HIGHER STAGED OPERATION FOR CLIMATE CONTROL SYSTEM BASED ON LOWER STAGED THERMOSTAT CONDITIONING CALLS

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

BACKGROUND

A climate control system, such as a heating, air-conditioning, and ventilation (HVAC) system, may be used to condition the climate of an interior space. The interior space may be an interior space of a house, apartment, building, retail store, storage unit, office, refrigerator, freezer, vehicle, etc. Conditioning the interior space may include either cooling or heating the interior space by use of the climate control system.

BRIEF SUMMARY

Some embodiments disclosed herein are directed to a climate control system for conditioning an interior space. In some embodiments, the climate control system includes a compressor that is configured to circulate a refrigerant in a fluid circuit, the compressor configured to operate at X different compressor speeds, a heat exchanger positioned along the fluid circuit, and a blower that is configured to generate an airflow that is to contact the heat exchanger and then flow into the interior space. In addition, the climate control system includes a controller communicatively coupled to the compressor. The controller is configured to receive an analog cooling call from a thermostat positioned in the interior space, the analog conditioning call being one of Y different analog cooling calls of the thermostat, Y being less than X. In addition, the controller is configured to select a target discharge temperature for the airflow based on the analog cooling call, the target discharge temperature being a target for a discharge temperature of the airflow downstream from the heat exchanger and upstream from the interior space. Further, the controller is configured to adjust a speed of the compressor among the X different compressor speeds based on the target discharge temperature.

Some embodiments disclosed herein are directed to a method of controlling a climate control system to condition an interior space. In some embodiments, the method includes receiving an analog conditioning call from a thermostat. In addition, the method includes selecting a target discharge temperature for an airflow output by the climate control system to the interior space based on the analog conditioning call received from the thermostat. Further, the method includes adjusting a speed of a compressor of the climate control system among to a plurality of different compressor speeds based on the target discharge temperature.

Some embodiments disclosed herein are directed to an air conditioning system for cooling an interior space. In some embodiments, the air conditioning system includes a thermostat that is configured to output an analog low cooling stage call and an analog high cooling stage call based on a difference between a temperature of the interior space and a set point temperature, a compressor that is configured to operate at least three different compressor speeds to circulate a refrigerant through a fluid circuit of the air conditioning system, and an evaporator that is positioned along the fluid circuit. In addition, the air conditioning system includes a blower that is configured to generate an airflow that is to contact the evaporator and then flow into the interior space. Further, the air conditioning system includes a controller communicatively coupled to the temperature sensor, the thermostat, and the compressor. The controller is configured to adjust a speed of the compressor among the at least three different compressor speeds to reduce an error between the discharge temperature of the airflow detected by the temperature sensor and a first target discharge temperature in response to receipt of the analog low cooling stage call from the thermostat. In addition, the controller is configured to adjust the speed of the compressor among the at least three different compressor speeds to reduce an error between the discharge temperature of the airflow detected by the temperature sensor and a second target discharge temperature in response to receipt of the analog high cooling stage call from the thermostat, the second target discharge temperature being less than the first target discharge temperature.

Embodiments described herein comprise a combination of features and characteristics intended to address various shortcomings associated with certain prior devices, systems, and methods. The foregoing has outlined rather broadly the features and technical characteristics of the disclosed embodiments in order that the detailed description that follows may be better understood. The various characteristics and features described above, as well as others, will be readily apparent to those having ordinary skill in the art upon reading the following detailed description, and by referring to the accompanying drawings. It should be appreciated that this disclosure may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes as the disclosed embodiments. It should also be realized that such equivalent constructions do not depart from the spirit and scope of the principles disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

For a detailed description of various embodiments, reference will now be made to the accompanying drawings in which:

FIGS. 1 and 2 are a schematic diagrams of a climate control system for conditioning an interior space in different modes of operation according to some embodiments disclosed herein;

FIG. 3 is an example lookup table to selecting a target discharge temperature for airflow of the climate control system based on a conditioning call output by a thermostat according to some embodiments disclosed herein;

FIG. 4 is a flow chart of a routine that may be performed by a controller of an embodiment of a climate control system described herein to adjust a speed of a blower during operations according to some embodiments disclosed herein;

FIG. 5 is a flow chart of a method of operating a climate control system to operate a greater number of stages or levels based on a lowered staged conditioning call from a thermostat according to some embodiments disclosed herein; and

FIG. 6 is a schematic diagram of a climate control system for conditioning an interior space according to some embodiments disclosed herein.

DETAILED DESCRIPTION

As previously described, a climate control system may condition an interior space. For instance, the climate control system may exchange heat between an interior space and an ambient environment in order to cool or heat the interior space during operations. A climate control system may include or may communicate with a thermostat that is configured to monitor the temperature or other conditions in the interior space and output calls for operation of the climate control system based thereon.

Improvements in the design of climate control systems have yielded systems that are configured to operate at different levels or stages to deliver varying levels of heating or cooling capacity to an interior space. For instance, many climate control systems may deliver staged capacities (at a plurality of discrete heating or cooling stages) or variable capacities so as to more efficiently condition the interior space. However, staged or variable climate control systems are relatively complex and may therefore may not be configured to effectively communicate with earlier generation thermostats that are configured to communicate with a lower staged or even single staged system. As a result, an upgrade of an existing, lower-staged climate control system with an improved, higher staged system may require also upgrading and rewiring the thermostat within the interior space. However, replacing and rewiring a thermostat may add to the costs and scope of the system upgrade, and may cause post-installation construction steps (e.g., such as patching access holes made in the internal walls of the interior space to install the new and updating wiring for the new thermostat).

Accordingly, embodiments disclosed herein include systems and methods for operating a higher staged climate control system with a lower staged thermostat. In some embodiments, the systems and methods disclosed herein may use the lower staged analog conditioning call(s) output from the thermostat to set additional operating parameters useful for operating the other components of the climate control system at additional available stages during operations. Thus, through use of the embodiments disclosed herein, a higher staged climate control system may operate to more efficiently condition an indoor space via communication with a lower staged thermostat, which may reduce the costs and complexities of installing (e.g., such as upgrading) a higher staged climate control system.

Referring now to FIGS. 1 and 2, a climate control system 10 for conditioning an interior space 12 is shown according to some embodiments disclosed herein. The interior space 12 is shown to include the interior space of a house or dwelling 14; however, as previously described, the interior space 12 may comprise any other suitable interior space that may be conditioned by a climate control system (e.g., climate control system 10). For instance, the interior space 12 may comprise the interior space of a building, office, retail space, storage unit, refrigerator, freezer, etc.

The climate control system 10 may be configured to circulate a refrigerant through a fluid circuit (or refrigerant circuit) 58 to transfer heat between the interior space 12 and an ambient environment 5. The ambient environment 5 may comprise an environment that at least partially surrounds the interior space 12. For instance, in the embodiment illustrated in FIG. 1, the interior space 12 is an interior space of a house 14, and the ambient environment comprises the outdoor environment that surrounds the house 14.

The climate control system 10 may include a compressor 30, a first heat exchanger 32, a pair of expansion devices 36, 42, a second heat exchanger 44, and a reversing valve 28 that are interconnected by a plurality of refrigerant lines 56 to at least partially define the fluid circuit 58. The fluid circuit 58 may circulate any suitable refrigerant (or refrigerants) during operations. For instance, in some embodiments, the fluid circuit 58 may be circulate one or more refrigerants that may comprise hydrofluorocarbons (HFCs), chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), fluorocarbons (FCs), hydrocarbons (HCs), Ammonia (NH₃), carbon dioxide (CO2), or some combination thereof.

In the embodiment illustrated in FIGS. 1 and 2, the climate control system 10 may comprise a heat pump that may be operated to selectively cool or heat the interior space 12 via the fluid circuit 58 during operations. Thus, during a cooling mode operation of the climate control system 10 illustrated in FIG. 1, the climate control system 10 may generally transfer heat from the interior space 12 to the ambient environment 5 via the fluid circuit 58, and during a heating mode operation of the climate control system illustrated in FIG. 2, the climate control system 10 may generally transfer heat from the ambient environment 5 to the interior space 12 via the fluid circuit 58. Each of the cooling mode operation (FIG. 1) and heating mode operation (FIG. 2) will be described in more detail.

As shown in FIG. 1, during a cooling mode operation to cool the interior space 12, the compressor 30 compresses the refrigerant in a gaseous state and outputs the compressed refrigerant to the reversing valve 28, which may then route the compressed refrigerant to the first heat exchanger 32. In the cooling mode operation of FIG. 1, the first heat exchanger 32 is configured to facilitate heat transfer from the refrigerant to the ambient environment 5. Specifically, the refrigerant may flow through one or more coils 34 of the first heat exchanger 32, while a fan 38 generates an airflow 40 that is flowed over and around the one or more coils 34 to thereby draw heat away from the refrigerant flowing therein. The airflow 40 is then directed away from the first heat exchanger 32 and into the ambient environment 5. The transfer of heat from the refrigerant to the airflow 40 via the first heat exchanger 32 may cause the refrigerant to at least partially condense to a liquid, such that the first heat exchanger 32 may function as a “condenser” when operating in the cooling mode of FIG. 1.

