Method and Apparatus For Reducing Heat Losses In Reversible Vapor Compression System

Abstract

A vapor compression system includes an indoor heat exchanger, an outdoor heat exchanger, a compressor, a first valve, and a second valve. The compressor has an inlet connected to a suction flow and an exit connected to a discharge flow. The first valve is movable to connect the discharge flow to one of the indoor and outdoor heat exchangers. The second valve is movable to connect the suction flow to one of the indoor and outdoor heat exchangers.

Description

FIELD

The field of the disclosure relates generally to heating, ventilation, and air conditioning (HVAC) systems, and more particularly, to reversible vapor compression systems.

BACKGROUND

The vapor compression cycle is used to regulate the temperature and humidity of an interior space. In some applications, vapor compression systems are built to be reversible, such that the same system is operable to heat or cool an interior space as needed. Many reversible systems switch between heating and cooling modes using a four-way reversing valve to reverse the direction of flow through the system. The four-way reversing valve receives a discharge flow of high pressure, high temperature fluid from the compressor outlet. The valve is typically configured to direct the discharge flow to either an indoor or outdoor heat exchanger to release heat into its surroundings, either to heat the interior space or to reject waste heat into an outdoor space. The four-way reversing valve also receives fluid from the outlet of the other heat exchanger and directs it to the compressor inlet as a suction flow.

The suction and discharge flows are typically at very different temperatures, and the proximity of the two flow paths can enable heat transfer between them, thereby reducing the capacity of the system to meet the heating or cooling load for which it is designed. While heat transfer losses remain negligible in many common heat pump applications, the development of cold climate heat pumps has revealed that reversing valves become a significant source of heat loss at temperatures below freezing. Thus, there is a need for a reversible vapor compression system that prevents or reduces heat transfer between the compressor suction and discharge flows.

This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.

SUMMARY

One aspect is directed to a vapor compression system including an indoor heat exchanger, an outdoor heat exchanger, a compressor, a first valve, and a second valve. The compressor has an inlet fluidly connected to a suction flow and an exit fluidly connected to a discharge flow. The first valve is selectively positionable to fluidly connect the discharge flow to one of the indoor and outdoor heat exchangers. The second valve is selectively positionable to fluidly connect the suction flow to one of the indoor and outdoor heat exchangers.

Another aspect is directed to a reversing valve including a valve housing defining a valve channel along a length thereof, a discharge inlet assembly, a reversing assembly, and an actuator assembly. The discharge inlet assembly includes first and second discharge ports extending from a surface of the valve housing. The reversing assembly includes first and second reversing ports extending from the surface of the valve housing and a suction port extending from the surface of the valve housing between the first and second reversing ports. The actuator assembly is slidably disposed within the valve channel and selectively positionable between a first position, in which the first discharge port is fluidly connected to the first reversing port, and a second position, in which the second discharge port is fluidly connected to the second reversing port.

Still another aspect is directed to a reversing valve including a first reversing port, a second reversing port, a discharge port, and a suction port. The discharge port provides a discharge flow to one of the first and second reversing ports, and the suction port receives a suction flow from one of the first and second reversing ports. The reversing valve further includes means for reducing heat transfer to and from the discharge flow and/or the suction flow.

Various refinements exist of the features noted in relation to the above-mentioned aspects of the present disclosure. Additional features may also be incorporated in the above-mentioned aspects of the present disclosure as well. These refinements and additional features may exist individually or in any combination. For instance, various features discussed below in relation to any of the illustrated embodiments of the present disclosure may be incorporated into any of the above-described aspects of the present disclosure, alone or in any combination.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a first example vapor compression system in a cooling mode.

FIG. 2 is a schematic diagram of the first example vapor compression system shown in FIG. 1 in a heating mode.

FIG. 3 is a perspective view of a first example reversing valve in a cooling mode.

FIG. 4 is a perspective view of the first example reversing valve shown in FIG. 3 in a heating mode.

FIG. 5 is an enlarged view of a secondary actuation assembly of the first example reversing valve shown in FIGS. 3 and 4 in a cooling mode.

FIG. 6 is an enlarged view of the secondary actuation assembly of the first example reversing valve shown in FIGS. 3 and 4 in a heating mode.

FIG. 7 is a perspective view of a second example reversing valve.

FIG. 8 is a cross-sectional perspective view of the second example reversing valve shown in FIG. 7.

FIG. 9a is a cross-sectional side view of the second example reversing valve shown in FIG. 7 in a cooling mode.

FIG. 9b is a side schematic view of the second example reversing valve shown in FIG. 7 in a cooling mode.

FIG. 10a is a cross-sectional side view of the second example reversing valve shown in FIG. 7 in a heating mode.

FIG. 10b is a side schematic view of the second example reversing valve shown in FIG. 7 in a heating mode.

FIG. 11 is a schematic diagram of a second example vapor compression system including the second example reversing valve shown in FIG. 7 in a cooling mode.

FIG. 12 is a schematic diagram of the second example vapor compression shown in FIG. 11, configured in a heating mode.

FIG. 13 is a schematic diagram of a third example vapor compression system, configured in a cooling mode.

FIG. 14 is a schematic diagram of the third example vapor compression system shown in FIG. 13, configured in a heating mode.

FIG. 15 is a schematic diagram of a fourth example vapor compression system, configured in a cooling mode.

FIG. 16 is a schematic diagram of the fourth example vapor compression system shown in FIG. 15, configured in a heating mode.

FIG. 17 is a schematic diagram of a fifth example vapor compression system, configured in a cooling mode.

FIG. 18 is a schematic diagram of the fifth example vapor compression system shown in FIG. 17, configured in a heating mode.

FIG. 19 is a schematic diagram of a sixth example vapor compression system, configured in a cooling mode.

FIG. 20 is a schematic diagram of the sixth example vapor compression system shown in FIG. 19, configured in a heating mode.

FIG. 21 is a schematic diagram of a seventh example vapor compression system, configured in a cooling mode.

FIG. 22 is a schematic diagram of the seventh example vapor compression system shown in FIG. 21, configured in a heating mode.

FIG. 23 is a schematic diagram of an eighth example vapor compression system, configured in a cooling mode.

FIG. 24 is a schematic diagram of the eighth example vapor compression system shown in FIG. 23, configured in a heating mode.

FIG. 25 is a block diagram of a control system for the vapor compression systems shown in previous figures.

