The present subject matter relates generally to heat pump systems, such as packaged terminal air conditioner units, and sealed systems for the same.
Certain packaged terminal air conditioner units include a sealed system for chilling and/or heating air. The sealed systems include various components for treating a refrigerant in order to cool or heat air. The sealed system components are generally positioned within a casing that can be mounted within a wall or window of an associated building. Due to space constraints within the casing, selection of sealed system components for packaged terminal air conditioner units can be limited to relatively small components.
Packaged terminal air conditioner units are frequently classified and sold by efficiency. Customers generally prefer efficient packaged terminal air conditioner units because small improvements in heating and cooling efficiency can provide a significant reduction in utility bills. Energy efficiency in packaged terminal air conditioner units is generally a function of compressor size and efficiency, heat exchanger size, design and airflow and fan design among other factors. However, high efficiency compressors are typically very expensive, and large heat exchangers may not fit within the limited space available in the casing of a packaged terminal air conditioner unit.
Accordingly, a packaged terminal air conditioner unit with features for assisting with increasing an efficiency of the packaged terminal air conditioner would be useful. In particular, a packaged terminal air conditioner unit with features for assisting with increasing an efficiency of the packaged terminal air conditioner without requiring a high efficiency compressor and/or a large heat exchanger would be useful.
The present subject matter provides a packaged terminal air conditioner unit with a casing. A compressor, a reversing valve and an ejector of the packaged terminal air conditioner unit are positioned within the casing. The ejector is configured for drawing vapor refrigerant into a flow of liquid refrigerant. An exterior heat exchanger and an interior heat exchanger are also positioned within the casing. The interior heat exchanger has a first stage and a second stage. Additional aspects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention.
In a first exemplary embodiment, a packaged terminal air conditioner unit is provided. The packaged terminal air conditioner unit includes a casing. A compressor is positioned within the casing. The compressor is operable to increase a pressure of a refrigerant. An interior heat exchanger is positioned within the casing. The interior heat exchanger has a first stage and a second stage that are separate from each other. An exterior heat exchanger is positioned within the casing opposite the interior heat exchanger. A phase separator is positioned within the casing. The phase separator is configured for separating liquid refrigerant from vapor refrigerant. A reversing valve is positioned within the casing. The reversing valve is in fluid communication with the compressor in order to receive compressed refrigerant from the compressor. The reversing valve is configured for selectively directing the compressed refrigerant from the compressor to the exterior heat exchanger or the second stage of the interior heat exchanger. A supply conduit extends between the exterior heat exchanger and the phase separator. An ejector is coupled to the supply conduit. A first distribution conduit extends between the first stage of the interior heat exchanger and the ejector. A second distribution conduit extends between the exterior heat exchanger and the first stage of the interior heat exchanger. A connection conduit extends between the phase separator and the second stage of the interior heat exchanger. A bypass conduit extends from the phase separator around the second stage of the interior heat exchanger.
In a second exemplary embodiment, a packaged terminal air conditioner unit is provided. The packaged terminal air conditioner unit includes a casing that extends between an exterior side portion and an interior side portion. A compressor is positioned within the casing. The compressor is operable to compress a refrigerant. An interior heat exchanger is positioned within the casing at the interior side portion of the casing. The interior heat exchanger has a first stage and a second stage that are separate from each other. An exterior heat exchanger is positioned within the casing at the exterior side portion of the casing. A reversing valve is in fluid communication with the compressor in order to receive compressed refrigerant from the compressor. A phase separator is positioned within the casing. The phase separator is configured for separating liquid refrigerant from vapor refrigerant. An ejector is positioned within the casing. The packaged terminal air conditioner unit is configured such that, in a cooling mode, a flow of liquid refrigerant from the exterior heat exchanger flows through the ejector and the ejector draws vapor refrigerant from the first stage of the interior heat exchanger into the flow of liquid refrigerant and a combined flow of liquid and vapor refrigerant flows from the ejector to the phase separator. Vapor refrigerant from the phase separator flows around the second stage of the interior heat exchanger to the compressor and liquid refrigerant from the phase separator flows to the second stage of the interior heat exchanger in the cooling mode. The packaged terminal air conditioner unit is also configured such that, in a heating mode, refrigerant from the second stage of the interior heat exchanger flows through the phase separator and the ejector to the first stage of the interior heat exchanger.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures.
Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
As may be seen in
Casing 110 defines a mechanical compartment 116. Sealed system 120 is disposed or positioned within mechanical compartment 116 of casing 110. A front panel 118 and a rear grill or screen 119 are mounted to casing 110 and hinder or limit access to mechanical compartment 116 of casing 110. Front panel 118 is mounted to casing 110 at interior side portion 112 of casing 110, and rear screen 119 is mounted to casing 110 at exterior side portion 114 of casing 110. Front panel 118 and rear screen 119 each define a plurality of holes that permit air to flow through front panel 118 and rear screen 119, with the holes sized for preventing foreign objects from passing through front panel 118 and rear screen 119 into mechanical compartment 116 of casing 110.
Packaged terminal air conditioner unit 100 also includes a drain pan or bottom tray 138 and an inner wall 140 positioned within mechanical compartment 116 of casing 110. Sealed system 120 is positioned on bottom tray 138. Thus, liquid runoff from sealed system 120 may flow into and collect within bottom tray 138. Inner wall 140 may be mounted to bottom tray 138 and extend upwardly from bottom tray 138 to a top wall of casing 110. Inner wall 140 limits or prevents air flow between interior side portion 112 of casing 110 and exterior side portion 114 of casing 110 within mechanical compartment 116 of casing 110. Thus, inner wall 140 may divide mechanical compartment 116 of casing 110.
Packaged terminal air conditioner unit 100 further includes a controller 146 with user inputs, such as buttons, switches and/or dials. Controller 146 regulates operation of packaged terminal air conditioner unit 100. Thus, controller 146 is in operative communication with various components of packaged terminal air conditioner unit 100, such as components of sealed system 120 and/or a temperature sensor, such as a thermistor or thermocouple, for measuring the temperature of the interior atmosphere. In particular, controller 146 may selectively activate sealed system 120 in order to chill or heat air within sealed system 120, e.g., in response to temperature measurements from the temperature sensor.
Controller 146 includes memory and one or more processing devices such as microprocessors, CPUs or the like, such as general or special purpose microprocessors operable to execute programming instructions or micro-control code associated with operation of packaged terminal air conditioner unit 100. The memory can represent random access memory such as DRAM, or read only memory such as ROM or FLASH. The processor executes programming instructions stored in the memory. The memory can be a separate component from the processor or can be included onboard within the processor. Alternatively, controller 146 may be constructed without using a microprocessor, e.g., using a combination of discrete analog and/or digital logic circuitry (such as switches, amplifiers, integrators, comparators, flip-flops, AND gates, and the like) to perform control functionality instead of relying upon software.
Sealed system 200 generally operates in a heat pump cycle. Sealed system 200 includes a compressor 210, an interior heat exchanger or coil 212 and an exterior heat exchanger or coil 214. As is generally understood, various conduits may be utilized to flow refrigerant between the various components of sealed system 200, as discussed in greater detail below. Thus, e.g., interior coil 212 and exterior coil 214 may be between and in fluid communication with each other and compressor 210 via suitable tubing or piping.
As may be seen in
As may be seen in
As shown in
Exterior coil 214 is disposed downstream of compressor 210 in the cooling mode and acts as a condenser. Thus, exterior coil 214 is operable to reject heat into the exterior atmosphere, e.g., at exterior side portion 114 of casing 110, when sealed system 200 is operating in the cooling mode. For example, the superheated vapor from compressor 210 may enter exterior coil 214 via suitable conduit or piping that extends between and fluidly connects reversing valve 216 and exterior coil 214. Within exterior coil 214, the refrigerant from compressor 210 transfers energy to the exterior atmosphere and condenses into a saturated liquid, liquid vapor mixture and/or subcooled liquid. An exterior air handler or fan 230 positioned adjacent exterior coil 214 may facilitate or urge a flow of air from the exterior atmosphere across exterior coil 214 in order to facilitate heat transfer.
As may be seen in
As shown in
It should be understood that phase separator 222 may be any suitable type of phase separator. For example, phase separator 222 may be constructed in the same or similar manner to the phase separator described in U.S. patent application Ser. No. 14/088,558 of Brent Alden Junge and/or the phase separator described in U.S. patent application Ser. No. 14/258,397 of Brent Alden Junge et al., both of which are incorporated by reference herein for all purposes. Within a casing of phase separator 222, liquid phase refrigerant may collect or pool at a bottom portion of phase separator 222 and vapor phase refrigerant may collect or pool at a top portion of phase separator 222, e.g., due to density differences between the liquid and vapor phase refrigerants.