The liquid (or substantially liquid) refrigerant is then directed through the first expansion device 36 and then the second expansion device 42. In the cooling mode operation of FIG. 1, the first expansion device 36 may be positioned or actuated as to not substantially restrict or meter the flow of refrigerant therethrough. However, the second expansion device 42 may be actuated or set so as to controllably constrict and expand the flow of refrigerant so as to reduce a temperature thereof. The first expansion device 36 and second expansion device 42 may comprise expansion valves, such as electronic expansion valves (EEVs) that are actuated by a controller (e.g., controller 80 described herein). Alternatively, the first expansion device 36 and the second expansion device 42 may comprise a thermostatic expansion valve (TXV) that is configured to adjust in position (that is, in opening position) in response to one or more pressures and/or temperatures of the refrigerant flowing in the fluid circuit 58 (or a portion thereof).

The expanded, cold refrigerant is then directed through the second heat exchanger 44 which is configured to transfer heat from an airflow 50 generated by a blower 48 to the refrigerant. Specifically, the refrigerant may flow through one or more coils 46 of the second heat exchanger 44, while the blower 48 generates the airflow 50 that is flowed over and around the one or more coils 46 to thereby draw heat away from the airflow 50 and into the refrigerant.

The cooled airflow 50 is then discharged from the second heat exchanger 44 to the interior space 12 so as to reduce a temperature (and relatively humidity) therein. The airflow 50 may be discharged from the second heat exchanger 44 to the interior space 12 via suitable ducting 52 (e.g., rigid ducts, flexible hoses, or any other suitable fluid conveyance system).

The transfer of heat from the airflow 50 to the refrigerant via the second heat exchanger 44 may cause the refrigerant to vaporize or at least partially vaporize to a gas, such that the second heat exchanger 44 may function as an “evaporator” when operating in the cooling mode of FIG. 1. The vaporized (or partially vaporized) refrigerant may progress from the second heat exchanger 44 back to the compressor 30 via the reversing valve 28 so as to restart the cycle described above.

Referring now to FIG. 2, during a heating mode of the climate control system 10 the flow direction of the refrigerant in the fluid circuit 58 is generally reversed from that described for the cooling mode operation (FIG. 1). Specifically, during a heating mode operation, the reversing valve 28 is actuated so as to route the compressed refrigerant emitted from the compressor 30 to the second heat exchanger 44 rather than the first heat exchanger 32. As a result, in the heating mode operation shown in FIG. 2, the second heat exchanger 44 is configured to transfer heat from the refrigerant to the interior space 12 via airflow 50 so as to condense the refrigerant. Thus, in the heating mode operation of FIG. 2, the second heat exchanger 44 functions as a “condenser” for the refrigerant. The condensed refrigerant is then directed through the second expansion device 42 and the first expansion device 36; however, in the heating mode operation of FIG. 2, the second expansion device 42 is positioned or actuated so as to not substantially restrict or meter the flow of refrigerant therethrough, and the first expansion device 36 is actuated so as to controllably constrict and expand the flow of refrigerant so as to reduce a temperature thereof.

The expanded, cold refrigerant is then directed through the first heat exchanger 32 which is configured to transfer heat form the airflow 40 to the refrigerant to thereby vaporize the refrigerant and cool the airflow 40. Thus, in the heating mode operation, the first heat exchanger 32 functions the “evaporator” for the refrigerant. Finally, the vaporized refrigerant is routed ack to the compressor 30 via the reversing valve 28 to restart the cycle described above.

Referring again to FIGS. 1 and 2, in some embodiments, the second heat exchanger 44, second expansion device 42, and blower 48 may be embodied as an at least partially integrated first unit 60. In addition, in some embodiments, the first heat exchanger 32, first expansion device 36, fan 38, reversing valve 28, and compressor 30 may be embodied as an at least partially integrated second unit 70. In some embodiments, the first unit 60 may be positioned in any suitable indoor space that may or may not be the same (or connected to) the interior space 12. For instance, the first unit 60 may be positioned in an attic, storage room, basement, building, enclosure, that is proximate to, connected to, or at least partially integrated (or inside of) the interior space 12. Likewise, the second unit 70 may be positioned in the ambient environment 5, which (as previously described) may be outdoors. Thus, in some embodiments, the first unit 60 may be referred to herein as an “indoor unit” and the second unit 70 may be referred to as an “outdoor unit.”

However, these example positions of the units 60, 70 are not intended to limit a particular location of either of the units 60, 70 in various embodiments. For example, in some embodiment, the first unit 60 and second unit 70 may be at least partially integrated with one another and co-located in single location. For instance, in some embodiments, the first unit 60 and the second unit 70 may be integrated with one another as a so-called “packaged unit” and located in the ambient environment 5. In some embodiments, the at least partially integrated units 60, 70 (e.g., as a packaged unit) may be positioned on a rooftop of the house 14, dwelling, building, etc. that defines the interior space 12. Thus, in these embodiments, the climate control system 10 may be referred to as a so-called “rooftop unit.”

A thermostat 20 may be positioned in the interior space 12 that is configured to initiate, cease, or direct at least some functions of the climate control system 10 during operations. For instance, the thermostat 20 may include or be coupled to a temperature sensor 24 that is configured to detect or measure the temperature (or value indicative thereof) within the interior space 12. The temperature sensor 24 may comprise any suitable temperature sensing device or array, such as, a thermocouple, thermistor, resistance temperature detectors, solid state temperature sensors (e.g., semiconductor temperature sensors), etc. In addition, as described in more detail herein, the thermostat 20 may include one or more additional sensors for measuring or detecting other climate conditions within the interior space 12, such for instance, the relative humidity.

The thermostat 20 may output calls to initiate operation of the climate control system 10 in either the cooling mode (FIG. 1) or heating mode (FIG. 2) based at least in part on an output signal from the temperature sensor 24 (that may be at least indicative of the temperature in the interior space 12). Specifically, in some embodiments, the thermostat 20 may output a call to initiate operation of the climate control system 10 in the cooling mode operation (FIG. 1) when the output signal from the temperature sensor 24 (that is received by the thermostat 20) indicates that the temperature within the interior space 12 has sufficiently risen above a corresponding set point temperature. The set point temperature may have been set by a user, such as an occupant of the interior space 12. Similarly, in some embodiments, the thermostat 20 may output a call to initiate operation of the climate control system in the heating mode operation (FIG. 2) when the output signal from the temperature sensor 24 (that is received by the thermostat 20) indicates that the temperature within the interior space 12 has sufficiently fallen below a corresponding set point temperature (which again may have been previously set by a user, such as an occupant of the interior space 12).

The call to initiate either cooling mode operation or heating mode operation may be received by one or more, such as a plurality of components or assemblies of the climate control system 10. For instance, the call to initiate a cooling mode or heating mode operation may be received by one or more controllers (e.g., controller 80 described in more detail below) of climate control system 10. Upon receipt (and in response thereto), the one or more controllers (or other components) may initiate operation in the desired mode (e.g., cooling or heating) to reduce an error between the current temperature in the interior space 12 (as detected by temperature sensor 24) and the corresponding set point temperature.

In addition, the call from the thermostat 20 may also indicate a stage or level of cooling mode or heating mode operation for the climate control system 10 to engage in. For instance, the thermostat 20 may be configured to at least partially control, initiate, direct, etc. operation of a climate control system in a plurality of stages or levels in order to provide different levels of cooling or heating capacity to the interior space 12. As a simple example, the thermostat 20 may be configured to operate a climate control system in a first or low stage of cooling or heating to deliver a first or low level of cooling or heating capacity to interior space, and in a second or high stage of cooling or heating to deliver a second or high level of cooling or heating capacity to interior space 12. The heating or cooling capacity may comprise a measure or indication of the rate of heat transfer (or change) in the interior space 12. Thus, a lower heating or cooling capacity may provide a relatively slower rate of heat transfer, and a higher heating or cooling capacity may provide a relatively faster rate of heat transfer with the interior space 12. In some embodiments, the thermostat 20 may output a call for either low stage or high stage cooling or heating from the climate control system 10 based at least in part on the difference between the current temperature in the interior space 12 (as detected by temperature sensor 24) and the corresponding set point temperature. Thus, if the difference or error between the current temperature and corresponding set point temperature rise above a threshold, the thermostat 20 may initiate the higher stage(s) of cooling or heating in order to more quickly reduce the difference or error. In some embodiments, the thermostat 20 may additionally (or alternatively) determine which cooling or heating stage to operate the climate control system 10 based at least in part on the temperature in the ambient environment 5 (e.g., such as an outdoor ambient temperature). For instance, the thermostat 20 may output a call for a higher stage of cooling when the temperature of the ambient environment 5 rises (e.g., above a threshold) during a cooling mode operation (FIG. 1), and may output a call for a higher stage of heating when the temperature of the ambient environment 5 falls (e.g., below a threshold) during a heating mode operation.

