Condensate Management System for an Air Conditioner Appliance

The present disclosure relates generally to air conditioner units, and more particularly to condensate management within packaged terminal air conditioner units.

Air conditioner or conditioning units are conventionally utilized to adjust the temperature indoors, e.g., within structures such as dwellings and office buildings. Such units commonly include a closed refrigeration loop to heat or cool the indoor air. Typically, the indoor air is recirculated while being heated or cooled. A variety of sizes and configurations are available for such air conditioner units. For example, some units may have one portion installed indoors that is connected to another portion located outdoors, e.g., by tubing or conduit carrying refrigerant. These types of units are typically used for conditioning the air in larger spaces.

Another type of air conditioner unit, commonly referred to as single-package vertical units (SPVU) or package terminal air conditioners (PTAC), may be utilized to adjust the temperature in somewhat smaller indoor spaces, for example, a single room or group of rooms of a structure. These units typically operate like split heat pump systems, except that the indoor and outdoor portions are defined by a bulkhead and all system components are housed within a single package that installed in a wall sleeve positioned within an opening of an exterior wall of a building.

However, SPVU and PTAC units are often exposed to outdoor ambient temperatures that are below or well below freezing. In addition, condensate is commonly directed to the outdoor portions of these units where the cool temperatures may result in water freezing within the base pan. The freezing water may prevent the egress of condensate from the base pan and the resulting ice and water build-up can strike or lock up the fan and can even crush copper tubes. Full metal base pans are less prone to this issue, but they are expensive, heavy, and can cause new thermal issues by allowing undesirable heat transfer.

Accordingly, improved air conditioner units that are less prone to issues associated with freezing condensate would be useful. More specifically, an air conditioner unit that facilitates improved condensate management would be particularly beneficial.

Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.

In one exemplary embodiment, an air conditioner unit defining a vertical, a lateral, and a transverse direction is provided, including a bulkhead defining an indoor portion and an outdoor portion, an indoor heat exchanger positioned within the indoor portion, an outdoor heat exchanger positioned within the outdoor portion, a base pan positioned under the outdoor heat exchanger for collecting condensate that drips off the outdoor heat exchanger, a wall sleeve defining a mechanical compartment configured for receiving at least a portion of the base pan, the indoor heat exchanger, and the outdoor heat exchanger, and a thermal distributor element mounted within the base pan and defining a top surface and a bottom surface, wherein the top surface at least partially defines a condensate collection reservoir and the bottom surface is positioned within a gap defined between the base pan and the wall sleeve.

In another exemplary embodiment, a condensate management system for an air conditioner unit is provided. The air conditioner unit includes a bulkhead mounted within a cabinet to define an indoor portion and an outdoor portion, an indoor heat exchanger positioned within the indoor portion, and an outdoor heat exchanger positioned within the outdoor portion. The condensate management system includes a base pan positioned under the outdoor heat exchanger for collecting condensate that drips off the outdoor heat exchanger, a wall sleeve defining a mechanical compartment configured for receiving at least a portion of the base pan, the indoor heat exchanger, and the outdoor heat exchanger, and a thermal distributor element mounted within the base pan and defining a top surface and a bottom surface, wherein the top surface at least partially defines a condensate collection reservoir and the bottom surface is positioned within a gap defined between the base pan and the wall sleeve.

These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present invention.

Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

As used herein, the terms “first,” “second,” and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components. The terms “includes” and “including” are intended to be inclusive in a manner similar to the term “comprising.” Similarly, the term “or” is generally intended to be inclusive (i.e., “A or B” is intended to mean “A or B or both”). The term “at least one of” in the context of, e.g., “at least one of A, B, and C” refers to only A, only B, only C, or any combination of A, B, and C. In addition, here and throughout the specification and claims, range limitations may be combined and/or interchanged. Such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise. For example, all ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other. The singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise.

Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “generally,” “about,” “approximately,” and “substantially,” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value, or the precision of the methods or machines for constructing or manufacturing the components and/or systems. For example, the approximating language may refer to being within a 10 percent margin, i.e., including values within ten percent greater or less than the stated value. In this regard, for example, when used in the context of an angle or direction, such terms include within ten degrees greater or less than the stated angle or direction, e.g., “generally vertical” includes forming an angle of up to ten degrees in any direction, e.g., clockwise or counterclockwise, with the vertical direction V.