Sealed system 200 also includes a connection conduit 240. As may be seen in
A throttling device 220 is disposed on a second distribution conduit 242. Second distribution conduit 242 extends between exterior coil 214 and first stage 250 of interior coil 212. Throttling device 220 is positioned between exterior coil 214 and first stage 250 of interior coil 212 on second distribution conduit 242. In the cooling mode, refrigerant from exterior coil 214 travels through throttling device 220 before flowing through first stage 250 of interior coil 212. Throttling device 220 may generally expand the refrigerant, lowering the pressure and temperature thereof. Throttling device 220 (e.g., and any other throttling device described herein) may include various components for throttling refrigerant flow through second distribution conduit 242. For example, throttling device 220 (e.g., and any other throttling device described herein) may include a capillary tube and check valve, a J-T valve, an electronic expansion valve, etc. to throttle the flow of refrigerant through second distribution conduit 242, as will be understood by those skilled in the art.
First stage 250 of interior coil 212 is disposed downstream of throttling device 220 in the cooling mode and acts as an evaporator. Thus, first stage 250 of interior coil 212 is operable to heat refrigerant within first stage 250 of interior coil 212 with energy from the interior atmosphere, e.g., at interior side portion 112 of casing 110, when sealed system 200 is operating in the cooling mode. For example, within first stage 250 of interior coil 212, the refrigerant from throttling device 220 receives energy from the interior atmosphere and vaporizes into superheated vapor and/or high quality vapor-liquid mixture. An interior air handler or fan 228 positioned adjacent first stage 250 of interior coil 212 may facilitate or urge a flow of air from the interior atmosphere across first stage 250 of interior coil 212 in order to facilitate heat transfer. As discussed above, ejector 232 directs the vapor refrigerant from interior coil 212 into supply conduit 234.
Like first stage 250 of interior coil 212, second stage 252 of interior coil 212 acts as an evaporator in the cooling mode; however, second stage 252 of interior coil 212 is disposed downstream of phase separator 222 in the cooling mode. Thus, second stage 252 of interior coil 212 is operable to heat refrigerant within second stage 252 of interior coil 212 with energy from the interior atmosphere, e.g., at interior side portion 112 of casing 110, when sealed system 200 is operating in the cooling mode. For example, within second stage 252 of interior coil 212, the liquid refrigerant from phase separator 222 receives energy from the interior atmosphere and vaporizes into superheated vapor and/or high quality vapor-liquid mixture. Interior fan 228 positioned adjacent second stage 252 of interior coil 212 may facilitate or urge a flow of air from the interior atmosphere across second stage 252 of interior coil 212 in order to facilitate heat transfer.
During operation of sealed system 200 in the heating mode, reversing valve 216 reverses the direction of refrigerant flow through sealed system 200, as shown in
As may be seen in
Exterior coil 214 is disposed downstream of throttling device 220 in the heating mode and acts as an evaporator. Thus, exterior coil 214 is operable to heat refrigerant within exterior coil 214 with energy from the exterior atmosphere, e.g., at exterior side portion 114 of casing 110, when sealed system 200 is operating in the heating mode. For example, within exterior coil 214, the refrigerant from throttling device 220 receives energy from the exterior atmosphere and vaporizes into superheated vapor and/or high quality vapor-liquid mixture. From exterior coil 214, refrigerant is directed back to compressor 210.
Sealed system 200 may assist with operating packaged terminal air conditioner unit 100 efficiently. For example, ejector 232 of sealed system 200 may utilize expansion work of high-pressure refrigerant to compress vapor refrigerant exiting first stage 250 of interior coil 212 in the cooling mode. In such a manner, ejector 232 may assist with reducing energy consumption of compressor 210 in the cooling mode. Phase separator 222 also reduces a pressure drop in second stage 252 of interior coil 212 by bypassing vapor refrigerant directly to compressor 210 in the cooling mode.
Like sealed system 200 (
As shown in
First stage 354 of exterior coil 314 is disposed downstream of compressor 310 in the cooling mode and acts as a condenser. Thus, first stage 354 of exterior coil 314 is operable to reject heat into the exterior atmosphere, e.g., at exterior side portion 114 of casing 110, when sealed system 300 is operating in the cooling mode. Within first stage 354 of exterior coil 314, the refrigerant from compressor 310 transfers energy to the exterior atmosphere and condenses into a saturated liquid and/or liquid vapor mixture. An exterior air handler or fan 330 positioned adjacent first stage 354 of exterior coil 314 may facilitate or urge a flow of air from the exterior atmosphere across first stage 354 of exterior coil 314 in order to facilitate heat transfer.
