AIR CONDITIONER UNITS AND METHODS FOR COLD-WEATHER MITIGATION

Description

FIELD OF THE DISCLOSURE

The present subject matter relates generally to air conditioner units, such as single-package air conditioner units, including methods of operating such units in relatively cold ambient environments.

BACKGROUND OF THE DISCLOSURE

Air conditioner units are conventionally utilized to adjust the temperature within structures such as dwellings and office buildings. For instance, one-unit type or single-package room air conditioner units, such as window units, single-package vertical units (SPVU), vertical packaged air conditioners (VPAC), or package terminal air conditioners (PTAC) may be utilized to adjust the temperature in, for example, a single room or group of rooms of a structure. A typical one-unit type air conditioner or air conditioning appliance includes an indoor portion and an outdoor portion. The indoor portion generally communicates (e.g., exchanges air) with the area within a building, and the outdoor portion generally communicates (e.g., exchanges air) with the area outside a building. Accordingly, the air conditioner unit generally extends through, for example, a wall of the structure. Generally, a fan may be operable to rotate to motivate air through the indoor portion. Another fan may be operable to rotate to motivate air through the outdoor portion. A sealed cooling system including a compressor is generally housed within the air conditioner unit to treat (e.g., cool or heat) air as it is circulated through, for example, the indoor portion of the air conditioner unit. One or more control boards are typically provided to direct the operation of various elements of the particular air conditioner unit.

In typical arrangements, the outdoor portion of an air-conditioner unit, including the outdoor heat exchanger, is mounted outside of the building or otherwise in a non-treated space. As a result, the outdoor portion of the air-conditioner unit is subjected to the temperatures and conditions of the ambient environment. In especially cold environments, issues may arise that can affect the performance or longevity of the unit. For example, cold temperatures may lead to undesirable condensing of refrigerant within the sealed cooling system (e.g., “slugging”). In certain instances, condensed refrigerant may even displace a lubricant or oil within the compressor, which in turn may lead to improper operation or damage of the compressor.

Previous attempts have been made to mitigate cold-weather effects, such as by attaching resistive heating elements (e.g., “belly bands”) to the compressor to heat the compressor at a fixed heating rate or power output. Such systems present certain drawbacks, however, such as being cumbersome or expensive to assemble, prone to damage, or ineffective.

As a result, it would be useful to provide an air conditioner unit or methods of operation capable of addressing one or more of the above-identified issues.

BRIEF DESCRIPTION OF THE DISCLOSURE

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 aspect of the present disclosure, an air conditioner unit is provided. The air conditioner unit may include an outdoor heat exchanger, and outdoor fan, an indoor heat exchanger, an indoor fan, a compressor, an outdoor temperature assembly, and a controller. The compressor may be in fluid communication with the outdoor heat exchanger and the indoor heat exchanger to circulate a refrigerant between the outdoor heat exchanger and the indoor heat exchanger. The outdoor temperature assembly may be disposed apart from the indoor heat exchanger and configured to detect an outdoor temperature. The controller may be in operative communication with the compressor and the outdoor temperature assembly. The controller may be configured to initiate a protective operation. The protective operation may include receiving a temperature signal from the outdoor temperature assembly corresponding to the outdoor temperature, determining a heating wattage for the compressor based on the received temperature signal, and heating the compressor according to the determined heating wattage.

In another exemplary aspect of the present disclosure, a method of operating an air conditioner unit is provided. The method may include receiving a temperature signal from an outdoor temperature assembly corresponding to an outdoor temperature. The method may also include determining a heating wattage for a compressor of the air conditioner unit based on the received temperature signal. The method may further include heating the compressor according to the determined heating wattage.

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.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures.

FIG. 1 provides a perspective view of an air conditioner unit, with a room front exploded from a remainder of the air conditioner unit for illustrative purposes, in accordance with exemplary embodiments of the present disclosure.

FIG. 2 is a perspective view of components of an indoor portion of an air conditioner unit in accordance with exemplary embodiments of the present disclosure.

FIG. 3 is a rear perspective view of a bulkhead assembly in accordance with exemplary embodiments of the present disclosure.

FIG. 4 is another perspective view of components of an indoor portion of an air conditioner unit in accordance with exemplary embodiments of the present disclosure.

