat-exchanger duct. The evaporator duct may receive air from the first air outlet and may provide air to the second heat-exchanger duct. The evaporator may be disposed within the evaporator duct and may include a conduit that is configured to receive working fluid from a vapor-compression system. The supply-air duct may be coupled with the second heat-exchanger duct and may receive air from the second heat-exchanger duct.

[0023]In some configurations of the air handler assembly of the above paragraph, the valve is movable to a third position in which the valve allows a first portion of air entering the housing to flow through the first airflow path and allows a second portion of air entering the housing to flow through the second airflow path.

[0024]In some configurations of the air handler assembly of either or both of the above paragraphs, a control module controls movement of the valve based on humidity data received from a humidistat.

[0025]In some configurations of the air handler assembly of any one or more of the above paragraphs, the humidistat measures humidity of the air upstream of the housing.

[0026]In some configurations of the air handler assembly of any one or more of the above paragraphs, the control module compares a measured humidity value from the humidistat to a predetermined limit.

[0027]In some configurations of the air handler assembly of any one or more of the above paragraphs, the control module compares a measured humidity value from the humidistat to a humidity setpoint.

[0028]In some configurations of the air handler assembly of any one or more of the above paragraphs, the predetermined limit is higher than the humidity setpoint.

[0029]In some configurations of the air handler assembly of any one or more of the above paragraphs, the second heat-exchanger duct defines a third airflow path through the housing.

[0030]Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

DRAWINGS

[0031]The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations and are not intended to limit the scope of the present disclosure.

[0032]FIG. 1 is a schematic representation of a climate-control system 10 having an air low device according to the principles of the present disclosure;

[0033]FIG. 2 is a perspective view of the airflow device;

[0034]FIG. 3 is a perspective view of a heat exchanger of the airflow device;

[0035]FIG. 4 is a schematic representation of the heat exchanger;

[0036]FIG. 5 is a cross-sectional view of the airflow device with a valve in a first position;

[0037]FIG. 6 is a cross-sectional view of the airflow device with the valve in a second position;

[0038]FIG. 7 is a cross-sectional view of the airflow device with the valve in a third position; and

[0039]FIG. 8 is a flowchart illustrating a method of controlling the valve.

[0040]Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION

[0041]Example embodiments will now be described more fully with reference to the accompanying drawings.

[0042]Example embodiments are provided so that this disclosure will be thorough and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

[0043]The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.

[0044]When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected, or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

[0045]Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer, or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer, or section discussed below could be termed a second element, component, region, layer, or section without departing from the teachings of the example embodiments.

[0046]Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0047]With reference to FIGS. 1-8, a climate-control system 10 is provided. As will be described in more detail below, the system 10 is operable to provide sensible cooling and latent cooling (dehumidification) simultaneously and independently of each other. As shown in FIG. 1, the system 10 includes a vapor-compression circuit 12 and an air handler assembly 14. The air handler assembly 14 may be installed inside of a building or home, for example. The air handler assembly 14 may provide air cooled and/or dehumidified to a room or space within the building or home.

[0048]As shown in FIG. 1, the vapor-compression circuit 12 may include a compressor 18 and an outdoor heat exchanger (e.g., a condenser) 20, an expansion device 22 (e.g., an expansion valve or capillary tube), and an indoor heat exchanger (e.g., an evaporator) 26.

[0049]The compressor 18 may pump working fluid (e.g., a refrigerant) through the vapor-compression circuit 12. The compressor 18 could be a scroll compressor (including first and second scrolls with intermeshing spiral wraps), for example, or any other type of compressor such as reciprocating (including a piston reciprocatingly received in a cylinder) or rotary vane compressor (including a rotor rotating within a cylinder), for example. The compressor 18 could be a variable-capacity compressor operable in full capacity mode and a reduced capacity mode. In some configurations, the compressor 18 could include additional or alternative capacity modulation capabilities (e.g., variable-speed motor, vapor injection, blocked suction, etc.). The compressor 18 may include a suction inlet 30 and a discharge outlet 32. The inlet 30 may receive working fluid from the indoor heat exchanger 26. The working fluid received through the inlet 30 may be compressed (by a compression mechanism) in the compressor 18 and may be discharged through the outlet 32.