Corresponding reference characters indicate corresponding parts throughout the drawings.

DETAILED DESCRIPTION

For conciseness, examples will be described with respect to a reversible vapor compression system operable to heat or cool an interior space. However, other example methods and systems may be used for regulating the temperature of an enclosed space. A reversible vapor compression system can minimize heat losses by (1) modifying the design of the reversing valve to spatially and/or thermally isolate the suction and discharge flows within the valve, or by (2) modifying the configuration of the system as a whole to separate the suction and discharge flows into different valves.

FIGS. 1 and 2 are schematic diagrams of a first example vapor compression system 100 for cooling or heating an interior space 60 surrounded by an exterior space 80. The system 100 includes a single, reversible, closed refrigerant loop that includes a compressor 160, a first expansion device 130, a second expansion device 135, a reversing valve 300, an indoor heat exchanger 140, and an outdoor heat exchanger 120. In other embodiments of the present disclosure (not shown), the first system 100 may include multiple refrigerant loops to accommodate multiple compressors, or may operate in parallel with another system, such as a humidity control system. The configuration of the reversing valve 300 determines the direction of flow through the system, and thus whether the system is configured to cool or heat the interior space 60. The reversing valve 300 will be discussed in greater detail below with respect to FIGS. 3 and 4.

FIG. 1 illustrates the system 100 configured to operate in a cooling mode. Refrigerant enters the compressor 160 at a compressor inlet 110 as a low-pressure, low-temperature gas (i.e. a suction flow). The compressor 160 increases the pressure of the refrigerant, which exits the compressor 160 at the compressor exit 115 as a high-pressure, high-temperature gas (i.e. a discharge flow). The compressor 160 may be driven by a first VFD 162 or any other suitable motor.

The discharge flow passes through a first discharge path 301 of the reversing valve 300, which directs the refrigerant to the outdoor heat exchanger 120. The outdoor heat exchanger 120 functions as a condenser, removing heat Q_out from the refrigerant and releasing it into the exterior space 80 to convert the refrigerant gas into a high-pressure, high-temperature liquid. A first fan 190 produces a first airflow 194 from the outdoor heat exchanger 120 toward the exterior space 80, thereby exhausting warm air toward the exterior space 80. The first fan 190 may be driven by a second VFD 192 or any other suitable motor.

Downstream of the outdoor heat exchanger 120, the refrigerant bypasses the second expansion device 135 and flows through the first expansion device 130, which reduces the pressure of the refrigerant. In some embodiments, the pressure may be reduced until the liquid refrigerant's current temperature becomes the boiling point temperature at that pressure, and the refrigerant becomes a two-phase mixture as some of the liquid refrigerant boils and turns into a gas. The first expansion device 130 may be a fixed orifice, a thermal expansion valve, an electronic expansion valve, or another type of expansion device that allows the system 100 to function as described.

The first expansion device 130 is fluidly connected to the indoor heat exchanger 140, which receives low-pressure, low-temperature liquid refrigerant or a two-phase mixture of liquid and gaseous refrigerant at its inlet. The indoor heat exchanger 140 functions as an evaporator, with the refrigerant absorbing heat Q_in from the interior space 60 to change the phase of the refrigerant from liquid to gas. A second fan 150 produces a second airflow 154 across the indoor heat exchanger 140 toward the interior space 60, thereby cooling the interior space 60. The second fan 150 may be driven by a third variable frequency drive (VFD) 152 or by any other suitable motor. The gaseous refrigerant flow then passes through a first suction path 302 of the reversing valve 300 and is returned to the compressor inlet 110 as a suction flow.

FIG. 2 illustrates the first system 100 configured to operate in a heating mode. Similarly to the cooling mode, refrigerant enters the compressor 160 at the compressor inlet 110 as a low-pressure, low-temperature gas (i.e. a suction flow). The compressor 100 increases the pressure of the refrigerant, which exits the compressor 100 at the compressor exit 115 as a high-pressure, high-temperature gas (i.e. a discharge flow). The discharge flow passes through a second discharge path 303 of the reversing valve 300, which directs the refrigerant to the indoor heat exchanger 140. The indoor heat exchanger 140 functions as a condenser, removing heat Q_out from the refrigerant to convert the refrigerant gas into a high-pressure, high-temperature liquid. The second fan 150 produces the second airflow 154 across the indoor heat exchanger 140 toward the interior space 60, thereby releasing heat Q_out into the interior space 60.

Downstream of the indoor heat exchanger 140, the refrigerant bypasses the first expansion device 130 and flows through the second expansion device 135, which reduces the pressure of the refrigerant. The pressure may be reduced until the liquid refrigerant's current temperature becomes the boiling point temperature at that pressure, and the refrigerant becomes a two-phase mixture as some of the liquid refrigerant boils and turns into a gas. The second expansion device 135 may be a fixed orifice, a thermal expansion valve, an electronic expansion valve, or any type of expansion device that allows the system 100 to function as described.

The second expansion device 135 is fluidly connected to the outdoor heat exchanger 120, which receives low-pressure, low-temperature liquid refrigerant or a two-phase mixture of liquid and gaseous refrigerant at its inlet. The outdoor heat exchanger 120 functions as an evaporator, with the refrigerant absorbing heat Q_in from the exterior space 80 and changing phase from a liquid to a gas. The first fan 190 produces the first airflow 194 from the outdoor heat exchanger 120 toward the exterior space 80. The gaseous refrigerant flow then passes through a second suction path 304 of the reversing valve 300 and is returned to the compressor inlet 110 as a suction flow.

A first example reversing valve 300 is shown in FIGS. 3 and 4. The first example reversing valve 300 includes a valve housing 310 extending in a longitudinal direction from a first end 306 to a second end 307. The valve housing 310 defines a valve channel 312 extending along a length thereof. The reversing valve 300 also includes a discharge port 320, a suction port 330, and first and second reversing ports 340, 350. Each port 320-350 extends from a first end (not labeled) connected to a surface 314 of the valve housing 310 to a second, free end. Each port 320-350 also defines a channel (not labeled) along a length thereof, and an opening (not labeled) in the valve housing 310 at the first end of each port 320-350.

The discharge port 320 is disposed on a discharge side 316 of the valve housing 310, and the suction port 330 and first and second reversing ports 340, 350 are disposed on a suction side 318 of the valve housing that opposes the discharge side 316. The suction port 330 is positioned between the first and second reversing ports 340, 350 and is substantially aligned with the discharge port 320. The ports 320-350 may alternatively have any suitable configuration relative to the valve housing 310 that allows the reversing valve 300 to function as described.