With respect to the cooling or heating mode operations for the climate control system 10 described above and shown in FIGS. 1 and 2, the different stages or levels of cooling or heating may be achieved via different flow rates of refrigerant in the fluid circuit 58. Specifically, as the flow rate of refrigerant increases in the fluid circuit 58, the rate of heat transfer in the heat exchangers 32, 44 may also increase, which may in turn increase the rate of heat transfer between the refrigerant the interior space 12 and ambient environment 5. Thus, a low cooling or heating stage operation of the climate control system 10 may correspond with a first or low operating speed of the compressor 30 (to provide a first or low flow rate of refrigerant in the fluid circuit 58) and a high cooling or heating stage operation of the climate control system 10 may correspond to a second or high operating speed of the compressor 30 (to provide a second or high flow rate of refrigerant in the fluid circuit 58). In some embodiments, the flow rates of the airflows 40, 50 may also be adjusted (e.g., via fan 38 and blower 48, respectively) in concert with the changes in the speed of the compressor 30. That is, the blower 48 and the fan 38 may be configured to operate at a plurality of different speeds to as to vary the speed or flow rate of the airflows 50 and 40, respectively.

As is described in more detail herein, in some embodiments the climate control system 10 may not comprise a heat pump and may utilize a supplemental heating assembly (e.g., supplemental heating unit 250 shown in FIG. 6) to heat the interior space 12. In these embodiments, the thermostat 20 may be configured to operate the supplemental heating assembly (e.g., electrically resistive heater, combustion furnace, etc.) at a plurality of different levels by adjusting one or more operating parameters thereof (e.g., electrical current supply, fuel flow rate, etc.).

The calls from the thermostat 20 to initiate or cease operation of the climate control system 10 or to operate the climate control system 10 at different levels or stages of heating or cooling may comprise analog electrical signals. Specifically, the thermostat 20 may include a plurality of electrical terminals 22 that may be electrically connected (e.g., via wires) to one or more other components (or controllers) of climate control system 10. The electrical terminals 22 may comprise an electrically conductive connector, pad, wire connector, junction, etc. that may be selectively energized by the thermostat 20. During operations, the thermostat 20 may selectively energize one or more of these electrical terminals 22, and this electrical current is then conducted (as a call) to the one or more other components of climate control system 10 that are connected thereto. Upon receipt of the analog electrical signal (which may comprise a 24 volt current in some embodiments) the one or more other components may then initiate, adjust, cease, etc. operation as appropriate. As used herein, an “analog call,” from the thermostat 20, such as an “analog cooling call,” “an analog heating call,” an “analog conditioning call” and the like may refer to an electrical signal that comprises a continuous electrical current at a set voltage (e.g., such as a constant 24 Volt signal) that is produced by energizing a corresponding electrical terminal (e.g., a corresponding one of the electrical terminals 22 on thermostat 20). Thus, the calls from the thermostat 20 may not include specific data or information and may comprise simple analog electrical signals.

As described in more detail below, the climate control system 10 (or at least a portion thereof) may be configured to operate at a greater number of stages or levels than the thermostat 20. For instance, the thermostat 20 may have originally been installed to communicate with an earlier or original climate control system (not shown) that was previously installed to condition the indoor space 12. The earlier climate control system (not shown) may have been configured to operate at the same number of stages or levels as the thermostat 20.

The climate control system 10 may comprise an upgraded or newer climate control system that is configured (at least in part) to operate at a higher number of stages than the thermostat 20 and earlier climate control system (not shown). For instance, one or more other components (e.g., such as one or more of compressor 30, fan 38, blower 48 etc.) of the climate control system 10 may be configured to operate at X number of stages during a cooling mode operation or a heating mode operation, while the thermostat 20 may be configured to output conditioning calls for X number of stages during a cooling moder operation or heating mode operation, in which X is greater than Y.

Specifically, the thermostat 20 may be configured to operate at a single stage (e.g., on-off), at two-stages (e.g., low and high), three stages (e.g., low, medium, high) in a cooling mode operation or a heating mode operation, and the one or more other components of the climate control system 10 may be configured to operate at two-stages (e.g., low and high), three stages, four stages, respectively, in a cooling mode operation or heating mode operation. In some embodiments, the thermostat 20 may be configured to operate at a finite number of stages (e.g., one stage, two stages, three stages, etc.) in a cooling mode or heating mode operation, and the one or more other components of the climate control system 10 may be variable in that they may operate at a plurality of stages/levels within a defined range (e.g., such as 0-100%, 20-100%, 30-90%, etc.) during either a cooling mode operation or heating mode operation. In each of these examples, components of the climate control system 10, such as the compressor 30, blower 48, fan 38, etc., may be configured to operate a higher number of stages than the number of stages that the thermostat 20 may output calls for, during either a cooling mode operation or heating mode operation.

Thus, the climate control system 10 may also include a controller 80 that is communicatively coupled (via any suitable wired and/or wireless connection(s)) to the thermostat 20 and one or more other components of the climate control system 10 (e.g., such as the compressor 30, the blower 48, etc. During operation, the controller 80 may be configured to receive one or more conditioning calls (e.g., for cooling or heating) from thermostat 20 and then output suitable signals, commands, instructions, etc. to the one or more other components of the climate control system 10 to direct operation thereof. Specifically, as described in more detail below, the controller 80 may be configured to covert or translate the fewer stage calls output from the thermostat 20 into suitable commands to operate the other components of the climate control system 10 at the greater number of stages (e.g., X as previously described) during either a cooling mode operation (FIG. 1) or a heating mode operation (FIG. 2).

The controller 80 may be (or may be incorporated within) a main or master controller for the climate control system 10, or the controller 80 may be a standalone controller 80 for translating or converting the analog conditioning calls of the thermostat 20 into suitable instructions for operating the one or more other components of the climate control system 10 at a greater number of stages. Regardless, the controller 80 may be described and referred to herein as being a part of the climate control system 10.

The controller 80 may comprise one or more computing devices, such as a computer, tablet, smartphone, server, circuit board, or other computing device(s) or system(s). Thus, controller 80 may include a processor 82 and a memory 84.

The processor 82 may include any suitable processing device or a collection of processing devices. In some embodiments, the processor 82 may include a microcontroller, central processing unit (CPU), graphics processing unit (GPU), timing controller (TCON), scaler unit, or some combination thereof. During operations, the processor 82 executes machine-readable instructions (such as machine-readable instructions 86) stored on memory 84, thereby causing the processor 82 to perform some or all of the actions attributed herein to the controller 80. In general, processor 82 fetches, decodes, and executes instructions (e.g., machine-readable instructions 86). In addition, processor 82 may also perform other actions, such as, making determinations, detecting conditions or values, etc., and communicating signals. If processor 82 assists another component in performing a function, then processor 82 may be said to cause the component to perform the function.

The memory 84 may be any suitable device or collection of devices for storing digital information including data and machine-readable instructions (such as machine- readable instructions 86). For instance, the memory 84 may include volatile storage (such as random-access memory (RAM)), non-volatile storage (e.g., flash storage, read-only memory (ROM), etc.), or combinations of both volatile and non-volatile storage. Data read or written by the processor 82 when executing machine-readable instructions 86 can also be stored on memory 84. Memory 84 may include “non-transitory machine-readable medium,” where the term “non-transitory” does not include or encompass transitory propagating signals.

The processor 82 may include one processing device or a plurality of processing devices that are distributed within (or communicatively coupled to) controller 80 or more broadly within climate control system 10. Likewise, the memory 84 may include one memory device or a plurality of memory devices that are distributed within (or communicatively coupled to) controller 80 or more broadly within climate control system 10. Thus, the controller 80 may comprise a plurality of individual “controllers” distributed throughout the climate control system 10 and that may be communicatively coupled to one another.

Referring still to FIGS. 1 and 2, during operations with climate control system 10, the thermostat 20 may output suitable analog conditioning calls to operate the climate control system 10 in a select cooling stage (FIG. 1) or heating stage (FIG. 2) based at least in part on the temperature detected by the temperature sensor 24 as previously described. The thermostat 20 may output the appropriate conditioning call via energization of a select one or more of the electrical terminals 22 as previously described.