[0050]The outdoor heat exchanger 20 may include a coil or conduit 21 that receives working fluid discharged from the outlet 32 of the compressor 18. A fan (not shown) may force air (e.g., outdoor ambient air) across the coil of the outdoor heat exchanger 20 to facilitate heat transfer between the outdoor ambient air and working fluid flowing through the coil of the outdoor heat exchanger 20. The outdoor heat exchanger 20 and the compressor 18 may be disposed outdoors (i.e., outside of a building, home, or other space to be cooled by the system 10). The indoor heat exchanger 26 and expansion device 22 may be disposed indoors (i.e., inside of the building, home, or other space to be cooled by the system 10).

[0051]From the outdoor heat exchanger 20, the working fluid flows through the expansion device 22 and then through the indoor heat exchanger 26. The indoor heat exchanger 26 may include a coil or conduit 27 that receives working fluid from the expansion device 22. The indoor heat exchanger 26 may be disposed within the air handler assembly 14 such that air flowing through the air handler assembly 14 may flow across or through the indoor heat exchanger 26. A fan 37 (disposed within the air handler assembly 14 or otherwise positioned to force air to flow throughout the air handler assembly 14) may force air across the indoor heat exchanger 26 to facilitate heat transfer between air in the air handler assembly 14 and working fluid in the indoor heat exchanger 26.

[0052]In some configurations, the vapor-compression circuit 12 may include one or more reversing valves operable to switch operation of the vapor-compression circuit 12 between a cooling mode and a heating mode.

[0053]The air handler assembly 14 may include a return-air duct 38, an airflow device 40 (shown in FIGS. 1, 2, and 5-7), an evaporator duct 42, and a supply-air duct 44. As described above, the air handler assembly 14 may include a fan that may be disposed in the return-air duct 38, the airflow device 40, the evaporator duct 42, or the supply-air duct 44, for example. An air filter may also be disposed in any of the return-air duct 38, the airflow device 40, the evaporator duct 42, or the supply-air duct 44, for example.

[0054]The return-air duct 38 may receive air from one or more rooms or spaces of the building or home and may provide air to the airflow device 40. The airflow device 40 may be fluidly coupled with the return-air duct 38, the evaporator duct 42, and the supply-air duct 44.

[0055]The airflow device 40 may include a housing 50, a valve 52, and a heat exchanger 54. The airflow device 40 may define a first airflow path 56, a second airflow path 58, a first air inlet 60, a first air outlet 62, a second air inlet 64, and a second air outlet 66. In the example shown in the figures, the housing 50 defines the second airflow path 58, the first air inlet 60, and the first air outlet 62. In the example shown in the figures, the heat exchanger 54 defines the second air inlet 64 and the second air outlet 66. The housing 50 and the heat exchanger 54 cooperate to define the first airflow path 56.

[0056]FIG. 1 shows the fan 37 disposed in the evaporator duct 42, downstream of the first air outlet 62, and upstream of the evaporator 26. It will be appreciated, however, that the fan 37 could be positioned in any suitable location in the air handler assembly 14 to force air through the assembly 14.

[0057]The return-air duct 38 may be coupled with the first and second airflow paths 56, 58 such that air in the return-air duct 38 may flow into the first airflow path 56 and/or into the second airflow path 58. Air within the first airflow path 56 is fluidly isolated from air within the second airflow path 58. That is, the first and second airflow paths 56, 58 diverge from each other within the housing 50 (e.g., downstream of the first air inlet 60, at or near the valve 52) and converge with each other at or near the first air outlet 62. Air flowing through the first airflow path 56 flows through the heat exchanger 54. Air flowing through the second airflow path 58 bypasses the heat exchanger 54.

[0058]The valve 52 may be movable among a first position (FIG. 5) in which air from the return-air duct 38 is allowed to flow through the first airflow path 56 and is prevented from flowing through the second airflow path 58, a second position (FIG. 6) in which air from the return-air duct 38 is allowed to flow through the second airflow path 58 and is prevented from flowing through the first airflow path 56, and a third position (FIG. 7) in which a portion of air from the return-air duct 38 is allowed to flow through the first airflow path 56 and another portion of air from the return-air duct 38 is allowed to flow through the second airflow path 58. It will be appreciated that the valve 52 could be movable to additional positions between the first and second positions to adjust the amount of air that is allowed to flow through the first airflow path 56 and the amount that is allowed to flow through the second airflow path 58. In some configurations, the valve 52 may be movable to an infinite number of positions between the first and second positions.