While the valve housing 310 and ports 320-350 are illustrated as having a substantially circular cross-section, the valve housing 310 and ports 320-350 may have any suitable cross-sectional shape, for example and without limitation, square, elliptical, or polygonal. Similarly, the valve channel 312 and the channel defined by each port 320-350 may have any suitable cross-section, for example and without limitation, circular, square, elliptical, or polygonal, regardless of the cross-sectional shape of the valve housing 310 and port 320-350. While the ports 320-350 illustrated in FIGS. 3 and 4 all have substantially the same cross-sectional shape and area, other embodiments of the reversing valve may include ports with different cross-sectional shapes and areas. Furthermore, while each of the ports 320-350 illustrated in FIGS. 3 and 4 has a cross-sectional shape and area that is substantially the same along its length, other embodiments of the reversing valve 300 may include ports with cross-sections that vary in size or shape along the length of the port.

The reversing valve 300 also includes an actuator assembly 360 disposed within the valve channel 315 and slidable in the longitudinal direction x between the first and second ends 306, 307 of the valve housing 310. The actuator assembly 360 includes an actuator seat 362 and a slider 370 defining a slider cavity 372 therein. The actuator seat 362 defines a first discharge channel 364, a second discharge channel 366, and a slider opening (not labeled) through which a portion of the slider 370 is disposed. The actuator assembly 360 includes a first endcap 363 disposed on a first end thereof and a second endcap 365 disposed on a second end thereof, with both endcaps 363, 365 oriented substantially perpendicular to the actuator seat 362. The slider 370 also defines a first slider opening 374 and a second slider opening 376 therein.

During operation, the actuator assembly 360 is selectively positionable in a first position or a second position. In the first position (shown in FIG. 3), the actuator assembly 360 is positioned such that the first endcap 363 is adjacent and in contact with the first end 306 of the valve housing 310. The slider 370 is situated above the first reversing port 340 and the suction port 330 such that the first slider opening 374 is aligned with the first reversing port 340 and the second slider opening 376 is aligned with the suction port 330. The slider cavity 372 thus fluidly connects the first reversing port 340 to the suction port 330 when the actuator assembly is in the first position.

The discharge port 320 is fluidly connected to the second reversing port 350 through the second discharge channel 366 of the actuator seat 362. When the first example reversing valve 300 is installed in the vapor compression system 100 as shown in FIG. 1, such that the system 100 is configured to operate in cooling mode, the fluid path formed by the first reversing port 340, slider cavity 372, and suction port 330 forms the first suction path 302. The fluid path formed by the discharge port 320, the second discharge channel 366, and the second reversing port 350 forms the first discharge path 301. Thus, in the first position of the actuator assembly 360, the discharge port 320 provides the discharge flow to the second reversing port 350, and the suction port 330 receives the suction flow from the first reversing port 340.

In the second position, shown in FIG. 4, the actuator assembly 360 is positioned such that the second endcap 365 is adjacent and in contact with the second end 307 of the valve housing 310. The slider 370 is situated above the suction port 330 and the second reversing port 350 such that the first slider opening 374 is aligned with the suction port 330 and the second slider opening 376 is aligned with the second reversing port 350. The slider cavity 372 thus fluidly connects the suction port 330 to the second reversing port 350 when the actuator assembly 360 is in the second position.

Similarly, the discharge port 320 is fluidly connected to the first reversing port 340 through the first discharge channel 364 of the actuator seat 362. When the first example reversing valve 300 is installed in the vapor compression system 100 as shown in FIG. 2, such that the system 100 is configured in heating mode, the fluid path formed by the suction port 330, slider cavity 372, and second reversing port 350 forms the second suction path 304. The fluid path formed by the discharge port, the first discharge channel 364, and the first reversing port 340 forms the second discharge path 303. Thus, in the second position of the actuator assembly 360, the discharge port 320 provides the discharge flow to the first reversing port 340, and the suction port 330 receives the suction flow from the second reversing port 350.

With additional reference to FIGS. 5 and 6, the reversing valve 300 includes a secondary actuation assembly 380 operable to selectively position the actuator assembly 360 in the first or second positions described above. In the illustrated embodiment, the secondary actuation assembly 380 uses fluid pressure from the discharge and suction flows to generate a pressure differential across the actuator assembly 360 that pushes it towards the first end 306 of the valve housing 310 in the first position, or the second end 307 of the valve housing 310 in the second position. In other embodiments, the secondary actuation assembly 380 may use any other suitable mechanism for controlling the position of the actuator assembly 360.

The secondary actuation assembly 380 includes a secondary actuation housing 381 enclosing a solenoid 382 and a pilot valve 386. The solenoid 382 includes an electromagnetic coil (not shown) electrically connected to a power source (not shown). The pilot valve 386 includes a piston 388 slidable along a length of the secondary actuation housing 381 and mechanically connected to the solenoid 382 by a spring 384. The piston 388 also includes a piston slider 391 defining a piston slider cavity 393 therein.

Similar to the first example reversing valve 300 itself, and with reference to FIGS. 5 and 6, the pilot valve 386 also includes a discharge duct 325, a suction duct 335, a first reversing duct 345, and a second reversing duct 355, each extending from the secondary actuation housing 381. The discharge duct 325 is fluidly connected to the discharge port 320 and extends to the secondary actuation housing 381 therefrom. The suction duct 335 is fluidly connected to the suction port 330 and extends to the secondary actuation housing 381 therefrom. The first reversing duct 345 is fluidly connected to the valve channel 312 at the first end 306 of the valve housing 310 and extends to the secondary actuation housing 381 therefrom. The second reversing duct 355 is fluidly connected to the valve channel 312 at the second end 307 of the valve housing and extends to the secondary actuation housing 381 therefrom.