FIG. 5 provides a schematic view of an air conditioner unit according to exemplary embodiments of the present disclosure.

FIG. 6 provides a flow chart illustrating a method of operating an air conditioner unit according to exemplary embodiments of the present disclosure.

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.

DETAILED DESCRIPTION

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 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. 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.

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”). In addition, here and throughout the specification and claims, range limitations may be combined 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 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, such as, clockwise or counterclockwise, with the vertical direction V).

The terms “upstream” and “downstream” refer to the relative flow direction with respect to fluid flow in a fluid pathway. For example, “upstream” refers to the flow direction from which the fluid flows, and “downstream” refers to the flow direction to which the fluid flows.

Except as explicitly indicated otherwise, recitation of a singular processing element (e.g., “a controller,” “a processor,” “a microprocessor,” etc.) is understood to include more than one processing element. In other words, “a processing element” is generally understood as “one or more processing element.” Furthermore, barring a specific statement to the contrary, any steps or functions recited as being performed by “the processing element” or “said processing element” are generally understood to be capable of being performed by “any one of the one or more processing elements.” Thus, a first step or function performed by “the processing element” may be performed by “any one of the one or more processing elements,” and a second step or function performed by “the processing element” may be performed by “any one of the one or more processing elements and not necessarily by the same one of the one or more processing elements by which the first step or function is performed.” Moreover, it is understood that recitation of “the processing element” or “said processing element” performing a plurality of steps or functions does not require that at least one discrete processing element be capable of performing each one of the plurality of steps or functions.

Aspects of the present disclosure may advantageously prevent or mitigate certain aspects of, for example, operation in cold-weather environments. Certain aspects of the present disclosure may, in particular, prevent sludging or condensing of refrigerant that may otherwise be caused by relatively cold ambient temperatures (e.g., below 0° Celsius). Such aspects may notably be able to effectively respond to a particular environment or unit. Additionally or alternatively, some aspects may notably provide a robust assembly that would prevent excessive wear on the unit or increased parts or steps for an assembly process.

Referring now to the figures, in FIGS. 1 through 5, an air conditioner 10 according to various exemplary embodiments is provided. The air conditioner 10 is generally a one-unit type air conditioner, also conventionally referred to as a room air conditioner or package terminal air conditioner unit (PTAC). The air conditioner 10 includes an indoor portion 12 and an outdoor portion 14, and defines a vertical direction V, a lateral direction L, and a transverse direction T. Each direction V, L, T is perpendicular to each other, such that an orthogonal coordinate system is generally defined.

Although described in the context of a PTAC, an air conditioner unit as disclosed herein may be provided as any suitable air conditioner unit (e.g., wherein at least a portion of a sealed system is configured for installation in or proximal to an outdoor or untreated environment). Such units may include window unit, single-package vertical unit (SPVU), vertical packaged air conditioner (VPAC), or a suitable single-package air conditioner, including heat-pump air conditioner units capable of alternately cooling and heating a corresponding room or indoor environment. The air conditioner 10 is intended only as an exemplary unit and does not otherwise limit the scope of the present disclosure. Thus, it is understood that the present disclosure may be equally applicable to other types of air conditioner units.

Generally, a cabinet 20 of the air conditioner 10 contains various other components of the air conditioner 10. Cabinet 20 may include, for example, a rear grill 22 and a room front 24 that may be spaced apart along the transverse direction T by a wall sleeve 26. The rear grill 22 may be part of the outdoor portion 14, while the room front 24 is part of the indoor portion 12. Components of the outdoor portion 14, such as an outdoor heat exchanger 30, outdoor fan 133 (FIG. 5), and compressor 32 may be housed within the wall sleeve 26. A casing 34 may additionally enclose the outdoor fan.

Referring now also to FIG. 2, indoor portion 12 may include, for example, an indoor heat exchanger 40, a blower fan 42, and a heating unit 44. These components may, for example, be housed behind the room front 24. Additionally, a bulkhead 46 may generally support or house various other components or portions thereof of the indoor portion 12, such as the blower fan 42 and the heating unit 44. Bulkhead 46 may generally separate and define the indoor portion 12 and outdoor portion 14. As would be understood, when air conditioner 10 is mounted within a room or indoor environment (e.g., to heat or cool the room or indoor environment), indoor portion 12 is generally held or enclosed within the indoor environment. Optionally, outdoor portion 14 may be generally held outside of the indoor environment.