[0059]In the particular example shown in FIGS. 5-7, the valve 52 is a plate or damper flap that is rotatably mounted to a wall 57 that separates the first and second airflow paths 56, 58 in the housing 50. A motor (not shown) may drive the valve 52 among the first, second, and third positions. A control module may control operation of the valve 52 based (at least in part) on a relative humidity of air in the return-air duct 38 or air in the space or room to be cooled. The relative humidity may be measured by a humidistat 70 (FIG. 1) that may be mounted to the return-air duct 38 or mounted in the space or room to be cooled. The control module may also control operation of the compressor 18 based (at least in part) on a temperature measurement from a thermostat and/or a humidity measurement from the humidistat 70.

[0060]The heat exchanger 54 may be mounted to (or within) the housing 50. The heat exchanger 54 may be an air-to-air heat exchanger and may include one or more first heat-exchanger ducts 72 and one or more second heat-exchanger ducts 74 (see FIGS. 1 and 4). Air flowing through the first heat-exchanger ducts 72 is in a heat-transfer relationship with air flowing through the second heat-exchanger ducts 74. The second heat-exchanger ducts 74 define a third airflow path (in addition to the first and second airflow paths 56, 58) through the airflow device 40.

[0061]The first and second heat-exchanger ducts 72, 74 may each include a plurality of layers of airflow paths separated by thin walls. In this manner, the heat is exchanged between air in the first heat-exchanger ducts 72 and air in the second heat-exchanger ducts 74 while preventing mixing of the air in the first heat-exchanger ducts 72 with air in the second heat-exchanger ducts 74. It will be appreciated that the heat exchanger 54 could be configured in other ways.

[0062]The first heat-exchanger ducts 72 may be a part of the first airflow path 56. That is, air that flows into the first airflow path 56 from the first air inlet 60 will flow through the first heat-exchanger ducts 72 before exiting the housing 50 through the first air outlet 62.

[0063]The second heat-exchanger ducts 74 may be coupled to the evaporator duct 42 and the supply-air duct 44. That is, the second heat-exchanger ducts 74 may define the second air inlet 64 and the second air outlet 66. As shown in FIG. 1, the second air inlet 64 is coupled with and receives air from the evaporator duct 42. The second air outlet 66 is coupled with and provides air to the supply-air duct 44.

[0064]As shown in FIG. 1, a first end of the evaporator duct 42 may be coupled to the first air outlet 62 and a second end of the evaporator duct 42 may be coupled to the second air inlet 64. That is, the evaporator duct 42 receives air from the first heat-exchanger ducts 72 of the heat exchanger 54 and provides air to the second heat-exchanger ducts 74 of the heat exchanger 54. The evaporator 26 may be disposed within the evaporator duct 42, or alternatively, the evaporator duct 42 may extend through the evaporator 26. In either case, air flowing through the evaporator duct 42 is in a heat-transfer relationship with working fluid flowing though the conduit 27 of the evaporator 26 (e.g., air in the evaporator duct 42 is cooled by the working fluid in the conduit 27 as the air flows over and/or around exterior surfaces of the conduit 27).

[0065]As shown in FIG. 1, the supply-air duct 44 may be coupled with the second air outlet 66 such that the supply-air duct 44 receives air from the second heat-exchanger ducts 74. The supply-air duct 44 may provide air to the space or room to be cooled.

[0066]With continued reference to the figures, operation of the system 10 will be described. As described above, the control module may (in response to a measured temperature and/or humidity in the space or room being higher than setpoint(s)) operate the compressor 18 to circulate working fluid throughout the vapor-compression circuit 12 and operate the fan 37 to force air through the air handler assembly 14.

[0067]When the fan 37 is operating, indoor air (e.g., from the space or room) is drawn into the return-air duct 38 and flows into the first air inlet 60 of the housing 50 of the airflow device 40. When the valve 52 is in the first position (FIG. 5), all of the air from the first air inlet 60 will flow into the first airflow path 56 (i.e., through the first heat-exchanger ducts 72) and out of the housing 50 through the first air outlet 62. From the first air outlet 62, the air flows through the evaporator duct 42 and through the evaporator 26, where heat from the air is absorbed by working fluid flowing through the conduit 27 of the evaporator 26. Thereafter, the air flows into the second air inlet 64 and into the second heat-exchanger ducts 74. Air flowing through the second heat-exchanger ducts 74 absorbs heat from the air flowing through the first heat-exchanger ducts 72. Air in the second heat-exchanger ducts 74 exits the airflow device 40 through the second air outlet 66 and flows into the supply-air duct 44. As described above, air in the supply-air duct 44 flows into the space or room, thereby cooling the space or room and/or reducing the humidity in the space or room.