When the electromagnetic coil of the solenoid 382 is not energized, the spring 384 remains unloaded, and the piston 388 is positioned in a first piston position (shown in FIG. 5), in which an end 387 of the piston 388 is separated from an end 389 of the secondary actuation housing 381. In the first piston position, the piston slider cavity 393 fluidly connects the first reversing duct 345 to the suction duct 335, and the discharge duct 325 is fluidly connected to the second reversing duct 355 through the channel formed by the secondary actuation housing 381. Thus, a portion of the discharge flow in the discharge port 320 is routed through the discharge duct 325 and the second reversing duct 355 to the valve channel 312 proximate the second end 307 of the valve housing 310. The high-pressure, high-temperature discharge flow exerts a positive pressure on the second endcap 365, pushing the actuator assembly 360 towards the first end 306 of the valve housing 310 and into the first position (FIG. 3). In addition, the suction flow in the suction port 330 pulls a lower pressure on the suction duct 335 that propagates through the suction duct 335, the piston slider cavity 393, and the first reversing duct 345 to generate a lower pressure on the first endcap 363, pulling actuator assembly 360 towards the first end 306 of the valve housing to maintain the first position.

When the electromagnetic coil of the solenoid 382 is energized by the power source, it generates a magnetic field that pushes the piston 388 into a second piston position relative to the secondary actuation housing 381. In the second piston position (shown in FIG. 6), the spring 384 is extended, and the end 387 of the piston 388 is engaged with the end 389 of the secondary actuation housing 381. In the second piston position, the piston slider cavity 393 fluidly connects the second reversing duct 355 to the suction duct 335, and the discharge duct 325 is fluidly connected to the first reversing duct 345 through the channel formed by the secondary actuation housing 381. Thus, a portion of the discharge flow in the discharge port 320 is routed through the discharge duct 325 and the first reversing duct 345 to the valve channel 312 proximate the first end 306 of the valve housing 310. The high-pressure, high-temperature discharge flow exerts a positive pressure on the first endcap 363, pushing the actuator assembly 360 towards the second end 307 of the valve housing 310 and into the second position (FIG. 4). In addition, the suction flow in the suction port 330 pulls a lower pressure on the suction duct 335 that propagates through the suction duct 335, the piston slider cavity 393, and the second reversing duct 355 to generate a lower pressure on the second endcap 365, pulling the actuator assembly 360 towards the second end 307 of the valve housing to maintain the second position.

In both the first and second positions of the actuator assembly 360, the slider 370 is in contact with both the high-temperature discharge flow and the low-temperature suction flow. Because of the large temperature differential between the two flows, the slider 370 may permit heat transfer between them, causing the discharge flow to lose heat to the suction flow. Such a heat loss is particularly detrimental when the system 100 is operating in heating mode, because the discharge flow loses heat that could otherwise be released by the indoor heat exchanger 140 to heat the interior space 60.

A reversing valve of the present disclosure may include additional features as means for reducing or preventing heat transfer to and from the discharge flow and/or the suction flow. For example, the actuator assembly 360 may be made of thermally insulating material, such as polyether ether ketone or any suitable material with a low thermal conductivity.

Additionally or alternatively, the slider 370 may be covered in a thermally insulating material, for example but without limitation, polyether ether ketone or teflon.

Additionally or alternatively, the reversing valve 300 itself may be constructed from and/or covered by an insulating material to reduce heat losses to the exterior space 80. The insulating material may be, for example but without limitation, thermoplastic foam.

Additionally or alternatively, the thickness of the slider 370 may be increased to increase a thermal resistance of the slider 370.

Additionally or alternatively, the actuator assembly 360 may include at least one baffle (not shown) positioned between the slider 370 and the first and/or second discharge channels 364, 366, with the baffle(s) configured to separate the suction and discharge flows.

Additionally or alternatively, the discharge port may be constructed with a tapering diameter to increase or decrease a velocity of the discharge flow entering the reversing valve 300.

Additionally or alternatively, the reversing valve 300 may be constructed as a rotating four-way valve (not shown), with the actuator assembly 360 including a rotating actuator assembly (not shown).

FIGS. 7-10 illustrate a second example reversing valve 400. The second reversing valve 400 is similar to the first reversing valve 300 shown in FIGS. 3-6, and the description of the first reversing valve 300 applies to the second reversing valve 400 except where indicated otherwise. Similar to the first reversing valve shown in FIGS. 3-6, the second reversing valve 400 includes a valve housing 410 extending in a longitudinal direction from a first end 406 to a second end 407. The valve housing 410 defines a valve channel 412 extending along a length thereof. The reversing valve 400 also includes a reversing assembly 431 and a discharge inlet assembly 420.

As in the first reversing valve 300 shown in FIGS. 3-6, the reversing assembly 431 includes a suction port 430 and first and second reversing ports 440, 450. In the illustrated embodiment, the reversing assembly 431 is disposed on a suction side 418 of the valve housing 410, with the suction port 430 positioned between the first and second reversing ports 440, 450. The discharge inlet assembly 420 includes first and second discharge ports 422, 424. In the illustrated embodiment, the discharge inlet assembly 420 is disposed on a discharge side 416 of the valve housing 310 that opposes the suction side 418, with the first discharge port 422 substantially aligned with the first reversing port 440, and the second discharge port 424 substantially aligned with the second reversing port 450. In other embodiments, the ports 422-450 may have any suitable configuration relative to the valve housing 410 and each other that allows the reversing valve 300 to function as described.

Each port 422-450 extends from a first end (not labeled) connected to a surface 414 of the valve housing 410 to a second, free end. Each port 422-450 also defines a channel (not labeled) extending along a length thereof, and an opening (not labeled) in the valve housing 410 at the first end of each port 422-450.

With additional reference to FIG. 8, the reversing valve 400 also includes an actuator assembly 460 slidably disposed within the valve channel 415 along a length thereof. The actuator assembly 460 includes an actuator seat 462 and a slider 470 defining a slider cavity 472 therein. The actuator seat 462 defines a first discharge channel 464, a second discharge channel 466, and a slider opening 467 through which a portion of the slider 370 is disposed. In some embodiments (not shown), the slider 470 may also define a first slider opening and a second slider opening 376 on a side of the slider proximate the reversing assembly 431.

During operation, the actuator assembly 460 is selectively positionable in a first position or a second position. In the first position (shown in FIG. 9a), the actuator assembly 460 is positioned such that the slider 470 is situated above the first reversing port 440 and the suction port 430. In embodiments in which the slider 470 defines first and second slider openings, the first slider opening is aligned with the first reversing port 440 and the second slider opening is aligned with the suction port 430. The slider cavity 472 thus fluidly connects the first reversing port 440 to the suction port 430 when the actuator assembly 460 is in the first position. In addition, the second discharge port 424 is fluidly connected to the second reversing port 450 through the second discharge channel 466 of the actuator seat 462. The first discharge port 422 and the first discharge channel 464 remain unused when the actuator assembly 460 is positioned in the first position. In such a configuration, and with additional reference to FIG. 9b, the fluid path formed by the first reversing port 440, slider cavity 472, and suction port 430 forms a first suction path 402. The fluid path formed by the second discharge port 424, the second discharge channel 466, and the second reversing port 450 forms a first discharge path 401.