For instance, in some embodiments, the thermostat 20 may be configured to output conditioning calls for two-stages (e.g., a first or low stage and a second or high stage) during a cooling mode operation and two stages during a heating mode operation. Specifically, the thermostat 20 may be configured to output an analog conditioning call associated with a low stage cooling operation (a “low stage cooling call”), an analog conditioning call associated with a high stage cooling operation (a “high stage cooling call”), an analog conditioning call associated with a low stage heating operation (a “low stage heating call”), and an analog conditioning call associated with a high stage heating operation (a “high stage heating call”). The low stage cooling call and high stage cooling call may be identified herein with the symbols Y1 and Y2, respectively, and the low stage heating call and high stage heating call may be identified with the symbols W1 and W2,respectively. Each of the cooling calls Y1, Y2, and heating calls W1, W2 may be associated with a select one of the terminals 22 on thermostat 20. So, during operations, the thermostat 20 may energize a first terminal 22 to output the low stage cooling call Y1, a second terminal 22 to output the high stage cooling call Y2, a third terminal 22 to output the low stage heating call W1, and a fourth terminal to output the high stage heating call W2. In some embodiments, the terminals 22 for the conditioning calls Y1, W1 and the terminals 22 for the conditioning calls Y2, W2 may be integrated or electrically coupled (or bridged) to one another.

During operations, the analog conditioning calls Y1, Y2, W1, W2 may be conducted from the thermostat 20 to the controller 80 via corresponding wires. Upon receipt of one of the analog conditioning calls Y1, Y2, W1, W2, the controller 80 may then operate (or direct operation) of one or more other components of the climate control system 10 at the greater number of stages (e.g., the X stages as previously described) via execution of the machine-readable instructions 86 by processor 82. Specifically, in some embodiments, the controller 80 may set an additional parameter (or parameters) for operating the climate control system 10 that are based or at least influenced by the analog conditioning call Y1, Y2, W1, W2 output from the thermostat 20. For instance, in some embodiments, the controller 80 may select a target for a discharge temperature of the airflow 50 and may then modulate the operation of one or more components of the climate control system 10 (e.g., compressor 30, fan 38, blower 48, expansion devices 36, 42, etc.) through the available stages or levels of operation in order to achieve or maintain the selected set point temperature during operation.

The climate control system 10 may include a temperature sensor 54 that is arranged to detect or determine a temperature of the airflow 50 after it is discharged from the first unit 60 toward the interior space 12. The temperature sensor 54 may be similar to the temperature sensor 24, and thus may include any of the suitable temperature sensing devices or arrays previously described for the temperature sensor 24.

The temperature sensor 54 may be positioned so as to be exposed to the airflow 50 upstream of the interior space 12 and downstream of the heat exchanger 44 (or other heat transfer device such as supplemental heating unit 250 as described in more detail below). In some embodiments, the temperature sensor 54 may be positioned in ducting 52 that directs the airflow 50 from the first unit 60 to the interior space 12; however, other positions (e.g., such as at an exit of the ducting 52 in the interior space 12, within the first unit 60, at an outlet of the heat exchanger 44 or other heat transfer device, etc.) are contemplated herein. The temperature sensor 54 may provide an output that is communicated (e.g., via wired or wireless connection) to the controller 80.

Each of the analog conditioning calls Y1, Y2, W1, W2 may be associated with a preselected target discharge temperature for the airflow 50. The preselected target temperatures may be selected at a factory or manufacturing site for the climate control system 10, or may be selected or set by a technician (e.g., such as during installation or maintenance of the climate control system 10). The preselected target discharge temperatures associated with the analog conditioning calls Y1, Y2, W1, W2 may be selected to provide a heating or cooling capacity sufficient to satisfy a cooling or heating demand of the interior space 12 at the corresponding temperature conditions that are configured to cause thermostat 20 to output the conditioning calls Y1, Y2, W1, W2. Thus, the specific target discharge temperatures applied by the controller 80 in response to receipt of one of analog conditioning calls Y1, Y2, W1, W2 from thermostat 20 may be different and unique for different embodiments or installations of the climate control system 10.

In some embodiments, the controller 80 may utilize a look up table, data base, or other suitable data storage system to select an appropriate target discharge temperature for the airflow 50 based at least in part on the received analog conditioning call Y1, Y2, W1, W2 from thermostat 20. For instance, FIG. 3 shows an example look-up table 90 that includes a first column 92 listing the different analog conditioning calls (e.g., Y1, Y2, W1, W2) that may be output from the thermostat 20, and a second column 94 listing the corresponding target discharge temperatures X1, X2, X3, X4 that may be selected for the discharge airflow 50 based on the received analog conditioning call Y1, Y2, W1, W2, respectively. The target temperatures X1, X2, X3, X4 are represented in degrees Fahrenheit (° F.); however, any suitable temperature scale may be used such as Celsius, Kelvin, etc.

In some embodiments, the controller 80 may select, determine, or calculate or otherwise determine the target discharge temperature for the airflow 50 based on the analog conditioning call (e.g., Y1, Y2, W1, W2) received from thermostat 20 and/or one or more additional parameters. For instance, the controller 80 may select, determine, or calculate a suitable target discharge temperature for the airflow based at least on the analog conditioning call received from the thermostat 20 and the outdoor ambient temperature (e.g., the temperature of the ambient environment 5). For instance, is some embodiments, the target discharge temperatures for the airflow 50 associated with one or more of the cooling stage calls (e.g., Y1, Y2) may be increase as the outdoor ambient temperature increases. Likewise, in some embodiments, the target discharge temperature for the airflow 50 associated with one or more of the heating stage calls (e.g., W1, W2) may be decreased as the outdoor ambient temperature decreases.

In some embodiments, an occupant of the interior space 12 (or other user) may select a target discharge temperature or operating mode for the climate control system 10 that corresponds with a target discharge temperature (or range or selection method). For instance, a user may select a dehumidification mode (e.g., via the thermostat 20, controller 80, or other user interface communicatively coupled to controller 80 and/or thermostat 20), and in response, the controller 80 may adjust the target discharge temperature for airflow 50 so that the climate control system 10 may more effectively or aggressively reduce a humidity (e.g., relative humidity) in the interior space 12. In the cooling mode operation, this may mean generally increasing the target discharge temperature relative to that normally corresponding to the particular cooling stage call (e.g., Y1, Y2) so as to allow the compressor 30 to run for a longer period of time to reduce humidity in the interior space 12.

As previously described, in some embodiments, the thermostat 20 is configured to output two cooling stage calls (e.g., Y1 and Y2) and potentially also two heating stage calls (e.g., W1 and W2). In some of these embodiments, the target discharge temperature for the airflow 50 for the low stage cooling call Y1 or the low stage heating call W1 may correspond with a cooling or heating capacity of the climate control system 10 that about 50% (or about half) of the cooling or heating capacity of the climate control system 10 that is necessary to hold the target discharge temperature for the airflow 50 for the high stage cooling call Y2 or the high stage heating call W2, respectively. Likewise, the high cooling stage call Y2 and the high stage heating call W1 may correspond with a maximum cooling capacity and maximum heating capacity, respectively, that may be provided by the climate control system 10.

In addition, in some embodiments, the target discharge temperature for the airflow 50 may be about 40° F. to about 60° F., such as about 50° F., in response and based on a high cooling stage call Y2 from the thermostat 20. Without being limited to this or any other theory, if the target discharge temperature is too low during a cooling mode operation, occupant comfort may be reduced and there is an increased risk of biological growth (e.g., mold) in the interior space 12. Conversely, a target discharge temperature that is too high may not remove sufficient heat from the interior space 12, and may therefore reduce the operating efficiency of the climate control system 10. Further, in some embodiments, the target discharge temperature for the airflow 50 may be about 90° F. to about 110° F., such as about 104° F., in response and based on a high heating stage call W2 from the thermostat 20. Again, without being limited to this or any other theory, a target discharge temperature that is too low during a heating mode operation may not add sufficient heat to the interior space 12, and may therefore reduce the operating efficiency of the climate control system. Conversely, if the target discharge temperature is too high during a heating mode operations, components of the climate control system 10 (e.g., blower 48, ducting 52, heat exchanger 44, etc.) may overheat.