Outdoor and indoor heat exchangers 30, 40 may be components of a thermodynamic assembly (i.e., sealed system), which may be operated as a refrigeration assembly (and thus perform a refrigeration cycle) and, in the case of the heat pump unit embodiment, a heat pump (and thus perform a heat pump cycle). Thus, as is understood, exemplary heat pump unit embodiments may be selectively operated perform a refrigeration cycle at certain instances (e.g., while in a cooling mode) and a heat pump cycle at other instances (e.g., while in a heating mode).

In optional embodiments, such as exemplary heat pump unit embodiments, the sealed system includes a reversible refrigerant valve 110 (FIG. 5). Reversible refrigerant valve 110 selectively directs compressed refrigerant from compressor 32 to either indoor heat exchanger 40 or outdoor heat exchanger 30. For example, in a cooling mode, reversible refrigerant valve 110 is arranged or configured to direct compressed refrigerant from compressor 32 to outdoor heat exchanger 30. Conversely, in a heating mode, reversible refrigerant valve 110 is arranged or configured to direct compressed refrigerant from compressor 32 to indoor heat exchanger 40. Thus, reversible refrigerant valve 110 permits the sealed system to adjust between the heating mode and the cooling mode (e.g., as selected at a control panel 87), as will be understood by those skilled in the art.

The sealed system may, for example, further include compressor 32 and an expansion valve, both of which may be in fluid communication with the heat exchangers 30, 40 to flow refrigerant therethrough, as is generally understood. In some embodiments, the compressor 32 may be a variable speed compressor (e.g., multi-winding or three-phase compressor assembly). In this regard, compressor 32 may be operated at various speeds (e.g., depending on the current air conditioning needs of the room and the demand from the sealed system during a conditioning operation). For example, according to an exemplary embodiment, compressor 32 may be configured to operate during a conditioning (e.g., heating, cooling, or dehumidification) operation at any speed between a minimum conditioning speed [e.g., 1500 revolutions per minute (RPM)], to a maximum rated speed (e.g., 3500 RPM).

When the assembly is operating in a cooling mode, and thus performs a refrigeration cycle, the indoor heat exchanger 40 acts as an evaporator and the outdoor heat exchanger 30 acts as a condenser. In heat pump unit embodiments, when the assembly is operating in a heating mode, and thus performs a heat pump cycle, the indoor heat exchanger 40 acts as a condenser and the outdoor heat exchanger 30 acts as an evaporator. The outdoor and indoor heat exchangers 30, 40 may each include coils 31, 41, as illustrated, through which a refrigerant may flow for heat exchange purposes, as is generally understood.

Additionally or alternatively, one or more portions of heat exchangers 30, 40 may be adapted for use as dehumidification features or as part of a dehumidification routine or operation. For instance, when a dehumidification routine is initiated or implemented (e.g., in a cooling mode or heating mode), a refrigeration cycle may be performed while air is directed across at least a portion of indoor heat exchanger 40 to generate a dry airflow, as would be understood. Certain known dehumidification routines may subsequently direct the dried airflow across a separate heating unit (e.g., as part of an active heat dehumidification routine) before the air is flowed to the room. Other known dehumidification routines may subsequently direct the dried air across a relatively hot portion of the sealed system (e.g., as part of a reheat loop dehumidification routine) before the air is flowed to the room. Still other known dehumidification routines may direct the dried air directly to the room without additional heating (e.g., as part of a cool-air dehumidification routine).

Bulkhead 46 may include various peripheral surfaces that define an interior 50 thereof. For example, and additionally referring to FIG. 3, bulkhead 46 may include a first sidewall 52 and a second sidewall 54 which are spaced apart from each other along the lateral direction L. A rear wall 56 may extend laterally between the first sidewall 52 and second sidewall 54.

The rear wall 56 may, for example, include an upper portion 60 and a lower portion 62. Upper portion 60 may for example have a generally curvilinear cross-sectional shape, and may accommodate a portion of the blower fan 42 when blower fan 42 is housed within the interior 50. Lower portion 62 may have a generally linear cross-sectional shape, and may be positioned below upper portion 60 along the vertical direction V. Rear wall 56 may further include an indoor facing surface 64 and an opposing outdoor facing surface. The indoor facing surface 64 may face the interior 50 and indoor portion 12, and the outdoor facing surface 66 may face the outdoor portion 14.