In the second position (shown in FIG. 10a), the actuator assembly 460 is positioned such that the slider 470 is situated above the suction port 430 and the second reversing port 450. In embodiments in which the slider 470 defines first and second slider openings, the first slider opening is aligned with the suction port 430 and the second slider opening is aligned with the second reversing port 450. The slider cavity 472 thus fluidly connects the suction port 430 to the second reversing port 450 when the actuator assembly 460 is in the second position. In addition, the first discharge channel 464 of the actuator seat 462 fluidly connects the first discharge port 422 to the first reversing port 440. The second discharge port 424 and the second discharge channel 466 remain unused when the actuator assembly 460 is positioned in the second position. In such a configuration, and with additional reference to FIG. 10b, the fluid path formed by the second reversing port 450, slider cavity 472, and suction port 430 forms a second suction path 404. The fluid path formed by the first discharge port 422, the first discharge channel 464, and the second reversing port 450 forms a second discharge path 403.

In some embodiments, the reversing valve 400 also includes a secondary actuation assembly (not shown) substantially similar to the secondary actuation assembly 380 shown and described with respect to the first example reversing valve 300 in FIGS. 3-6. In other embodiments, the second reversing valve 400 is controlled by any other suitable means.

With reference to FIGS. 9a-10b, the second example reversing valve 400 is constructed such that the suction path 402/404 and discharge path 401/403 do not make direct contact with any of the same components. With no significant heat transfer path between the two flow paths, the resultant heat losses between them are reduced or prevented.

FIGS. 11 and 12 are schematic diagrams of a second example vapor compression system 500 for heating or cooling an interior space 60. The second compression system 500 is substantially similar to the first vapor compression system 100 shown in FIGS. 1 and 2, and the description of the first system 100 applies to the second system 500 except where indicated otherwise. In the second system 500, the first reversing valve 300 is replaced by the second reversing valve 400. All other components remain the same or substantially the same as in the first system 100. FIG. 11 illustrates the second system 500 configured in cooling mode, with the second reversing valve 400 configured with the actuator assembly 460 in the first position. FIG. 12 illustrates the second system 500 configured in heating mode, with the second reversing valve 400 configured with the actuator assembly 460 in the second position.

The discharge and suction flows can also be isolated in a vapor compression system that uses first and second valves to reverse the system, rather than a single reversing valve. For example, FIGS. 13 and 14 are schematic diagrams of a third example vapor compression system 600 for heating or cooling an interior space 60. The third vapor compression system 600 is substantially similar to the first and second vapor compression systems 100, 500 shown in FIGS. 1-2 and 11-12, and the description of the first and second systems 100, 500 applies to the third system 600 except as indicated otherwise. Instead of the reversing valves 300, 400 of the first and second systems 100, 500, the third system 600 includes a first valve 610 and a second valve 620. The first valve 610 is a first three-way valve 610 that receives the discharge flow from the compressor exit 115, and is selectively positionable to connect the discharge flow to one of the indoor and outdoor heat exchangers 140, 120. The second valve 620 is a second three-way valve 620 that is selectively positionable to fluidly connect one of the indoor and outdoor heat exchangers 140, 120 to the suction flow. The first and second three-way valves 610, 620 may be any suitable type of three-way valve, for example and without limitation, ball valves, solenoid valves, butterfly valves, multipath plug valves. The first and second three-way valves 610, 620 may be the same type of three-way valve, or they may be different types.

With reference to FIG. 13, the third system 600 is configured to operate in cooling mode when the first three-way valve 610 is positioned to fluidly connect the discharge flow to the outdoor heat exchanger 120, and the second three-way valve 620 is positioned to fluidly connect the suction flow to the indoor heat exchanger 140. With reference to FIG. 14, the third system 600 is configured to operate in heating mode when the first three-way valve 610 is positioned to fluidly connect the discharge flow to the indoor heat exchanger 140, and the second three-way valve 620 is positioned to fluidly connect the suction flow to the outdoor heat exchanger 120. The discharge and suction flows are configured to flow through two different valves 610, 620, thereby isolating the flows and preventing heat transfer therebetween.

FIGS. 15 and 16 are schematic diagrams of a fourth example vapor compression system 700 for heating or cooling an interior space 60. The fourth vapor compression system 700 is substantially similar to the third vapor compression system 600 shown in FIGS. 13 and 14, and the description of the third system 600 applies to the fourth system 700 except as indicated otherwise. In the fourth system 700, the first three-way valve 610 is replaced with a first four-way reversing valve 710 having three open ports and one sealed port, and the second three-way valve 620 is replaced with a second four-way reversing valve 720 having three open ports and one sealed port. That is, each of the first and second four-way reversing valves 720 is configured to function as a three-way valve. In the illustrated embodiment, the first and second four-way reversing valves 710, 720 are substantially the same or similar to the first reversing valve 300 shown in FIGS. 3-6, with the discharge port and first and second reversing ports (not labeled in FIGS. 15-16) being open, and the suction port (not labeled in FIGS. 15-16) being sealed.

The first four-way reversing valve 710 receives the discharge flow from the compressor exit 115 at the discharge port (not labeled in FIGS. 15-16), and directs the discharge flow to one of the indoor and outdoor heat exchangers 140, 120 via the first or second reversing port (not labeled), respectively. The second four-way reversing valve 720 receives the suction flow from one of the indoor and outdoor heat exchangers 140, 120 via one of the first or second reversing ports (not labeled), and provides the suction flow to the compressor inlet 110 via the discharge port (not labeled).

With reference to FIG. 15, the fourth system 700 is configured to operate in cooling mode when the first four-way valve 710 is positioned to fluidly connect the discharge flow to the outdoor heat exchanger 120, and the second four-way valve 720 is positioned to fluidly connect the suction flow to the indoor heat exchanger 140. With reference to FIG. 16, the fourth system 700 is configured to operate in heating mode when the first four-way valve 710 is positioned to fluidly connect the discharge flow to the indoor heat exchanger 140, and the second four-way valve 720 is positioned to fluidly connect the suction flow to the outdoor heat exchanger 120. The discharge and suction flows are configured to flow through two different reversible valves 710, 720, thereby isolating the flows and preventing heat transfer therebetween.