The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” In addition, references to “an embodiment” or “one embodiment” does not necessarily refer to the same embodiment, although it may. Any implementation described herein as “exemplary” or “an embodiment” is not necessarily to be construed as preferred or advantageous over other implementations. Moreover, each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

provides an exploded perspective view of a packaged terminal air conditioner unitaccording to example embodiments of the present disclosure. Generally, packaged terminal air conditioner unitis operable to generate chilled and/or heated air in order to regulate the temperature of an associated room or building. As will be understood by those skilled in the art, packaged terminal air conditioner unitmay be utilized in installations where split heat pump systems are inconvenient or impractical. As illustrated, packaged terminal air conditioner unitdefines a vertical direction V, a lateral direction L, and a transverse direction T that are mutually perpendicular and form an orthogonal direction system.

As used herein, the term “packaged terminal air conditioner unit” is applied broadly, and the present subject matter is not limited to the specific constructions described and illustrated herein. For example, although aspects of the present subject matter are described with reference to PTAC unit, it should be appreciated that aspects of the present subject matter may be equally applicable to other air conditioner unit types and configurations, such as single package vertical units (SPVUs) and split heat pump systems.

As discussed in greater detail below, air conditioner unitmay include a sealed system(i.e., sealed heat exchange system) to facilitate heat transfer and conditioning of a room where air conditioner unitis located. Sealed systemincludes components for transferring heat between the exterior atmosphere and the interior atmosphere, as discussed in greater detail below. In general, air conditioner unitmay be a self-contained or autonomous system for heating and/or cooling air.

According to an example embodiment, sealed systemand other components of air conditioner unitmay be disposed within a wall sleeveof air conditioner unit. In general, wall sleevemay be a structural frame that extends between an interior side portionand an exterior side portion. Interior side portionof wall sleeveand exterior side portionof wall sleeveare spaced apart from each other along the transverse direction T. Thus, interior side portionof wall sleevemay be positioned at or contiguous with an interior atmosphere of the room being conditioned, and exterior side portionof wall sleevemay be positioned at or contiguous with an exterior atmosphere (e.g., the outside ambient environment).

As shown, wall sleevemay generally define an internal volume or a mechanical compartment. Sealed systemis disposed or positioned within mechanical compartmentof wall sleeve. A front paneland a rear grill or screenhinder or limit access to mechanical compartmentof wall sleeve. Front panelis positioned at or adjacent interior side portionof wall sleeve, and rear screenis mounted to wall sleeveat exterior side portionof wall sleeve. Front paneland rear screeneach define a plurality of holes that permit air to flow through front paneland rear screen, with the holes sized for preventing foreign objects from passing through front paneland rear screeninto mechanical compartmentof wall sleeve.

Air conditioner unitalso includes a drain pan, a bottom tray, or a base panthat sits within wall sleeveand supports various components of sealed systemand air conditioner unit. As discussed in more detail below, base panmay include various features to facilitate condensate management within air conditioner unit. For example, because sealed systemis positioned on base pan, liquid runoff from sealed system(e.g., collected condensate) may flow into and collect within base pan. Air conditioner unitmay include additional features to discharge the collected condensate, prevent the collected condensate from freezing, or otherwise effectively manage the collected condensate.

Air conditioner unitmay further include an inner wall or bulkheadpositioned within mechanical compartmentof wall sleeve. Bulkheadmay be mounted to base panand extends upwardly from base panto a top wall of wall sleeve. Bulkheadlimits or prevents air flow between interior side portionof wall sleeveand exterior side portionof wall sleevewithin mechanical compartmentof wall sleeve. Thus, bulkheadmay divide mechanical compartmentof wall sleeve. Specifically, bulkheadmay generally separate and define an indoor portionand an outdoor portion.