Bulkhead 46 may additionally extend between a top end 61 and a bottom end 63 along vertical axis V. Upper portion 60 may, for example, include top end 61, while lower portion 62 may, for example, include bottom end 63. Bulkhead 46 may additionally include, for example, an air diverter 68, which may extend between the sidewalls 52, 54 along the lateral direction L and through which air may flow.

In exemplary embodiments, blower fan 42 may be a tangential fan. Alternatively, however, any suitable fan type may be used. Blower fan 42 may include a blade assembly 70 and a motor 72. The blade assembly 70, which may include one or more blades disposed within a fan housing 74, may be disposed at least partially within the interior 50 of the bulkhead 46, such as within the upper portion 60. As shown, blade assembly 70 may for example extend along the lateral direction L between the first sidewall 52 and the second sidewall 54. The motor 72 may be connected to the blade assembly 70, such as through the fan housing 74 to the blades via a shaft. Operation of the motor 72 may rotate the blades, thus generally operating the blower fan 42. Further, in exemplary embodiments, motor 72 may be disposed exterior to the bulkhead 46. Accordingly, the shaft may for example extend through one of the sidewalls 52, 54 to connect the motor 72 and blade assembly 70.

In exemplary embodiments, heating unit 44 includes one or more heater banks 80. Each heater bank 80 may be operated as desired to produce heat. In some embodiments, three heater banks 80 may be used, as shown. Alternatively, however, any suitable number of heater banks 80 may be used. Each heater bank 80 may further include at least one heater coil or coil pass 82, such as in exemplary embodiments two heater coils or coil passes 82. Alternatively, other suitable heating elements may be used. As is understood, each heater coil pass 82 may be provided as a resistive heating element configured to generate heat in response to resistance to an electrical current flowed therethrough.

The operation of air conditioner 10 including compressor 32 (and thus the sealed system generally) blower fan 42, outdoor fan 133, heating unit 44, or other suitable components may be controlled by a control board or controller 85. Controller 85 may be in communication (via for example a suitable wired or wireless connection) to such components of the air conditioner 10. By way of example, the controller 85 may include a memory and one or more processing devices such as 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 10. The memory may be a separate component from the processor or may be included onboard within the processor. The memory may represent random access memory such as DRAM, or read only memory such as ROM or FLASH. Generally, the processor executes programming instructions stored in memory.

Air conditioner 10 may additionally include a control panel 87 and one or more user inputs 89, which may be included in control panel 87. The user inputs 89 may be in communication with the controller 85. A user of the air conditioner 10 may interact with the user inputs 89 to operate the air conditioner 10, and user commands may be transmitted between the user inputs 89 and controller 85 to facilitate operation of the air conditioner 10 based on such user commands. A display 88 may additionally be provided in the control panel 87, and may be in communication with the controller 85. Display 88 may, for example be a touchscreen or other text-readable display screen, or alternatively may simply be a light that can be activated and deactivated as required to provide an indication of, for example, an event or setting for the air conditioner 10.

Referring now to FIGS. 1, 4, and 5, optional embodiments include one or more indoor temperature sensors. For instance, a first indoor temperature sensor 92 (e.g., indoor refrigerant temperature sensor) or a second indoor temperature sensor 94 (e.g., indoor ambient temperature sensor) may be disposed within the indoor portion 12, as shown. In additional or alternative embodiments, a third indoor temperature sensor 126 (e.g., indoor outlet temperature sensor) is disposed within the indoor portion 12 (e.g., separately from or in addition to the first or second indoor temperature sensor 92).

Each temperature sensor may be configured to sense the temperature of its surroundings. For example, each temperature sensor may be a thermistor or a thermocouple. The indoor temperature sensors 92, 94, 126 may be in communication with the controller 85, and may transmit temperatures sensed thereby to the controller 85 (e.g., as one or more voltages or signals, which the controller 85 is configured to interpret as temperature values). Optionally, the voltages or signal transmitted to the controller 85 may be transmitted in response to a polling request or signal received by one or more of the indoor temperature sensors 92, 94, 126. For example, a polling request or signal may be transmitted to one or more of the indoor temperature sensors 92, 94, 126 from the controller 85.