[0068]As described above, when the valve 52 is in the second position (FIG. 6) air is prevented from flowing through the first airflow path 56 (and therefore, is prevented from flowing through the first heat-exchanger ducts 72) and all of the air from the first air inlet 60 flows into the second airflow path 58 and bypasses the first heat-exchanger ducts 72. When the valve is in the third position (FIG. 7) or any other position between the first and second positions, a portion of the air from the first air inlet 60 flows through the first airflow path 56 (and through the first heat-exchanger ducts 72) and another portion of the air from the first air inlet 60 flows through the second airflow path 58 (and bypasses the first heat-exchanger ducts 72).

[0069]The control module may adjust the position of the valve 52 (i.e., between the first and second positions and any position therebetween) to reduce humidity in the space or room in a manner that reduces over cooling the space or room. That is, if the control module determines that more humidity reduction is desired, the control module may control the valve 52 to allow more air into the first airflow path 56 (and into the first heat-exchanger ducts 72). Allowing more of the air to flow through the first heat-exchanger ducts 72 (where the air is pre-cooled by the air flowing through the second heat-exchanger ducts 74) will remove more humidity (absolute humidity) from the air that flows into the supply-air duct 44 (i.e., relative to the amount of humidity removed by a conventional air handler that does not have the airflow device 40).

[0070]If the control module determines that less humidity reduction (or no humidity reduction) is desired, the control module may control the valve 52 to allow less air (or no air into the first airflow path 56 (and into the first heat-exchanger ducts 72) and instead allow air to bypass the first heat-exchanger ducts 72.

[0071]The more air that is pre-cooled in the first heat-exchanger ducts 72 will result in more humidity reduction but will somewhat decrease the amount of sensible cooling (i.e., air in the second heat-exchanger ducts 74 is warmed as it pre-cools the air in the first heat-exchanger ducts 72). That is, moving the valve 52 closer to the first position will result in more humidity reduction (more latent cooling) but less sensible cooling of the air provided to the supply-air duct 44. Conversely, moving the valve 52 closer to the second position will result in less humidity reduction (less latent cooling) but more sensible cooling of the air provided to the supply-air duct 44. Therefore, if conditions are such that the temperature in the space or room is at or below the desired temperature setpoint but humidity is above a desired humidity setpoint, the system 10 can operate (with the valve 52 at or near the first position) to reduce humidity without substantially over-cooling the space or room (i.e., the amount of sensible over-cooling is reduced or minimized).

[0072]FIG. 8 depicts a control method that the control module may execute to control the position of the valve 52. At step 100, the control module determines whether the system 10 is operating (i.e., whether the compressor 18 is operating). If the control module determines that the system 10 is not operating, then the control module determines, at step 110, whether a relative humidity of the air in the return-air duct 38 (or in the space or room) measured by the humidistat 70 is above a predetermined limit. The predetermined limit may be higher than a humidity setpoint and could be a value at which humidity would be uncomfortable for most people or a value at which potential for mold growth is high, for example. If the control module determines that the relative humidity is above the predetermined limit (and/or if the control module determines that the temperature in the space or room measured by the thermostat is above a temperature setpoint), then the control module may start operation of the system 10 (i.e., start the compressor 18).

[0073]If the control module determines at step 100 that the system 10 is operating, then the control module may, at step 130, calculate error values of: (a) relative humidity versus a humidity setpoint, and (b) dewpoint temperature versus the setpoint temperature. At step 140, the control module may use proportional-integral-derivative (PID) control to continuously or intermittently adjust the position of the valve 52 to achieve the desired latent and sensible cooling.

[0074]The airflow device 40 and system 10 of the present disclosure have significant benefits over the prior-art air conditioning systems. For example, the system 10 with the airflow device 40 allows for more effective and efficient sensible and latent cooling in a manner that reduces over-cooling. Furthermore, the airflow device 40 is a modular device that can be easily installed into a pre-existing air handling system with relatively simple modifications to the pre-existing system.

[0075]The airflow device 40 and system 10 can provide more customized and efficient sensible and latent cooling in the space or room by selectively exchanging heat between the return air and the supply air of the system 10 (i.e., in the heat exchanger 54 of the airflow device 40). For example, by adjusting the position of the valve 52 (as described above), the portion of cooling dedicated to dehumidification can be modulated to increase the relative humidity of the air upstream of the evaporator 26 by precooling that air with supply air. This causes the cooling within the evaporator 26 to act primarily on air that is saturated with water vapor. In this manner, the system 10 can dehumidify the space or room without over-cooling the space or room, which improves comfort and saves energy.