In general, during installation of air conditioner unit, wall sleeveis first mounted within an opening defined within a building wall, e.g., using any suitable mechanical fastener, welding, adhesive, etc. In addition, the joint between wall sleeveand the building wall may be sealed using any suitable caulk, sealant, etc. Bulkhead, sealed system, and other components of air conditioner unitare then mounted at least partially within wall sleeve. Wall sleevemay generally be constructed of any suitable number of layers and/or materials, e.g., to provide structural rigidity necessary to support components of package terminal air conditioner unitwhile achieving the desired sound damping. In this regard, for example, wall sleevemay include a stamped metal layer, e.g., formed from stainless steel, painted external steel, or any other suitably rigid material, such as a rigid plastic.

provides a perspective view of certain components of air conditioner unit, including sealed system. In addition,provides a schematic view of air conditioner unit. As shown, sealed systemincludes a compressor, an interior heat exchanger or coiland an exterior heat exchanger or coil. As is generally understood, compressoris generally operable to circulate or urge a flow of refrigerant through sealed system, which may include various conduits which may be utilized to flow refrigerant between the various components of sealed system. Thus, indoor heat exchangerand outdoor heat exchangermay be between and in fluid communication with each other and compressor.

As will be described in further detail below, sealed systemmay operate in a cooling mode and, alternately, a heating mode. During operation of sealed systemin the cooling mode, refrigerant generally flows from indoor heat exchangerand to compressor. During operation of sealed systemin the heating mode, refrigerant generally flows from outdoor heat exchangerand to compressor. As will be explained in more detail below, a compression reversing valvein fluid communication with compressormay control refrigerant flow to and from compressor, as well as the coils,.

During operation of sealed systemin the cooling mode, refrigerant flows from indoor heat exchangerand to compressor. For example, refrigerant may exit indoor heat exchangeras a fluid in the form of a superheated vapor. Upon exiting indoor heat exchanger, the refrigerant may enter compressor, which is operable to compress the refrigerant. Accordingly, the pressure and temperature of the refrigerant may be increased in compressorsuch that the refrigerant becomes a more superheated vapor.

Outdoor heat exchangeris disposed downstream of compressorin the cooling mode and acts as a condenser. Thus, outdoor heat exchangeris operable to reject heat into the exterior atmosphere at exterior side portionof wall sleevewhen sealed systemis operating in the cooling mode. For example, the superheated vapor from compressormay enter outdoor heat exchangervia a first distribution conduit() that extends between and fluidly connects compression reversing valveand outdoor heat exchanger. Within outdoor heat exchanger, the refrigerant from compressortransfers energy to the exterior atmosphere and condenses into a saturated liquid and/or liquid vapor mixture. An exterior air handler or outdoor fan() is positioned adjacent outdoor heat exchangerand may facilitate or urge a flow of air from the exterior atmosphere across outdoor heat exchangerin order to facilitate heat transfer.

According to the illustrated embodiment, an expansion device or a variable electronic expansion valvemay be further provided to regulate refrigerant expansion. Specifically, variable electronic expansion valveis disposed along a fluid conduitthat extends between indoor heat exchangerand outdoor heat exchanger. During use, variable electronic expansion valvemay generally expand the refrigerant, lowering the pressure and temperature thereof. In the cooling mode, refrigerant, which may be in the form of high liquid quality/saturated liquid vapor mixture, may exit outdoor heat exchangerand travel through variable electronic expansion valvebefore flowing through indoor heat exchanger. In the heating mode, refrigerant may exit indoor heat exchangerand travel through variable electronic expansion valvebefore flowing to outdoor heat exchanger. As described in more detail below, variable electronic expansion valveis generally configured to be adjustable. In other words, the flow (e.g., volumetric flow rate in milliliters per second) of refrigerant through variable electronic expansion valvemay be selectively varied or adjusted.

Indoor heat exchangeris disposed downstream of variable electronic expansion valvein the cooling mode and acts as an evaporator. Thus, indoor heat exchangeris operable to heat refrigerant within indoor heat exchangerwith energy from the interior atmosphere at interior side portionof wall sleevewhen sealed systemis operating in the cooling mode. For example, the liquid or liquid vapor mixture refrigerant from variable electronic expansion valvemay enter indoor heat exchangervia fluid conduit. Within indoor heat exchanger, the refrigerant from variable electronic expansion valvereceives energy from the interior atmosphere and vaporizes into superheated vapor and/or high-quality vapor mixture. An interior air handler or indoor fan() is positioned adjacent indoor heat exchangerand may facilitate or urge a flow of air from the interior atmosphere across indoor heat exchangerin order to facilitate heat transfer. From indoor heat exchanger, refrigerant may return to compressorfrom compression reversing valve, e.g., via a second conduit() that extends between and fluidly connects indoor heat exchangerand compression reversing valve.