FIGS. 17 and 18 are schematic diagrams of a fifth example vapor compression system 800 for heating or cooling an interior space 60. The fifth vapor compression system 800 is substantially similar to the third and fourth vapor compression systems 600, 700 shown in FIGS. 13-16, and the description of the third and fourth systems 600, 700 applies to the fifth system 800 except where indicated otherwise. In the fifth example system 800, the first valve is a first four-way reversing valve 810 having three open ports and one sealed port, and the second valve is a passive three-way valve 820.

In the illustrated embodiment, the first four-way reversing valve 810 receives the discharge flow from the compressor exit 115, and is selectively positionable to connect the discharge flow to one of the indoor and outdoor heat exchangers 140, 120. The passive three-way valve 820 is selectively positionable to fluidly connect one of the indoor and outdoor heat exchangers 140, 120 to the suction flow, which is then returned to the compressor inlet 110. The first four-way valve 810 may be substantially the same valve as the first four-way valve 710 of the fourth system 700, or it may be any other suitable valve. The passive three-way valve 820 may be a bidirectional shuttle valve or any other suitable type of passive three-way valve.

With reference to FIG. 17, the fifth system 800 is configured to operate in cooling mode when the first four-way valve 810 is positioned to fluidly connect the discharge flow to the outdoor heat exchanger 120, and the passive three-way valve 820 is positioned to fluidly connect the suction flow to the indoor heat exchanger 140. With reference to FIG. 18, the fifth system 800 is configured to operate in heating mode when the first four-way valve 810 is positioned to fluidly connect the discharge flow to the indoor heat exchanger 140, and the passive three-way valve 820 is positioned to fluidly connect the suction flow to the outdoor heat exchanger 120. The discharge and suction flows are thus configured to flow through two different reversible valves 810, 820, thereby isolating the flows and preventing heat transfer therebetween.

FIGS. 19 and 20 are schematic diagrams of a sixth example vapor compression system 900 for heating or cooling an interior space 60. The sixth vapor compression system 900 is substantially similar to the third vapor compression system 600 shown in FIGS. 13 and 14, and the description of the third system 600 applies to the sixth system 900 except where indicated otherwise. Instead of the first and second three-way valves 610, 620 of the third system 600, the first valve is a first valve assembly 910 and the second valve 920 is a second valve assembly 920. The first valve assembly 910 includes first and second solenoid valves 912, 914 installed in parallel, and the second valve assembly 920 includes third and fourth solenoid valves 922, 924 installed in parallel.

The first solenoid valve 912 is fluidly connected between the compressor exit 115 and the indoor heat exchanger 140 to provide the discharge flow thereto when the first solenoid valve 912 is open. The second solenoid valve 914 is fluidly connected between the compressor exit 115 and the outdoor heat exchanger 120 to provide the discharge flow thereto when the second solenoid valve 914 is open. The third solenoid valve 922 is fluidly connected between the indoor heat exchanger 140 and the compressor inlet 110 to provide the suction flow thereto. The fourth solenoid valve 924 is fluidly connected between the outdoor heat exchanger 120 and the compressor inlet 110 to provide the suction flow thereto.

Each solenoid valve 912-924 is selectively positionable in an open or closed position. During operation, only one valve in each of the first and second valve assemblies 910, 920 may be open at one time, and the configuration of each solenoid valve 912-924 determines the mode of operation of the system 900. With reference to FIG. 19, the sixth system 900 is configured to operate in cooling mode when the second and third solenoid valves 914, 922 are open, and the first and fourth solenoid valves 912, 924 are closed. With reference to FIG. 20, the sixth system 900 is configured to operate in heating mode when the first and fourth solenoid valves 912, 924 are open, and the second and third solenoid valves 914, 922 are closed. The discharge and suction flows are configured to flow through two of four different reversible valves 912/914, 922/924, thereby isolating the flows and preventing heat transfer therebetween.

FIGS. 21 and 22 are schematic diagrams of a seventh example vapor compression system 1000 for heating or cooling an interior space 60. The seventh vapor compression system 1000 is substantially similar to the other disclosed vapor compression systems, and the prior description of the other vapor compression systems applies to the seventh system 1000 except where indicated otherwise. In the seventh system 1000, the second valve is a second valve assembly 1020 including a third valve 1022 and a fourth valve 1024. In the illustrated embodiment, each of the first, third, and fourth valves 1010, 1022, 1024 is a first four-way reversing valve 810 having three open ports and one sealed port, similar to the first and second four-way valves in the fourth example system 700 shown in FIGS. 15 and 16.

In the illustrated embodiment, the first valve 1010 receives the discharge flow exiting the compressor exit 115 and is selectively positionable to provide the discharge flow to one of the indoor or outdoor heat exchanger 140, 120. The third valve 1022 is selectively positionable to fluidly connect the indoor heat exchanger 140 to one of the compressor inlet 110 or the outdoor heat exchanger 120. The fourth valve 1024 is selectively positionable to fluidly connect the outdoor heat exchanger 120 to one of the compressor inlet 110 or the indoor heat exchanger 140.

With reference to FIG. 21, the system is configured to operate in cooling mode when the first valve 1010 is positioned to fluidly connect the discharge flow exiting the compressor exit 115 to the outdoor heat exchanger, the fourth valve 1024 is positioned to fluidly connect the outdoor heat exchanger 120 to the indoor heat exchanger 140, and the third valve 1022 is positioned to fluidly connect the indoor heat exchanger 140 to the compressor inlet 110. With reference to FIG. 22, the system is configured to operate in heating mode when the first valve 1010 is positioned to fluidly connect the discharge flow exiting the compressor exit 115 to the indoor heat exchanger 140, the third valve 1022 is positioned to fluidly connect the indoor heat exchanger 140 to the outdoor heat exchanger 120, and the fourth valve 1024 is positioned to fluidly connect the outdoor heat exchanger 120 to the compressor inlet 110.