[0076]In this application, including the definitions below, the term “control module” or the term “controller” may be replaced with the term “circuit.” The term “module,” “control module,” “control circuitry,” or “control system” may refer to, be part of, or include: an Application Specific Integrated Circuit (ASIC); a digital, analog, or mixed analog/digital discrete circuit; a digital, analog, or mixed analog/digital integrated circuit; a combinational logic c circuit; a field programmable gate array (FPGA); a processor circuit (shared, dedicated, or group) that executes code; a memory circuit (shared, dedicated, or group) that stores code executed by the processor circuit; other suitable hardware components that provide the described functionality; or a combination of some or all of the above, such as in a system-on-chip.

[0077]The module may include one or more interface circuits. In some examples, the interface circuits may include wired or wireless interfaces that are connected to a local area network (LAN), the Internet, a wide area network (WAN), or combinations thereof. The functionality of any given module of the present disclosure may be distributed among multiple modules that are connected via interface circuits. For example, multiple modules may allow load balancing. In a further example, a server (also known as remote, or cloud) module may accomplish some functionality on behalf of a client module.

[0078]The term code, as used above, may include software, firmware, and/or microcode, and may refer to programs, routines, functions, classes, data structures, and/or objects. The term shared processor circuit encompasses a single processor circuit that executes some or all code from multiple modules. The term group processor circuit encompasses a processor circuit that, in combination with additional processor circuits, executes some or all code from one or more modules. References to multiple processor circuits encompass multiple processor circuits on discrete dies, multiple processor circuits on a single die, multiple cores of a single processor circuit, multiple threads of a single processor circuit, or a combination of the above. The term shared memory circuit encompasses a single memory circuit that stores some or all code from multiple modules. The term group memory circuit encompasses a memory circuit that, in combination with additional memories, stores some or all code from one or more modules.

[0079]The term memory circuit is a subset of the term computer-readable medium. The term computer-readable medium, as used herein, does not encompass transitory electrical or electromagnetic signals propagating through a medium (such as on a carrier wave); the term computer-readable medium may therefore be considered tangible and non-transitory. Non-limiting examples of a non-transitory, tangible computer-readable medium are nonvolatile memory circuits (such as a flash memory circuit, an erasable programmable read-only memory circuit, or a mask read-only memory circuit), volatile memory circuits (such as a static random access memory circuit or a dynamic random access memory circuit), magnetic storage media (such as an analog or digital magnetic tape or a hard disk drive), and optical storage media (such as a CD, a DVD, or a Blu-ray Disc).

[0080]In this application, apparatus elements described as having particular attributes or performing particular operations are specifically configured to have those particular attributes and perform those particular operations. Specifically, a description of an element to perform an action means that the element is configured to perform the action. The configuration of an element may include programming of the element, such as by encoding instructions on a non-transitory, tangible computer-readable medium associated with the element.

[0081]The apparatuses and methods described in this application may be partially or fully implemented by a special purpose computer created by configuring a general purpose computer to execute one or more particular functions embodied in computer programs. The functional blocks, flowchart components, and other elements described above serve as software specifications, which can be translated into the computer programs by the routine work of a skilled technician or programmer.

[0082]The computer programs include processor-executable instructions that are stored on at least one non-transitory, tangible computer-readable medium. The computer programs may also include or rely on stored data. The computer programs may encompass a basic input/output system (BIOS) that interacts with hardware of the special purpose computer, device drivers that interact with particular devices of the special purpose computer, one or more operating systems, user applications, background services, background applications, etc.

[0083]The computer programs may include: (i) descriptive text to be parsed, such as HTML (hypertext markup language), XML (extensible markup language), or JSON (JavaScript Object Notation) (ii) assembly code, (iii) object code generated from source code by a compiler, (iv) source code for execution by an interpreter, (v) source code for compilation and execution by a just-in-time compiler, etc. As examples only, source code may be written using syntax from languages including C, C++, C#, Objective-C, Swift, Haskell, Go, SQL, R, Lisp, Java®, Fortran, Perl, Pascal, Curl, OCaml, Javascript®, HTML5 (Hypertext Markup Language 5th revision), Ada, ASP (Active Server Pages), PHP (PHP: Hypertext Preprocessor), Scala, Eiffel, Smalltalk, Erlang, Ruby, Flash®, Visual Basic®, Lua, MATLAB, SIMULINK, and Python®.

[0084]The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.