Referring again to FIGS. 1 and 2, once the controller 80 selects the target temperature for the discharged airflow 50, the controller 80 may adjust operational parameter(s) of one or more of the components of climate control system 10 in order to achieve or maintain the target discharge temperature for airflow 50 via feedback from the temperature sensor 54. For instance, the controller 80 may adjust the speed of the compressor 30 to adjust the flow rate of refrigerant in the fluid circuit 58 (which affects the heat transfer rates at the heat exchangers 32, 44 as previously described). Without being limited to this or any other theory, the flow rate of the refrigerant in the fluid circuit 58 and thus the heat transfer rates achieved by the heat exchangers 32, 44 may directly affect the temperature of the discharged airflow 50 during operations. Generally speaking, during a cooling mode operation (FIG. 1), as the fluid flow rate of refrigerant in the fluid circuit 58 increases, the heat transfer rate from the airflow 50 to the refrigerant in the heat exchanger 44 also increases, so that the temperature of the discharged airflow 50 decreases. Conversely, during a heating mode operation (FIG. 2), as the fluid flow rate of refrigerant in the fluid circuit 58 increases, the heat transfer rate from the refrigerant to the airflow 50 in the heat exchanger 44 also increases, so that the temperature of the discharged airflow 50 increases.

The compressor 30 may be operatable at a number of speeds that are equal to the number of stages or levels (e.g., the X number of operational stages as previously described) for the climate control system 10 during operations. Alternatively, the compressor 30 may be operatable a plurality of speeds within a range-such as in the case that climate control system 10 is a variable (vs a staged) system. Thus, if the thermostat 20 is configured to output analog conditioning calls for two stages of cooling or heating, the compressor 30 may be operable at more than two different speeds (e.g., such as at least three, four, five, six, etc. speeds) to provide more than two levels of cooling or heating capacity to the interior space 12 during operations. The controller 80 may operate the compressor 30 at a plurality of different speeds by adjusting a speed of a motor (not specifically shown in the drawings) that is driving the compressor. In some embodiments, the compressor 30 may be driven by a variable frequency drive motor or another multi-speed electric motor that may be operated at a plurality of different speeds during operations.

During these operations, the controller 80 may freely adjust the speed of the compressor 30 along its entire operable range or among each of its available speeds so as to reduce an error between the current discharge temperature (via an output from the temperature sensor 54) of the airflow 50 and the target discharge temperature. In some embodiments, the controller 80 may utilize a feedback logic routine that uses this error in the discharge temperature of airflow 50 to adjust the speed of the compressor during operations. For instance, in some embodiments, the controller 80 may utilize a proportional, integral, and derivative (PID) loop to adjust the speed of the compressor 30 (e.g., by adjusting a speed of the motor driving the compressor 30 as previously described) based on the error in the discharge temperature of airflow 50. In some embodiments, the controller 80 may adjust the speed of the compressor 30 as a function of the error in the discharge temperature of airflow 50 (relative to the target discharge temperature). Generally speaking, in some embodiments, the controller 80 may generally increase the speed of the compressor 30 as the error in the discharge temperature of airflow 50 increases, and may generally decrease the speed of the compressor 30 as the error in the discharge temperature of the airflow decreases.

In a specific example, the thermostat 20 may output the high stage cooling call Y2 based at least in part on the difference between the set point temperature and the current temperature in the interior space 12 (via temperature sensor 24) as previously described. The controller 80 may receive the high stage cooling call Y2, and may in response select a target discharge temperature for the airflow 50, such as the target temperature X1° F. shown in table 90 in FIG. 3. Then, the controller 80 may set and/or adjust the operating speed of the compressor 30 (by adjusting an operating speed of the motor driving the compressor 30 as previously described) among all of its available operating speeds in order to minimize an error between the current discharge temperature of airflow 50 and the target temperature (e.g., X1° F.) as previously described. Thus, the operation of the compressor 30 may not be limited to two stages of operation that are communicated from the thermostat 20 and may be operated along its full operating range (or a desired subset thereof) or its available stages to more efficiently deliver the desired cooling or heating capacity to the interior space 12.

Basing the control of the speed of the compressor 30 on a target discharge temperature for the airflow 50 may provide some advantages for the climate control system 10. For instance, increases in the cooling or heating demand of the interior space 12 may be directly observed in deviations in the discharge temperature of the airflow 50 given that a temperature deviation in the interior space 12 will cause the incoming airflow 50 (which is largely or entirely derived from within the interior space 12) to also show the same or similar deviation. Thus, the speed of the compressor 30 may more directly respond to the changes in heating or cooling demands from the interior space 12 during operation by operating based on the discharge temperature of the airflow 50 as described. In addition, basing the control of the speed of the compressor 30 on a target discharge temperature for the airflow may help to prevent supplying an airflow that is too cold or warm in the event that one or more components of the climate control system 10 are oversized relative to the interior space 12. Also, control the compressor 30 based on the target temperature for the airflow 50 may help to maintain a desired temperature for the airflow 50 regardless of the temperature of the incoming air to the climate control system 10 (e.g., to form the airflow 50). Further, the target temperatures for the airflow 50 may allow for better balancing of the capacity of the climate control system across the available conditioning calls from the thermostat 20 (e.g., across the Y1, Y2 cooling stage calls or across the W1, W2 heating calls), which may provide for better control accuracy of the climate control system 10 across its full output capacity range.

The controller 80 may also adjust the operational state or speed of other components of the climate control system 10 based at least in part on the analog conditioning call output from thermostat 20. For instance, the operational speeds of the fan 38 and blower 48 may be adjusted by the controller 80 during operations. Specifically, the operational speeds of the fan 38 and/or blower 48 may be tied to the operational speed of the compressor 30, so that when a speed of the compressor 30 is adjusted, an operational speed of the fan 38 and/or blower 48 may also be adjusted accordingly. In some embodiments, the operational speeds of the fan 38 and/or blower 48 may be configured to achieve or maintain a minimal desired rate of heat transfer via the heat exchangers 32, 44, respectively. Thus, in some embodiments, as the speed of the compressor 30 increases, the speed of the fan 38 and/or blower 48 may also increase. In some embodiments, each speed of the compressor 30 may be related (e.g., by the controller 80) to a corresponding operating speed of the fan 38 and/or blower 48 to ensure a minimal level of operating efficiency and performance during operations. The speeds of the blower 48 may be referred to herein as “blower speeds,” and each blower speed may result in and correspond to an “airflow speed” of the airflow 50. Likewise, speeds of the fan 38 may be referred to herein as “fan speeds,” and each fan speed may result in and correspond to an “airflow speed” of the airflow 40.

Thus, the controller 80 may efficiently operate higher-staged equipment (e.g., compressor 30, blower 48, fan 38, etc.) of a climate control system 10 using a lowered- staged thermostat 20. As a result, components of the climate control system 10 may be upgraded to generally more efficient higher staged or fully variable designs without necessarily also necessitating a replacement and/or rewriting of the existing thermostat 20. Accordingly, the controller 80 may allow the higher staged components to serve as more of a “bolt-on” solution for improving an existing climate control system.

In some embodiments, the operation and/or speed of the blower 48 may also be adjusted independently of the current operating speed of the compressor 30 in at least some circumstances in order to enhance occupant comfort and/or operating efficiency of the climate control system 10. For instance, reference is now made to FIG. 4, which shows a flow chart of a method or routine 100 for adjusting the speed of the blower 48 that may be employed by the controller 80 during operation of climate control system 10 (FIGS. 1 and 2). The routine 100 shown in FIG. 4 may be representative of at least some of the machine-readable instruction 86 saved on memory 84 and executable by processor 82 during operations. In describing the features of routine 100 in FIG. 4, continuing reference will be made to the climate control system 10 shown in FIGS. 1 and 2.

Initially, at block 102, the controller 80 may generally operate the blower 48 at a minimum blower speed that is based on the current operating speed (or stage) of the compressor. The minimum blower speed for the blower 48 based on the current operating speed of the compressor 30 may be selected so as to provide a minimum heat transfer in the heat exchanger 44 at the corresponding compressor speed during operations. In some embodiments, the minimum heat transfer in the heat exchanger 44 may be configured to prevent overheating or freezing of the heat exchanger 44 and/or may be configured to maintain a minimal amount of occupant comfort or conditioning performance of the climate control system 10 during operations.

When the thermostat 20 outputs a call for a high (or a highest) stage operation (e.g., a high stage cooling call Y2 or a high stage heating call W2), the controller 80 may consider whether the high stage call (Y2, W2) has been closed (or active) for a period of time that is longer than a first threshold time at decision block 104. The first threshold time may be less than an hour in some embodiments, such as, instance, 10 minutes, 15 minutes, 20 minutes, etc. In some embodiments, the first threshold period of time may be selected to correspond with a period of time that one expects the climate control system 10 to be able to satisfy the cooling or heating demand in the interior space 12 (e.g., based on the difference between the set point temperature and current temperature of interior space 12 detected by temperature sensor 24) so as to either allow for shutting down of the climate control system 10 or at least removal (or opening) of the high stage conditioning demand Y2/W2 by the thermostat 20. Thus, if after the first threshold time, the thermostat 20 is still outputting a high stage conditioning call (Y2, W2) call, it may provide an indication that the climate control system 10 is not delivering sufficient cooling or heating capacity to maintain occupant comfort in the interior space 12.