During operation of sealed systemin the heating mode, compression reversing valvereverses the direction of refrigerant flow from compressor. Thus, in the heating mode, indoor heat exchangeris disposed downstream of compressorand acts as a condenser, e.g., such that indoor heat exchangeris operable to reject heat into the interior atmosphere at interior side portionof wall sleeve. In addition, outdoor heat exchangeris disposed downstream of variable electronic expansion valvein the heating mode and acts as an evaporator, e.g., such that outdoor heat exchangeris operable to heat refrigerant within outdoor heat exchangerwith energy from the exterior atmosphere at exterior side portionof wall sleeve.

Accordingly, as is understood in the art, sealed systemmay be alternately operated as a refrigeration assembly (and thus perform a refrigeration cycle) or a heat pump (and thus perform a heat pump cycle). As shown in, when sealed systemis operating in a cooling mode and thus performing a refrigeration cycle, the indoor heat exchangeracts as an evaporator and the outdoor heat exchangeracts as a condenser. Alternatively, when the assembly is operating in a heating mode and thus performs a heat pump cycle, the indoor heat exchangeracts as a condenser and the outdoor heat exchangeracts as an evaporator. The outdoor and indoor heat exchangers,may each include coils through which a refrigerant may flow for heat exchange purposes, as is generally understood.

In addition, sealed systemmay be operated in a defrost mode, e.g., to remove frost from outdoor heat exchanger, particularly when the ambient temperature is low. In this regard, in the defrost mode, sealed systemis configured to urge hot refrigerant directly into outdoor heat exchanger, e.g., by adjusting the operation of compressorand compressions reversing valve. This hot refrigerant causes any frozen condensate on the coils of outdoor heat exchanger to melt and fall off into base pan.

Referring again to, air conditioner unitmay additionally include a control paneland one or more user inputs, which may be included in control panel. A displaymay additionally be provided in the control panel, such as a touchscreen or other text-readable display screen. Alternatively, displaymay simply be a light that can be activated and deactivated as required to provide an indication of, for example, an event or setting for air conditioner unit. The user inputsand/or displaymay be in communication with the controller. A user of air conditioner unitmay interact with the user inputsto operate air conditioner unit, and user commands may be transmitted between the user inputsand controllerto facilitate operation of air conditioner unitbased on such user commands.

Controllermay regulate operation of air conditioner unit, e.g., responsive to sensed conditions and user input from control panel. Thus, controlleris operably coupled to various components of air conditioner unit, such as control panel, components of sealed system, and/or a temperature sensor (not shown), such as a thermistor or thermocouple, for measuring the temperature of the interior atmosphere. In particular, controllermay selectively activate sealed systemin order to chill or heat air within sealed system, e.g., in response to temperature measurements from the temperature sensor.

In some embodiments, controllerincludes memory and one or more processing devices. For instance, the processing devices may be microprocessors, CPUs or the like, such as general or special purpose microprocessors operable to execute programming instructions or micro-control code associated with operation of air conditioner unit. The memory can represent random access memory such as DRAM, or read only memory such as ROM or FLASH. The processor executes programming instructions stored in the memory. The memory can be a separate component from the processor or can be included onboard within the processor. Alternatively, controllermay be constructed without using a microprocessor, e.g., using a combination of discrete analog and/or digital logic circuitry (such as switches, amplifiers, integrators, comparators, flip-flops, AND gates, and the like) to perform control functionality instead of relying upon software.

In order to facilitate operation of sealed systemand other components of air conditioner unit, air conditioner unitmay include a variety of sensors for detecting conditions internal and external to air conditioner unit. These conditions can be fed to controllerwhich may make decisions regarding operation of air conditioner unit. For example, as best illustrated in, air conditioner unitmay include an ambient temperature and/or humidity sensorwhich is positioned and configured for measuring the outdoor or ambient temperature and/or humidity. According to exemplary embodiments, air conditioner unitmay further include an indoor temperature/humidity sensor for measuring indoor conditions temperatures.