First indoor temperature sensor 92 may be disposed proximate the indoor heat exchanger 40 (such as relative to the second indoor temperature sensor 94). For example, first indoor temperature sensor 92 may be in contact with the indoor heat exchanger 40, such as with a coil 41 thereof. The first indoor temperature sensor 92 may be configured to detect a temperature for the indoor heat exchanger 40. Second indoor temperature sensor 94 may be spaced from the indoor heat exchanger 40, such as in the transverse direction T. For example, the second indoor temperature sensor 94 may be in contact with the room front 24, as illustrated in FIG. 1. Second indoor temperature sensor 94 may be configured to detect a temperature of air entering the indoor portion 12. Third indoor temperature sensor 126 may be spaced apart from and disposed downstream the first indoor temperature sensor 92 or the second indoor temperature sensor 94. For example, the third indoor temperature sensor 126 may be attached to or in contact with the air diverter 68. The third indoor temperature sensor 126 may be configured to detect a temperature for air exiting the indoor portion 12. During certain operations (e.g., cooling operations), air may thus generally flow across or adjacent to the second indoor temperature sensor 94, the first indoor temperature sensor 92, and then the third indoor temperature sensor 126.

Generally, one or more outdoor temperature assemblies, which may be spaced apart from the indoor portion 12 or indoor heat exchanger 30 and configured to detect an ambient or outdoor temperature, may be provided.

Referring especially to FIGS. 1 and 5, in some embodiments, the outdoor temperature assemblies include or are provided as a first outdoor temperature sensor 132 (e.g., outdoor refrigerant temperature sensor) or a second outdoor temperature sensor 134 (e.g., outdoor ambient temperature sensor). The first outdoor temperature sensor 132 or the second outdoor temperature sensor 132 may be disposed within the outdoor portion 14 (e.g., separately from or in addition to the indoor temperature sensors 92, 94, 126). Each temperature sensor may be configured to sense the temperature of its surroundings. For example, each temperature sensor may be a thermistor or a thermocouple. The outdoor temperature sensors 132, 134 may be in communication with the controller 85, and may transmit temperatures sensed thereby to the controller 85 (e.g., as one or more temperature signals or voltage signals, which the controller 85 is configured to interpret as temperature readings).

First outdoor temperature sensor 132 may be disposed proximate the outdoor heat exchanger 30 (such as relative to the second outdoor temperature sensor 134). For example, in some embodiments, first outdoor temperature sensor 132 may be in contact with the outdoor heat exchanger 30, such as with a coil 31 (FIG. 1) thereof. The first outdoor temperature sensor 132 may be configured to detect a temperature for the outdoor heat exchanger 30. Second outdoor temperature sensor 134 may be spaced from the outdoor heat exchanger 30, such as in the transverse direction T. For example, the second outdoor temperature sensor 134 may be in contact with the rear grill 22 (FIG. 1). The second outdoor temperature sensor 134 may be configured to detect a temperature for air entering or surrounding the outdoor portion 14.

In some embodiments, one or more remote devices 202, such as a remote temperature sensor 210 or computer 240 (e.g., personal computer, laptop, server, smartphone, tablet, etc.), are provided at a location separate and apart from the cabinet 20. In particular, one or more remote devices 202 may be included with or provided as outdoor temperature assemblies.

Generally, each remote device 202 may be spaced apart from cabinet 20 while a corresponding remote controller of the remote device 202 is in operative communication with, and may thus exchange signals to/from, the controller 85 (e.g., via for example a suitable wired or wireless connection). Optionally, the remote device 202 may be positioned within the same general environment (e.g., neighborhood, city, or county) or be otherwise configured to evaluate the environment in which the outdoor portion 14 is located. Additionally or alternatively, the remote device 202 may be independently movable relative to the cabinet 20.

In optional embodiments, a remote temperature sensor 210 is in operative communication with the controller 85 to selectively detecting an outdoor temperature for an area proximal to outdoor portion 14 and which is not actively heated or cooled (e.g., by an air conditioner unit). Thus, the remote temperature sensor 210 includes a remote body 212 that houses or supports a suitable temperature circuit 214 for detecting temperature. For instance, the remote temperature sensor 210 may include a temperature circuit 214 that is or includes one or more thermocouples, thermistors, optical temperature sensors, infrared temperature sensors, etc. Within the remote body 212, a secondary controller 216 may be provided (e.g., in communication with or as part of temperature circuit 214). In additional or alternative embodiments, a network interface 218 may be mounted within the remote body 212 (e.g., to selectively communicate with the controller 85).