Accordingly, if the determination at block 104 is “no,” such that the high stage conditioning call has not been closed for the first threshold time, the routine 100 may return to block 102 so as to continue to operate the blower 48 at the minimum blower speed based on the current compressor speed as previously described. Conversely, if the determination at block 104 is “yes,” such that the high stage conditioning call has been closed for the first threshold time, the routine 100 may proceed to block 106 to increase a speed of the blower 48 to a maximum blower speed. Increasing the speed of the blower 48 to the maximum blower speed may facilitate increase a flow rate of airflow 50 into the interior space 12. This increased flow rate of the airflow 50 may increase felt comfort by occupants in the interior space 12 (e.g., by increasing convective cooling or heating rates) and may help to increase a rate of air exchange in the interior space 12 so that a difference between the temperature in the interior space 12 and the set point temperature may be decreased more quickly or effectively.

After the speed of the blower 48 has been increased to the maximum blower speed, the routine 100 may determine, at decision block 108, whether the high stage conditioning call (Y2/W2) has stopped (or is “opened”) for a second threshold time. The second threshold time may be the same or different from the first threshold time. For instance, in some embodiments, the second threshold time may be less than an hour, such as, for instance, 10 minutes, 15 minutes, 20 minutes, etc. In some embodiments, operating the climate control system 10 to achieve the target temperature of the discharged airflow 50 and operating the blower 48 at a maximum speed may be expected to reduce a difference between a set point temperature and a current temperature in the indoor space 12. As a result, at some point, the thermostat 20 may cease (or open) the high stage conditioning call (Y2/W2). However, it may be desirable to continue to run the blower 48 at the maximum speed for some time after the high stage conditioning call (Y2/W2) has stopped in order to transfer additional thermal energy from/to the indoor space 12 and thereby help to prevent a rapid change in the interior space 12 following a reduction in the speed of the compressor 30. Thus, the second threshold time in block 108 may help to ensure that the blower operates for a minimal desired amount of time following ceasing (or opening) of the high stage conditioning call (Y2/W2).

If the determination at block 108 is “no,” such that the high stage conditioning call has not been opened for the second threshold time, the routine 100 may return to block 106 so as to continue to operate the blower 48 at the maximum blower speed. Conversely, if the determination at block 108 is “yes,” such that the high stage conditioning call has been opened for the second threshold time, the routine 100 may proceed to block 110 to operate the blower 48 at the minimum speed based on the current compressor speed as previously described. At block 110, if the speed of the compressor 30 has been reduced to zero as a result of opening both the high stage conditioning call (Y2/W2) and the low stage conditioning call (Y1/W1), then block 110 may include shutting down the blower 48.

Referring again to FIGS. 1 and 2, in some embodiments, the thermostat 20 may be configured to detect or determine a humidity, such as a relative humidity, of the indoor space 12 and activate an analog dehumidification call (or more simply “dehumidification call”) via a corresponding one of the terminals 22 when the humidity (or relative humidity) rises above a set point. The analog dehumidification call may be output from the thermostat 20 in addition to the conditioning calls previously described (e.g., Y1, Y2, W1, W2). In some embodiments, the controller 80 may be configured (e.g., via execution of machine-readable instruction 86 with processor 82) to receive the dehumidification call from the thermostat 20, and in response may adjust a speed of the compressor 30 and/or blower 48 to more aggressively or quickly reduce the relative humidity of the interior space 12. Specifically, when the controller 80 receives the dehumidification call from thermostat 20, the controller 80 may respond by increasing a speed of the compressor 30 and decreasing a speed of the blower 48. For instance, in some embodiments, the controller 80 may respond to a dehumidification call from the thermostat 20 by increasing a speed of the compressor 30 to a maximum speed and/or decreasing the speed of the blower 48 to a minimum speed. The maximum speed for the compressor 30 in response to a dehumidification call may be a maximum available or allowable speed for the compressor 30 or a predefined maximum speed that is below a maximum available or allowable speed. Likewise, in some embodiments, the minimum speed of the blower 48 may comprise a minimum available or allowable speed for the blower 48 or some predefined minimum speed of the blower 48 that is above a minimum available or allowable speed for the blower 48. Without being limited to this or any other theory, increasing the speed of the compressor 30 and decreasing the speed of blower 48 (and thus decreasing the speed of the airflow 50) may reduce a temperature of the coil 46 of second heat exchanger 44 so that additional water is condensed out of the airflow 50 to thereby more aggressively reduce a relative humidity of the interior space 12.

Thus, the controller 80 may deviate from the typical adjustments of the compressor 30 speed and blower 48 speed based on the target discharge temperature for airflow 50 as previously described, while the dehumidification call is output from the thermostat 20. However, once humidity, such as the relative humidity, of the interior space 12 has return to (or within an acceptable range of) the set point, the thermostat 20 may stop (or “open”) the dehumidification call (e.g., by de-energizing the corresponding terminal 22). In response, the controller 80 may detect the loss of the dehumidification call and return to adjusting the speeds of the compressor 30 and blower 48 based on the target discharge temperature of the airflow 50 as previously described.

Referring still to FIGS. 1 and 2, during operation with the climate control system 10, if the temperature sensor 54 should fail (or if the temperature sensor 54 is not installed), the controller 80 may (e.g., via execution of the machine-readable instructions 86) determine the loss or lack of the output signal from the temperature sensor 54 and adjust the operation of the climate control system 10 accordingly. For instance, if the temperature sensor 54 should fail (or not be installed), the controller 80 may revert to a staged control of the compressor 30, blower 48, and fan 38 that matches the staged conditioning calls output from the thermostat 20. More specifically, if the thermostat 20 is configured to output two stages of cooling calls (e.g., Y1 and Y2) or two stages of heating calls (e.g., W1 and W2) as previously described, the controller 80 may operate the compressor 30 and blower 48 at the same number of fixed stages (e.g., a first speed for a Y1 call, a second speed for a Y2 call, a third speed for a W1 call, and a fourth speed for a W2 call). As a result, when the temperature sensor 54 fails (or does not provide an output to controller 80), the controller 80 may not modulate or actively adjust the speeds of the compressor 30 and blower 48 during a particular conditioning call Y1, Y2, W1, W2 as previously described, and may simply apply a predetermined fixed speed for each particular conditioning call Y1, Y2, W1, W2. As previously described, during these operation, the controller 80 may adjust the speed of the compressor 30, and then the speed of the blower 48 and/or fan 38 may be adjusted or set based on the current operating speed of the compressor 30. In some embodiments, the predetermined fixed compressor speeds for some of the multiple different conditioning calls Y1, Y2, W1, W2 may be the same (e.g., the compressor speeds for Y1 and W1 or the compressor speeds for Y2 and W2). However, in some embodiments, the predetermined fixed speed of the compressor 30 may be unique and different for each of the conditioning calls Y1, Y2, W1, W2.

Referring now to FIG. 5, a method 150 of operating a climate control system according to some embodiments is shown. In describing the features of method 150, continuing reference will be made to the climate control system 10 shown in FIGS. 1 and 2. However, it should be appreciated that the method 150 may be practiced using embodiments of a climate control system that are different from the climate control system 10 of FIGS. 1 and 2 in at least some respect. Thus, reference to the climate control system 10 of FIGS. 1 and 2 when describing method 150 should not be interpreted as limiting all embodiments of method 150. Moreover, various embodiments of method 150 may include more or fewer features to those shown in FIG. 4.

Initially, method 150 includes a determining a temperature of an interior space by use of a thermostat at block 152. For instance, as previously described, the thermostat 20 may determine a current temperature in the interior space 12 via a temperature sensor 24. The thermostat 20 may then determine a difference between the current temperature and a set point temperature. The set point temperature may be selected by an occupant of the interior space or may be a default value. The difference between the current temperature and the set point temperature may be representative or indicative of the thermal load of the interior space 12.

In addition, method 150 also includes outputting a conditioning stage call from the thermostat based on the temperature of the interior space at block 154. For instance, as previously described, the thermostat 20 may determine a suitable conditioning call (e.g., such as Y1, Y2, W1, or W2) based at least in part on the difference between the current temperature of the interior space 12 and the set point temperature. In some specific examples, if the temperature difference between the set point temperature and the current temperature of interior space 12 is less than or equal to a threshold, the thermostat 20 may output a low (or lower) stage conditioning call (e.g., conditioning calls Y1, W1). Conversely, if the temperature different between the set point temperature and the current temperature of the interior space 12 is greater than the threshold, the thermostat 20 may output a high (or higher) stage conditioning call (e.g., conditioning calls Y2, W2).