As used herein, “temperature sensor” or the equivalent is intended to refer to any suitable type of temperature measuring system or device positioned at any suitable location for measuring the desired temperature. Thus, for example, temperature sensormay each be any suitable type of temperature sensor, such as a thermistor, a thermocouple, a resistance temperature detector, a semiconductor-based integrated circuit temperature sensor, etc. In addition, temperature sensormay be positioned at any suitable location and may output a signal, such as a voltage, to a controller that is proportional to and/or indicative of the temperature being measured. Although exemplary positioning of temperature sensors is described herein, it should be appreciated that air conditioner unitmay include any other suitable number, type, and position of temperature, and/or other sensors according to alternative embodiments.

As used herein, the terms “humidity sensor” or the equivalent may be intended to refer to any suitable type of humidity measuring system or device positioned at any suitable location for measuring the desired humidity. Thus, for example, humidity sensormay refer to any suitable type of humidity sensor, such as capacitive digital sensors, resistive sensors, and thermal conductivity humidity sensors. In addition, humidity sensormay be positioned at any suitable location and may output a signal, such as a voltage, to a controller that is proportional to and/or indicative of the humidity being measured. Although exemplary positioning of humidity sensors is described herein, it should be appreciated that unitmay include any other suitable number, type, and position of humidity sensors according to alternative embodiments.

Referring now also generally to, a water or condensate management systemof air conditioner unitwill be described according to example embodiments of the present subject matter. In this regard, as explained briefly above, operation of air conditioner unitmay generally result in the formation of condensate or water melted off the heat exchanger coils that must be collected, discharged, or otherwise managed in air conditioner unit. For example, when air conditioner unitis operating in the heat pump mode, condensate may tend to form on outdoor heat exchanger. In addition, during the defrost mode, ice and/or frost may be melted off outdoor heat exchanger. This condensate may collect below outdoor heat exchanger. Notably, in very cold ambient temperatures, this condensate may tend to freeze before it exits the unit, thereby preventing further egress of collected condensate and buildup of ice that may affect operation of air conditioner unit(e.g., such as by stalling outdoor fanor crushing heat exchanger coils). Accordingly, condensate management systemmay include one or more features that facilitate improved management of collected condensate.

According to an example embodiment, condensate management systemmay be defined by or otherwise associated with base pan. In this regard, base panis generally positioned under outdoor heat exchanger. In addition, a condensate collection reservoirmay be defined by base panor may be positioned on base pan. In this manner, condensate that drips from outdoor heat exchangermay be collected within condensate collection reservoirand may be routed outside of air conditioner unit. Specifically, as shown for example in, base panmay generally define one or more pan holesthat pass through base panalong the vertical direction V from a top surfaceto a bottom surfaceof base pan. Specifically, as illustrated, pan holesmay be defined within condensate collection reservoirto facilitate egress of condensate in a desired location through base pan.

As best illustrated in, base panmay generally be mounted within wall sleeve. Moreover, wall sleeveand/or base panmay define structural supports, support feet, or other suitable structure for securing base panwithin wall sleeve. Moreover, these features may define a gapbetween bottom surfaceof base panand a top surfaceof a lower wallof wall sleeve. In general, gapmay be suitably sized for facilitating the discharge of condensate through gapand out one or more discharge aperturesdefined on the exterior side portionof wall sleeve. Accordingly, during operation of sealed system, condensate may fall off outdoor heat exchangerwhere it is collects in condensate collection reservoir, passes through pan holes, and flows through gapbefore being discharged through discharge apertures.

Notably, conventional air conditioner units include base pans that poorly regulate the flow of condensate, particularly in the routing of the condensate to the outside of the unit without permitting it to freeze and affect unit operation. Accordingly, aspects of the present subject matter are directed to a base pan assemblywith improved condensate management. In this regard, for example, base pan assemblymay include base panand an elevated wallthat extends upward from base panalong the vertical direction V to collectively define condensate collection reservoir.