The secondary controller 216 may include one or more memory devices and one or more processors. The processors of the secondary controller 216 can be any combination of general or special purpose processors, CPUs, or the like that can execute programming instructions or control code associated with operation of remote temperature sensor 210. The memory devices (i.e., memory) of the secondary controller 216 may represent random access memory such as DRAM or read only memory such as ROM or FLASH. In certain embodiments, the processor of the secondary controller 216 executes programming instructions stored in the memory of the secondary controller 216. The memory of the secondary controller 216 may be a separate component from the processor or may be included onboard within the processor. Alternatively, the secondary controller 216 may be constructed without using a processor, for example, using a combination of discrete analog 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 optional embodiments, the secondary controller 216 includes a network interface 218 (e.g., on or off board for secondary controller 216) such that secondary controller 216 can connect to and communicate over one or more networks (e.g., wireless communications network 220) with the controller 85. In some such embodiments, network interface 218 includes one or more transmitting, receiving, or transceiving components for transmitting/receiving communications with the controller 85 via wireless communications network 220. In exemplary embodiments, the wireless communications network 220 may be a wireless sensor network (such as a Bluetooth communication network), a wireless local area network (WLAN), a point-to point communication networks (such as radio frequency identification networks, near field communications networks, etc.), or a combination of two or more of the above communications networks.

In certain embodiments, the secondary controller 216 is configured to transmit (e.g., wirelessly transmit) one or more detected temperature values (i.e., signals corresponding to a value of a temperature detected at remote temperature sensor 210) to the controller 85. For example, the secondary controller 216 may be configured to transmit detected temperature values unprompted by any outside request, such as a polling request that might otherwise be transmitted to the secondary controller 216 from the controller 85. Thus, the secondary controller 216 may determine to transmit remote temperature values independently of the controller 85 or any other device. The receipt of remote temperature values by the controller 85 may be entirely passive or unprompted by the controller 85. In some such embodiments, the remote temperature values from the secondary controller 216 are transmitted asynchronously or, alternatively, according to a predetermined transmission schedule (e.g., programmed within the secondary controller 216).

As an alternative or supplement to remote temperature sensor 210, one or more remote servers computers 240 may be in operative communication with controller 85 and be configured to selectively transmit an outdoor temperature signal thereto. In some such embodiments, the temperature is transmitted from the remote computer 240 based on value provided by a separate weather service—as is generally understood.

Referring now to FIG. 6, the present disclosure may further be directed to methods (e.g., method 600) of operating an air conditioner or air conditioning appliance, such as air conditioner 10. In exemplary embodiments, the controller 85 may be operable to perform various steps of a method in accordance with the present disclosure.

The methods (e.g., 600) may occur as, or as part of, a protective operation (e.g., separate from a cooling, heating, or dehumidification operation intended to adjust the conditions of a corresponding room) of the air conditioner 10. In particular, the methods disclosed herein may advantageously prevent sludging or condensing of refrigerant that may otherwise be caused by relatively cold ambient temperatures (e.g., below 0° Celsius). Additionally or alternatively, Additionally or alternatively, the methods (e.g., 600) may advantageously prevent excessive wear on the unit or increased parts or steps for an assembly process. Except as otherwise indicated, one or more steps in the below methods (e.g., 600) may be changed, rearranged, performed in a different order, or otherwise modified without deviating from the scope of the present disclosure.

At 610, the method 600 includes receiving a temperature signal corresponding to an outdoor temperature. Specifically, the temperature signal is received from an outdoor temperature assembly so as to provide an indication of the outdoor or ambient temperature. As described above, the outdoor temperature assembly may be provided as a discrete temperature sensor mounted on or within the outdoor portion of the air conditioner unit. Thus, the outdoor temperature signal may correspond to the temperature measured at the cabinet. Additionally or alternatively, the outdoor temperature assembly may be provided as or include a remote temperature sensor spaced apart from the cabinet of the air conditioner unit (e.g., such that the temperature signal is received wirelessly at the controller of the air conditioner unit). Further additionally or alternatively, the outdoor temperature assembly may include or be provided as a remote computer or server configured to detect or transmit the temperature signal (e.g., as provided by a separate weather service). The temperature signal may be received unprompted from the air conditioner unit or, alternatively, in response to a polling signal transmitted to the outdoor temperature assembly. Additionally or alternatively, the temperature signal may be received according to a predetermined rate, schedule, or interval or further in response to another predetermined condition.