As previously described, the thermostat 20 may be configured to output Y different conditioning calls in either cooling or heating mode. For instance, the thermostat 20 may be configured to output two cooling conditioning calls (e.g., low cooling call Y1, high cooling call Y2, low heating call W1, or high heating call W2), so that for either cooling mode or heating mode, Y may equal 2. However, other components of the climate control system 10 (e.g., such as compressor 30, blower 48, fan 38, etc.) may be configured to operate at X different stages or levels during either a cooling mode or heating mode operation, where X is greater than Y. For instance, the climate control system 10, and in particular the compressor 30 and blower 48 may be configured to operate at more than 2 different stages or levels during a cooling mode operation or a heating mode operation. Thus, the following features (e.g., blocks 156, 158, 160) of method 150 are configured to facilitate operation of the components of the climate control system across the greater number of stages or levels (X) based on the fewer number stage calls output from the thermostat so that the operational efficiency of the climate control system can be increased. Blocks 156, 158, 160 may be representative of at least some of the machine-readable instructions 86 stored on memory 84 and executed by processor 82 of controller 80 in embodiments of the climate control system 10 of FIGS. 1 and 2.

For instance, the method 150 includes receiving the conditioning stage call from the thermostat at block 156. For instance, as previously described for the climate control system 10 of FIGS. 1 and 2, the conditioning call from the thermostat 20 may be received by a controller 80 that is separate from the thermostat 20.

In addition, method 150 includes setting a target temperature for a discharge indoor airflow based on the conditioning stage call output from the thermostat at block 158. For instance, for the climate control system of FIGS. 1 and 2, the controller 80 may receive a conditioning call from the thermostat 20 and then, in response, may select a target temperature for the discharged airflow 50, the target temperature being at least partially based on the conditioning call received from the thermostat. As previously described, the target temperature may be determined using a look-up table or other suitable database, or may be calculated.

Further, the method 150 includes adjusting a compressor speed to achieve or maintain the target discharge airflow temperature at block 160, and adjusting the indoor airflow speed based on the compressor speed at block 162. For instance, as previously described for the climate control system 10 shown in FIGS. 1 and 2, after the discharge temperature for the airflow 50 is determined, the controller 80 may adjust the speed of the compressor 30 so as to minimize an error between the current temperature of the airflow 50 and the target. The controller 80 may use a feedback style control loop, such as a PID control loop, to reduce the error in the discharge temperature of the airflow 50 as previously described. The controller 80 may adjust the compressor 30 through the greater number of stages than the number of staged cooling or heating calls in order to minimize the error in the discharge temperature of airflow 50 during operations. Thus, the controller 80 may operate the compressor 30 at higher number of stages than the number of conditioning calls output from the thermostat 20 during a cooling mode or heating mode so as to more efficiently provide the desired cooling or heating capacity to the interior space 12.

In some embodiments, the controller 80 may apply a default compressor speed upon initial start up so as to initiate the flow of refrigerant through the fluid circuit 58, but may then adjust the speed of the compressor 30 based on the feedback from the temperature sensor 54 and the target temperature for the discharge of airflow 50 as previously described.

In addition, also as previously described, the speed of the blower 48 may be adjusted (e.g., by the controller 80) based on the current active speed of the compressor 30. For instance, the controller 80 may operate the blower 48 at a minimum pre-defined speed that corresponds to the current operating speed of the compressor 30. Thus, an adjustment to the speed of the compressor 30 may result in a corresponding change to the speed of the blower 48. Also, because the compressor speed 30 is at least partially based on the target temperature for the discharge of airflow 50, the blower sped 48 may to be said to be at least partially based on the target temperature of the discharge of airflow 50.

Referring now to FIG. 6, a climate control system 200 for conditioning an interior space 12 is shown according to some embodiments disclosed herein. The climate control system 200 may be similar to the climate control system 10 (FIGS. 1 and 2), and thus, the same reference numerals are used to indicate components of the climate control system 200 that are shared with the climate control system 10. In addition, the description below will primarily focus on the features and functions of the climate control system 200 that are different from the climate control system 10.

Specifically, the climate control system 200 may not be configured as a heat pump. As a result, the climate control system 200 may lack the reversing valve 28 (FIGS. 1 and 2), and may be configured to circulate refrigerant in a single direction along the fluid circuit 58. Specifically, the climate control system 200 may be configured to circulate refrigerant along the fluid circuit 58 so as to operate in a cooling mode that is similar to the cooling mode of climate control system 10 shown in FIG. 1.

In addition, the climate control system 200 may include a supplemental heating unit 250 that is separate from the heat exchangers 44, 32. The supplemental heating unit 250 may be configured to transfer heat to the airflow 50 during a heating mode operation of the climate control system 200. Thus, during a heating mode operation of the climate control system 200, the compressor 30 is not operating to circulate the refrigerant through the fluid circuit 58 and the supplemental heating unit 250. The supplemental heating unit 250 may be arranged adjacent to the heat exchanger 44 and exposed to the airflow 50. In some embodiments, the supplemental heating unit 250 may be positioned upstream or downstream of the second heat exchanger 44 relative to the direction of airflow 50. FIG. 5 shows the supplemental heating unit 250 downstream of the second heat exchanger 44 to illustrate one potential position thereof. Thus, the airflow 50 may be in contact with both the first heat exchanger 44 and the supplemental heating unit 250 before the airflow 50 progresses into the interior space 12 via the ducting 52.

In some embodiments, the supplemental heating unit 250 may comprise an electrically resistive heater including one or more resistive coils that emit heat when energized with electric current. The heat emitted from the one or more resistive coils may be adjusted by adjusting the electric current conducted thereto (e.g., by energizing different numbers/combinations of the one or more coils, by increasing the electrical current flowing through the one or more electrical coils, etc.). Alternatively, the supplemental heating unit 250 may comprise a furnace that is configured to combust a fuel (e.g., a hydrocarbon based fuel such as natural gas, or other suitable combustible fuel) and then transfer the heat of the combustion process to the airflow 50. In these embodiments, the heat transferred to the airflow 50 may generally be adjusted by adjusting a rate of fuel provided to and combusted by the supplemental heating unit. Thus, in various embodiments, the supplemental heating unit 250 may be operated in a plurality of different stages or levels by adjusting one or more operating parameters (e.g., electrical current supply, fuel supply, etc.) during operations.

The climate control system 200 may include the controller 80 that is configured to operate one or more components of the climate control system 200 (e.g., compressor 30, blower 48, etc.) through an X number of operating stages or levels that are greater than the Y number of cooling calls (e.g., Y1, Y2) that are output by the thermostat 20 as previously described. In addition, during a heating mode operation, the controller 80 may adjust a heating output to the airflow by the supplemental heating unit 25 (e.g., by adjusting one or more operating parameters of the supplemental heating unit 25 as previously described) based on a corresponding target temperature for the discharge airflow 50 during operations. In some embodiments, as is similarly described for the components arranged along fluid circuit 58 of climate control system 200 (e.g., compressor 30, blower 48), the supplemental heating unit 250 may be operable in a greater number of heating stages or levels than the number of heating calls (e.g., W1, W2) that may be output form the thermostat 20 during operations. Thus, upon receipt of a heating stage call (e.g., W1 or W2), the controller 80 may similarly select a target discharge temperature for the airflow 50 (see e.g., table 90 in FIG. 3) and then may adjust one or more operating parameters of the supplemental heating unit 250 in order to minimize an error in the discharge temperature of the airflow 50 relative to the target. Thus, as similarly described for the compressor, the controller 80 may operate the supplemental heating unit 250 among a greater number of stages of levels in response to a fewer number of heating calls from the thermostat 20 so that the climate control system 200 and more particularly the supplemental heating unit 250 may more efficiently satisfy the desired heating load for the interior space 12 during operations.

While the climate control system 10 shown in FIGS. 1 and 2 is configured as a heat pump as previously described, in some embodiments, the climate control system 10 of FIGS. 1 and 2 may be configured as a simply air-conditioning unit that is only configured to cool the interior space 12. In these embodiments, the reversing valve 28 may be omitted and the climate control system may be configured to operate in only the cooling mode of FIG. 1. In addition, the controller 80 may be configured to operate one or more components of the climate control system 10 (e.g., compressor 30, blower 48, fan 38, etc.) at a greater number of operating speeds (X number of operating speeds) in response to a fewer number of cooling calls (e.g., Y number of cooling calls, where Y is less than X) from the thermostat 20. Specifically, as previously described, the controller 80 may select a target discharge temperature for airflow 50 based on the cooling call (e.g., Y1, Y2, etc.) output from the thermostat 20 and then may adjust the speed of compressor 30 (as well as blower 48, fan 38) of the climate control system 10 through the greater number of available speeds to minimize the error in the discharge temperature of the airflow 50 relative to the target as previously described.

As explained above and reiterated below, the present disclosure includes, without limitation, the following example implementations.