According to an example embodiment, elevated wallmay be formed within or attached to base panin any suitable manner. For example, elevated wallmay be integrally formed with base pan, e.g., using an injection molding process. According to alternative embodiments, elevated wallmay be a separate component that is attached to base panin any suitable manner, e.g., using mechanical fasteners, friction welding, adhesives, etc. According to still other embodiments, elevated wallmay be a defined extension of an outdoor fan shroudor may be mounted directly to outdoor heat exchanger. Other constructions are possible and within the scope of the present subject matter.

Notably, the size and shape of elevated walladdresses issues with condensate management issues that are common to conventional air conditioner units. For example, the size, geometry, and relative dimensions of elevated walland the condensation collection reservoirthat it defines reduce or eliminate the issues with freezing condensate in a novel and inventive manner. However, although a specific geometry is described herein, it should be appreciated that variations and modifications may be made to base pan assemblywhile remaining within the scope of the present subject matter.

For example, according to an example embodiment of the present subject matter, condensate collection reservoirdefines a reservoir footprint (e.g., identified by reference numeralin) in a horizontal plane (e.g., as defined by the lateral direction L and the transverse direction T). In addition, outdoor heat exchangerdefines a heat exchanger footprint (e.g., identified generally by reference numeralin) in the horizontal plane. According to an example embodiment, reservoir footprintis less than 10 times, less than 5 times, less than 3 times, less than 2 times, less than 1.5 times, or less than heat exchanger footprint. Notably, such a small relative footprint retains the condensate within an area immediately proximate to outdoor heat exchanger, which may be warm from the defrost cycle while condensate is draining, thereby minimizing the likelihood of the condensate freezing.

In addition, as illustrated, elevated wallmay fully enclose outdoor heat exchangerwithin a horizontal plane. In this regard, elevated wallmay fully encircle outdoor heat exchangersuch that outdoor heat exchangerfits entirely within condensate collection reservoirin a horizontal plane. For example, elevated wallmay be continuous along a width of outdoor heat exchanger. According to an example embodiment, a portion of elevated wallmay be defined by a perimeter of base pan. Other constructions are possible and within the scope of the present subject matter.

In addition, to avoid the potential for condensate freezing and binding outdoor fan, elevated wallmay be positioned between outdoor heat exchangerand outdoor fan. In this regard, elevated wallmay be positioned such that condensate collection reservoiris spaced apart from the operating region of outdoor fan. Similarly, elevated wallmay be positioned such that condensate collection reservoiris positioned entirely in front of or spaced apart from fan shroud.

According to an example embodiment, elevated wallmay also define a height (not labeled) that is greater than 2 millimeters, greater than 5 millimeters, greater than 10 millimeters, or greater. This may be advantageous for ensuring that the volume of condensate generated during a defrost cycle may be retained within condensate collection reservoirand directed through a pan holepositioned within elevated wall.

According to the embodiment illustrated in, condensate management systemmay further include one or more valves that are operably coupled to pan holesfor selectively regulating the flow of water or condensate therethrough. In this regard, a thermostatic drain valvemay be operably coupled with each pan hole. When ambient temperatures are relatively high and the risk of condensate freezing is low, thermostatic drain valvemay remain closed. By contrast, when temperatures are relatively low and freezing is likely, thermostatic drain valvemay open to quickly and effectively discharge condensate from within condensate collection reservoir.

Notably, according to an example embodiment, base panmay be formed from a plastic material, which may have a relatively low thermal conductivity. As a result, collected condensate may have a tendency to freeze, particularly at locations away from outdoor heat exchanger. In this regard, the condensate dripping from outdoor heat exchangermay begin cooling as soon as it drips from the coils and may continue to cool as it travels through condensate collection reservoirtoward pan holes. Notably, conventional base pans include long and tortuous paths between the outdoor heat exchanger and drain holes, resulting in frequent freezing of condensate and operability issues, particularly in environments with low ambient temperatures.

Accordingly, aspects of the present subject matter may be directed to a condensate collection reservoirthat is localized around outdoor heat exchangerand provides a short path to pan holesfor condensate egress from the unit. In this regard, for example, condensate collection reservoirmay be positioned directly below outdoor heat exchangerand pan holesmay pass through base panwithin condensate collection reservoir. For example, pan holesmay be positioned such that the condensate flows unimpeded to pan holesafter falling from outdoor heat exchanger. In this regard, for example, elevated wallmay be designed to minimize redirection or diversion of the flow of condensate.