In both the cooling and heating modes, the seventh system 1000 can be switched from one mode to another without changing the direction of flow through the indoor and outdoor heat exchangers 140, 120. That is, refrigerant enters the indoor heat exchanger 140 through a first indoor heat exchanger port 142 and exits through a second indoor heat exchanger port 144 in both cooling and heating modes, and refrigerant enters the outdoor heat exchanger 120 through a first outdoor heat exchanger port 122 and exits through a second outdoor heat exchanger port 124 in both cooling and heating modes. Furthermore, the discharge and suction flows are configured to flow through three different reversible valves 1010, 1022, 1024, thereby isolating the flows and preventing heat transfer therebetween.

FIGS. 23 and 24 are schematic diagrams of an eighth example vapor compression system 1100 for heating or cooling an interior space 60. The eighth vapor compression system 1100 is substantially similar to the seventh vapor compression system 1000 shown in FIGS. 21 and 22, and the prior description of the seventh system 1000 applies to the eighth system 1100 except where indicated otherwise. In the eighth system 1100, the second valve is a second valve assembly 1120 including a third valve 1122, a fourth valve 1124, and a fifth valve 1126. In the illustrated embodiment, the first valve is a first four-way reversing valve 1110 having three open ports and one sealed port, and each of the third, fourth, and fifth valves 1122, 1124, 1126 is a passive three-way valve. Similar to the seventh system 1000, the eighth system 1100 can be switched from cooling mode (FIG. 23) to heating mode (FIG. 24) without changing the direction of flow through the indoor and outdoor heat exchangers 140, 120.

With reference to FIG. 25, all of the disclosed vapor compression systems include a controller 1210 programmed to control operation thereof to cool or heat the interior space 60 to a desired temperature. The controller 1210 includes a processor 1220 and a memory 1230. The memory 1230 stores instructions that program the processor 1220 to operate the vapor compression system 100-1100 to control the temperature of the interior space 60 to a temperature setpoint.

The controller 1210 is configured to control at least one operating parameter of the vapor compression system 100-1100, for example and without limitation, a speed of the first or second fan 150, 190, a position of an expansion device 130, 135, a position of a three-way valve 610, 620, 820, 1122, 1124, 1126, a position of a solenoid valve 912, 914, 922, 924, a position of a four-way valve 300, 400, 710, 720, 810, 820, 1010, 1022, 1024, or a speed of the compressor 160.

For example, in the first example vapor compression system 100, the controller 1210 is configured to control the position of the first example reversing valve 300 to direct the discharge flow to either the indoor or outdoor heat exchanger 140, 120. When the controller programs operation of the first example vapor compression system 100 to direct the discharge flow to the outdoor heat exchanger, the controller 1210 is additionally configured to bypass the second expansion device 135. The controller 1210 may control these parameters in response to at least one measured or calculated property of the air in the conditioned interior space 50, for example and without limitation, a dew point temperature, wet bulb temperature, partial pressure of water vapor, or humidity ratio.

The vapor compression system 100-1100 also includes a user interface 1240 configured to output (e.g., display) and/or receive information (e.g., from a user) associated with the vapor compression system 100-1100. In some embodiments, the user interface 1240 is configured to receive an activation and/or deactivation input from a user to activate and deactivate (i.e., turn on and off) or otherwise enable operation of the vapor compression system 100-1100. For example, the user interface 1240 can receive a temperature setpoint specified by the user. Moreover, in some embodiments, the user interface 1240 is configured to output information associated with one or more operational characteristics of the vapor compression system 100-1100, including, for example and without limitation, warning indicators such as severity alerts, occurrence alerts, fault alerts, motor speed alerts, and any other suitable information.

The user interface 1240 may include any suitable input devices and output devices that enable the user interface 1240 to function as described. For example, the user interface 1240 may include input devices including, but not limited to, a keyboard, mouse, touchscreen, joystick(s), throttle(s), buttons, switches, and/or other input devices. Moreover, the user interface 540 may include output devices including, for example and without limitation, a display (e.g., a liquid crystal display (LCD) or an organic light emitting diode (OLED) display), speakers, indicator lights, instruments, and/or other output devices. Furthermore, the user interface 1240 may be part of a different component, such as a system controller (not shown). Other embodiments do not include a user interface 1240.

The controller 1210 is generally configured to control operation of the vapor compression system 100-1100. The controller 1210 controls operation through programming and instructions from another device or controller or is integrated with the conditioning system 300 through a system controller. In some embodiments, for example, the controller 1210 receives user input from the user interface 1240, and controls one or more components of the vapor compression system 100-1100 in response to such user inputs. For example, the controller 1210 may control the first fan 150 based on user input received from the user interface 1240. The vapor compression system 100-1100 is suitably controlled such as by a remote control interface. For example, the vapor compression system 100-1100 may include a communication interface 1250 configured for connection to a wireless control interface (not shown) that enables remote control and activation of the vapor compression system 100-1100. The wireless control interface may be embodied on a portable computing device, such as a tablet or smartphone.

The controller 1210 may generally include any suitable computer and/or other processing unit, including any suitable combination of computers, processing units and/or the like that may be communicatively coupled to one another and that may be operated independently or in connection within one another (e.g., controller 1210 may form all or part of a controller network). Controller 1210 may include one or more modules or devices, one or more of which is enclosed within the vapor compression system 100-1100, or may be located remote from the vapor compression system 100-1100. The controller 1210 may be part of the vapor compression system 100-1100, or it may be part of a system controller in an HVAC system. Controller 1210 and/or components of controller 1210 may be integrated or incorporated within other components of the vapor compression system 100-1100. The controller 1210 may include one or more processor(s) 1220 and associated memory device(s) 1230 configured to perform a variety of computer-implemented functions (e.g., performing the disclosed calculations, determinations, and functions).

The term “processor” refers not only to integrated circuits, but also to a controller, a microcontroller, a microcomputer, a programmable logic controller (PLC), an application-specific integrated circuit, and other programmable circuits. Additionally, memory device(s) 1230 of controller 1210 may generally be or include memory element(s) including, but not limited to, computer readable medium (e.g., random access memory (RAM)), computer readable non-volatile medium (e.g., a flash memory), a floppy disk, a compact disc-read only memory (CD-ROM), a magneto-optical disk (MOD), a digital versatile disc (DVD) and/or other suitable memory elements. Such memory device(s) 1230 may generally be configured to store suitable computer-readable instructions that, when implemented by the processor(s) 1220, configure or cause the controller 1210 to perform various functions including, but not limited to, controlling the vapor compression system 100-1100, receiving inputs from user interface 1240, providing output to an operator via user interface 1240, and/or various other suitable computer-implemented functions.