Clause 1: A climate control system for conditioning an interior space, the climate control system comprising: a compressor that is configured to circulate a refrigerant in a fluid circuit, the compressor configured to operate at X different compressor speeds; a heat exchanger positioned along the fluid circuit; a blower that is configured to generate an airflow that is to contact the heat exchanger and then flow into the interior space; and a controller communicatively coupled to the compressor, the controller configured to: receive an analog cooling call from a thermostat positioned in the interior space, the analog conditioning call being one of Y different analog cooling calls of the thermostat, Y being less than X; select a target discharge temperature for the airflow based on the analog cooling call, the target discharge temperature being a target for a discharge temperature of the airflow downstream from the heat exchanger and upstream from the interior space; and adjust a speed of the compressor among the X different compressor speeds based on the target discharge temperature.

Clause 2: The climate control system of any of the clauses, wherein the controller is further configured to adjust a speed of the blower based on the speed of the compressor.

Clause 3: The climate control system of any of the clauses, wherein the controller is further configured to: determine that a temperature sensor for detecting the discharge temperature for the airflow has failed; and in response adjust the speed of the compressor to a preselected compressor speed that corresponds with the analog conditioning call received from the thermostat.

Clause 4: The climate control system of any of the clauses, wherein the controller is configured to adjust the speed of the compressor by increasing or decreasing the speed of the compressor to reduce an error between the discharge temperature and the target discharge temperature.

Clause 5: The climate control system of any of the clauses, wherein the controller is configured to select the speed of the compressor from the X different compressor speeds as a function of the error.

Clause 6: The climate control system of any of the clauses, wherein Y is two so that the thermostat is configured to output a low stage analog cooling call (Y1) and a high stage analog conditioning call (Y2), and wherein the controller is configured to: select a first target discharge temperature for the airflow in response to receipt of the low stage analog cooling call (Y1) from the thermostat; and select a second target discharge temperature for the airflow in response to receipt of the high stage analog cooling call (Y2) from the thermostat, the second target discharge temperature being different from the first target discharge temperature.

Clause 7: The climate control system of any of the clauses, wherein the controller is configured to increase the speed of the blower from a first blower speed to a second blower speed based on a determination that the high stage analog cooling call has been received from the thermostat for more than a threshold period of time.

Clause 8: The climate control system of any of the clauses, wherein the second blower speed comprises a maximum speed of the blower.

Clause 9: The climate control system of any of the clauses, wherein the controller is configured to maintain the speed of the blower at the second blower speed for a second threshold period of time after a loss of the high stage analog cooling call from the thermostat.

Clause 10: The climate control system of any of the clauses, wherein the controller is further configured to: receive an analog dehumidification call from the thermostat; and adjust the speed of the compressor to a maximum speed of the X different compressor speeds based on the analog dehumidification call; and operate the blower at a minimum blower speed in response to the analog dehumidification call.

Clause 11: A method of controlling a climate control system to condition an interior space, the method comprising: (a) receiving an analog conditioning call from a thermostat; (b) selecting a target discharge temperature for an airflow output by the climate control system to the interior space based on the analog conditioning call received from the thermostat; and (c) adjusting a speed of a compressor of the climate control system among to a plurality of different compressor speeds based on the target discharge temperature.

Clause 12: The method of any of the clauses, wherein the thermostat is configured to output a low stage cooling call and a high stage cooling call, wherein (a) comprises receiving the low stage cooling call from the thermostat; wherein (b) comprises selecting a first target discharge temperature for the airflow based on the received low stage cooling call; and wherein (c) comprises adjusting the speed of the compressor among the plurality of different compressor speeds to reduce an error between the target discharge temperature and a current discharge temperature for the airflow.

Clause 13: The method of any of the clauses, further comprising: (d) receiving the high stage cooling call from the thermostat; (e) selecting a second target discharge temperature for the airflow based on the high stage conditioning call, the second target discharge temperature being different form the first target discharge temperature; and (f) adjusting the speed of the compressor among the plurality of different compressor speeds based on the second target discharge temperature.

Clause 14: The method of any of the clauses, wherein the method further comprises: (g) determining that the high stage cooling call has been received from the thermostat for more than a first threshold period of time; and (h) increasing the speed of the airflow from a first airflow speed to a second airflow speed in response to the determination in (g).

Clause 15: The method of any of the clauses, further comprising: (i) maintaining the speed of the airflow at the second airflow speed for a second threshold period of time after loss of the high stage cooling call from the thermostat.

Clause 16: The method of any of the clauses, further comprising: (j) receiving an analog dehumidification call from the thermostat; (k) adjusting the speed of the compressor to a maximum speed of the plurality of different compressor speeds based on the analog dehumidification call; and (I) operating a blower of the climate control system at a minimum blower speed based on the analog dehumidification call.

Clause 17: An air conditioning system for cooling an interior space, the air conditioning system comprising: a thermostat that is configured to output an analog low cooling stage call and an analog high cooling stage call based on a difference between a temperature of the interior space and a set point temperature; a compressor that is configured to operate at least three different compressor speeds to circulate a refrigerant through a fluid circuit of the air conditioning system; an evaporator that is positioned along the fluid circuit; a blower that is configured to generate an airflow that is to contact the evaporator and then flow into the interior space; a temperature sensor configured to detect a discharge temperature of the airflow downstream of the evaporator and upstream of the interior space; a controller communicatively coupled to the temperature sensor, the thermostat, and the compressor, the controller configured to: adjust a speed of the compressor among the at least three different compressor speeds to reduce an error between the discharge temperature of the airflow detected by the temperature sensor and a first target discharge temperature in response to receipt of the analog low cooling stage call from the thermostat; and adjust the speed of the compressor among the at least three different compressor speeds to reduce an error between the discharge temperature of the airflow detected by the temperature sensor and a second target discharge temperature in response to receipt of the analog high cooling stage call from the thermostat, the second target discharge temperature being less than the first target discharge temperature.

Clause 18: The air conditioning system of any of the clauses, wherein the blower is configured to operate at a plurality of different blower speeds, and wherein the controller is further configured to: adjust a speed of the blower among the plurality of different blower speeds based on a speed of the compressor.

Clause 19: The air conditioning system of any of the clauses, wherein the controller is configured to increase the speed of the blower to a maximum speed of the plurality of different blower speeds in response to a determination that the analog high cooling stage call has been output from the thermostat for more than a threshold period of time.

Clause 20: The air conditioning system of any of the clauses, wherein the controller is configured to maintain the speed of the blower at the maximum speed for a second threshold period of time following loss of the analog high cooling stage call.

The embodiments disclosed herein include systems and methods for operating a higher staged climate control system with a lower staged thermostat. In some embodiments, the systems and methods disclosed herein may use the lower staged analog conditioning call(s) output from the thermostat to set additional operating parameters useful for operating the other components of the climate control system at additional available stages during operations. Thus, through use of the embodiments disclosed herein, a higher staged climate control system may operate to more efficiently condition an indoor space via communication with a lower staged thermostat, which may reduce the costs and complexities of installing (e.g., such as upgrading) a higher staged climate control system.

The preceding discussion is directed to various exemplary embodiments. However, one of ordinary skill in the art will understand that the examples disclosed herein have broad application, and that the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to suggest that the scope of the disclosure, including the claims, is limited to that embodiment.

The drawing figures are not necessarily to scale. Certain features and components herein may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in interest of clarity and conciseness.

In the discussion herein and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .” Also, the term “couple” or “couples” is intended to mean either an indirect or direct connection. Thus, if a first device couples to a second device, that connection may be through a direct connection of the two devices, or through an indirect connection that is established via other devices, components, nodes, and connections. In addition, as used herein, the terms “axial” and “axially” generally mean along or parallel to a given axis (e.g., central axis of a body or a port), while the terms “radial” and “radially” generally mean perpendicular to the given axis. For instance, an axial distance refers to a distance measured along or parallel to the axis, and a radial distance means a distance measured perpendicular to the axis. Further, when used herein (including in the claims), the words “about,” “generally,” “substantially,” “approximately,” and the like, when used in reference to a stated value mean within a range of plus or minus 10% of the stated value.

While exemplary embodiments have been shown and described, modifications thereof can be made by one skilled in the art without departing from the scope or teachings herein. The embodiments described herein are exemplary only and are not limiting. Many variations and modifications of the systems, apparatus, and processes described herein are possible and are within the scope of the disclosure. Accordingly, the scope of protection is not limited to the embodiments described herein, but is only limited by the claims that follow, the scope of which shall include all equivalents of the subject matter of the claims. Unless expressly stated otherwise, the steps in a method claim may be performed in any order. The recitation of identifiers such as (a), (b), (c) or (1), (2), (3) before steps in a method claim are not intended to and do not specify a particular order to the steps, but rather are used to simplify subsequent reference to such steps.