As would be understood, the temperature signal may include or be interpreted as a temperature value. Thus, an outdoor temperature value may be determined according to the temperature signal such that a measurement for the outdoor temperature is ascertained.

At 620, the method 600 includes determining a heating wattage for the compressor. Thus, a power rating or value (e.g., in Watts) for heating the compressor of the air conditioner unit may be determined. The determination may be based, for instance, on the received temperature signal of 610. In some embodiments, the determination includes using the received temperature signal (e.g., a temperature value corresponding to the same) as an input for an output heating wattage value. As an example, the heating wattage may be calculated using a predetermined function, graph, or look-up table. The predetermined function, graph, or look-up table may thus correlate one or more outdoor temperature values to one or more corresponding heating wattage values. Such calculations would generally be understood in light of the present disclosure and may be derived from empirical testing or predicted attributes (e.g., determined according to a prototypical or representative unit). Moreover, the predetermined function, graph, or look-up table may be programmed into the air conditioner unit (e.g., controller), such as during assembly of the air conditioner unit.

At 630, the method 600 includes heating the compressor following 620. Specifically, the heating at 630 may be based on 620. In other words, 630 may be based, at least in part, on the determined heating wattage.

In some embodiments, 630 includes directing a heating current (e.g., electrical current) to the compressor (e.g., to travel through the motor of the same). The heating current may be an alternating or AC current, as would be understood, such as in the context of a variable speed compressor.

In certain embodiments heating current is calculated prior to being directed to the compressor. In other words, a value for the heating current (e.g., in Amperes) may be calculated such that the heating current is directed to the compressor at the calculated value. The calculation of the heating current may be based on the determined heating wattage (e.g., at 620) and at least one resistance value of the compressor. For instance, if power (e.g., determined wattage) is represented as P, while compressor resistance is represented as R and current is represented as I, the power draw of exemplary compressors may be expressed as

( P = 3 2 ⁢ R · I 2 )

and, in turn, the heating current may be calculated as

( I = 2 3 ⁢ P R ) .

The resistance value of the compressor (i.e., R, in Ohms) may be determined prior to calculation of the heating current. In some embodiments, the resistance value is a predetermined, fixed value programmed within the controller (e.g., during assembly). In alternative embodiments, the resistance value is measured directly on the unit. For instance, as part of 630, the method 600 may further include measuring resistance across the compressor to determine the resistance value (e.g., prior to directing the heating current to the compressor or in response to 610 or 620). Measuring resistance is generally understood and may include, for instance, directing a reference current through or across the compressor and measuring the voltage drop across the same.

In some embodiments, the heating current is directed at a fixed frequency. The fixed frequency may be a set or predetermined frequency value (e.g., in Hertz). The fixed frequency may be set significantly lower than the frequencies used for conditioning operations (i.e., used to rotate the variable speed compressor motor at conditioning speeds during heating, cooling, or dehumidification operations). For instance, the fixed frequency may be less than or equal to 10 Hertz (e.g., between 0.1 and 1 Hertz). In some embodiments, the fixed frequency is configured to rotate the compressor at a sub-compression speed, such that the speed is insufficient to compress refrigerant through the sealed system. For instance, the fixed frequency may be configured to target a rotation speed below 10 revolutions per minute (RPM) (e.g., between 1 and 10 RPM). Nonetheless, the heating current may be directed as an open loop input, such that the heating current is not dependent on an actual or measured speed of the compressor. Notably, the low fixed frequency of the heating current may promote an even load across multiple phases or windings of the compressor (e.g., in turn helping prevent excessive wear of the compressor).

Generally, 630 will continue until a predetermined condition is met. In optional embodiments, direction of the heating current may continue until a heating or cooling demand signal is received (e.g., indicating the need to heat or cool the corresponding room for the unit as part of a conditioning operation, as would be understood).

This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.