Technical benefits of the disclosed systems and apparatuses are as follows: (1) a four-way reversing valve is constructed to isolate the suction and discharge flows, either by physical distance or thermal insulation, and (2) a vapor compression system is designed to isolate the suction and discharge flows by flowing them through separate valves.

The terms “about,” “substantially,” “essentially” and “approximately” when used in conjunction with ranges of dimensions, concentrations, temperatures or other physical or chemical properties or characteristics is meant to cover variations that may exist in the upper and/or lower limits of the ranges of the properties or characteristics, including, for example, variations resulting from rounding, measurement methodology or other statistical variation.

When introducing elements of the present disclosure or the embodiment(s) thereof, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” “containing,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. The use of terms indicating a particular orientation (e.g., “top,” “bottom,” “side,” etc.) is for convenience of description and does not require any particular orientation of the item described.

As various changes could be made in the above constructions and methods without departing from the scope of the disclosure, it is intended that all matter contained in the above description and shown in the accompanying drawing[s] shall be interpreted as illustrative and not in a limiting sense.

Claims

1. A vapor compression system comprising:

an indoor heat exchanger;

an outdoor heat exchanger;

a compressor having an inlet fluidly connected to a suction flow and an exit fluidly connected to a discharge flow;

a first valve selectively positionable to fluidly connect the discharge flow to one of the indoor and outdoor heat exchangers; and

a second valve selectively positionable to fluidly connect the suction flow to one of the indoor and outdoor heat exchangers.

2. The vapor compression system of claim 1, wherein the system is configured to operate in a heating mode when the first valve is positioned to fluidly connect the discharge flow to the indoor heat exchanger and the second valve is positioned to fluidly connect the suction flow to the outdoor heat exchanger.

3. The vapor compression system of claim 1, wherein the system is configured to operate in a cooling mode when the first valve is positioned to fluidly connect the discharge flow to the outdoor heat exchanger and the second valve is positioned to fluidly connect the suction flow to the indoor heat exchanger.

4. The vapor compression system of claim 1, wherein the first valve comprises a first three-way valve, and wherein the second valve comprises a second three-way valve.

5. The vapor compression system of claim 1, wherein the first valve comprises a first four-way reversing valve having three open ports and one sealed port, and wherein the second valve comprises a second four-way reversing valve having three open ports and one sealed port.

6. The vapor compression system of claim 1, wherein the first valve comprises a first four-way reversing valve having three open ports and one sealed port, and wherein the second valve comprises a passive three-way valve.

7. The vapor compression system of claim 1, wherein the first valve is a first valve assembly comprising first and second solenoid valves installed in parallel, and wherein the second valve is a second valve assembly comprising third and fourth solenoid valves installed in parallel.

8. The vapor compression system of claim 1, wherein the system is configured to operate in a heating mode when the first valve is positioned to fluidly connect the discharge flow to the indoor heat exchanger, wherein the system is configured to operate in a cooling mode when the first valve is positioned to fluidly connect the discharge flow to the outdoor heat exchanger, and wherein the system is operable in heating or cooling mode without changing a direction of flow through the indoor and outdoor heat exchangers.

9. The vapor compression system of claim 1, wherein the second valve is a second valve assembly comprising a third valve fluidly connected to the indoor heat exchanger and a fourth valve fluidly connected to the outdoor heat exchanger, wherein the third valve is selectively positionable to fluidly connect the indoor heat exchanger to one of the compressor inlet or the outdoor heat exchanger, and wherein the fourth valve is selectively positionable to fluidly connect the outdoor heat exchanger to one of the compressor inlet or the indoor heat exchanger.

10. A reversing valve comprising:

a valve housing defining a valve channel along a length thereof;

a discharge inlet assembly comprising first and second discharge ports extending from a surface of the valve housing;

a reversing assembly comprising: first and second reversing ports extending from the surface of the valve housing; and a suction port extending from the surface of the valve housing between the first and second reversing ports; and

an actuator assembly slidably disposed within the valve channel and selectively positionable between a first position, wherein the first discharge port is fluidly connected to the first reversing port, and a second position, wherein the second discharge port is fluidly connected to the second reversing port.

11. The reversing valve of claim 10, wherein the actuator assembly further comprises an actuator seat defining a first discharge channel and a second discharge channel, wherein the first discharge channel fluidly connects the first discharge port to the first reversing port when the actuator assembly is in the first position, and wherein the second discharge channel fluidly connects the second discharge port to the second reversing port when the actuator assembly is in the second position.

12. The reversing valve of claim 10 further comprising a solenoid valve configured to control the actuator assembly.

13. The reversing valve of claim 10, wherein the actuator assembly further comprises a slider defining a cavity therein, wherein the slider cavity fluidly connects the second reversing port to the suction port when the actuator assembly is in the first position, and wherein the slider cavity fluidly connects the first reversing port to the suction port when the actuator assembly is in the second position.

14. A reversible vapor compression system comprising the reversing valve of claim 10, wherein the system is configured to operate in cooling mode when the actuator assembly is in the first position, and wherein the system is configured to operate in heating mode when the actuator assembly is in the second position.

15. A reversing valve comprising:

a first reversing port;

a second reversing port;

a discharge port for providing a discharge flow to one of the first and second reversing ports;

a suction port for receiving a suction flow from one of the first and second reversing ports; and

means for reducing heat transfer to and from the discharge flow and/or the suction flow.

16. The reversing valve of claim 15 further comprising an actuator assembly selectively positionable in a first position, in which the discharge port provides the discharge flow to the first reversing port and the second reversing port provides the suction flow to the suction port, and a second position, in which the discharge port provides the discharge flow to the second reversing port and the first reversing port provides the suction flow to the suction port.

17. The reversing valve of claim 16, wherein the actuator assembly is constructed from a thermally insulating material.

18. The reversing valve of claim 16, wherein the reversing valve is a rotating four-way valve, and the actuator assembly is a rotating actuator assembly.

19. The reversing valve of claim 15, wherein the means for reducing heat transfer comprises a baffle configured to separate the suction and discharge flows.

20. The reversing valve of claim 15, wherein the discharge port is constructed with a tapering diameter configured to increase or decrease a velocity of the discharge flow.