Sealed system 300 also includes a first injector or ejector 332 and a second injector or ejector 334. As may be seen in
First ejector 332 is disposed downstream of second stage 356 of exterior coil 314, in the cooling mode, and is configured for introducing or injecting vapor refrigerant from first stage 350 of interior coil 312 into the flow of refrigerant from second stage 356 of exterior coil 314. In particular, first ejector 332 may be configured for combining streams of refrigerant via the Venturi effect. Second stage 352 of interior coil 312 is positioned downstream of first ejector 332 and receives the combined flow of refrigerant from first ejector 332 in the cooling mode.
Sealed system 300 also includes various throttling devices and/or check valves. In particular, sealed system 300 includes a throttling device 338, a first check valve 346 and a second check valve 348. Throttling device 338 is disposed between second stage 356 of exterior coil 314 and first stage 350 of interior coil 312 in the cooling mode. In the cooling mode, refrigerant from second stage 356 of exterior coil 314 travels through throttling device 338 before flowing to first stage 350 of interior coil 312. Throttling device 338 may generally expand the refrigerant, lowering the pressure and temperature thereof. The refrigerant may then be flowed to first stage 350 of interior coil 312. In the cooling mode, second check valve 348 may hinder or prevent refrigerant from first stage 354 of exterior coil 314 from bypassing second stage 356 of exterior coil 314 and/or throttling device 338.
First stage 350 of interior coil 312 is disposed downstream of throttling device 338 in the cooling mode and acts as an evaporator. Similarly, second stage 352 of interior coil 312 is disposed downstream of first ejector 332 in the cooling mode and also acts as an evaporator. Thus, first and second stages 350, 352 of interior coil 312 are operable to heat refrigerant within interior coil 312 with energy from the interior atmosphere, e.g., at interior side portion 112 of casing 110, when sealed system 300 is operating in the cooling mode. For example, within first stage 350 of interior coil 312, the refrigerant from throttling device 338 receives energy from the interior atmosphere and vaporizes into superheated vapor and/or high quality vapor-liquid mixture. Similarly, within second stage 352 of interior coil 312, the refrigerant from first ejector 332 receives energy from the interior atmosphere and vaporizes into superheated vapor and/or high quality vapor-liquid mixture. An interior air handler or fan 328 positioned adjacent first and second stages 350, 352 of interior coil 312 may facilitate or urge a flow of air from the interior atmosphere across first and second stages 350, 352 of interior coil 312 in order to facilitate heat transfer.
During operation of sealed system 300 in the heating mode, reversing valve 316 reverses the direction of refrigerant flow through sealed system 300, as shown in
As may be seen in
Second ejector 334 is disposed downstream of first stage 350 of interior coil 312, in the heating mode, and is configured for introducing or injecting vapor refrigerant from second stage 356 of exterior coil 314 into the flow of refrigerant from first stage 350 of interior coil 312. In particular, second ejector 334 may be configured for combining streams of refrigerant via the Venturi effect. First stage 354 of exterior coil 314 is positioned downstream of second ejector 334 and receives the combined flow of refrigerant from second ejector 334 in the heating mode.
Throttling device 338 is disposed between first stage 350 of interior coil 312 and second stage 356 of exterior coil 314 in the heating mode. In the heating mode, refrigerant from first stage 350 of interior coil 312 travels through throttling device 338 before flowing to second stage 356 of exterior coil 314. Throttling device 338 may generally expand the refrigerant, lowering the pressure and temperature thereof. The refrigerant may then be flowed to second stage 356 of exterior coil 314. In the heating mode, first check valve 346 may hinder or prevent refrigerant from second stage 352 of interior coil 312 from bypassing first stage 350 of interior coil 312 and/or throttling device 338.
Second stage 356 of exterior coil 314 is disposed downstream of throttling device 338 in the heating mode and acts as an evaporator. Similarly, first stage 354 of exterior coil 314 is disposed downstream of second ejector 334 in the heating mode and also acts as an evaporator. Thus, first and second stages 354, 356 of exterior coil 314 are operable to heat refrigerant within exterior coil 314 with energy from the exterior atmosphere, e.g., at exterior side portion 114 of casing 110, when sealed system 300 is operating in the heating mode. For example, within second stage 356 of exterior coil 314, the refrigerant from throttling device 338 receives energy from the exterior atmosphere and vaporizes into superheated vapor and/or high quality vapor-liquid mixture. Similarly, within first stage 354 of exterior coil 314, the refrigerant from second ejector 334 receives energy from the exterior atmosphere and vaporizes into superheated vapor and/or high quality vapor-liquid mixture.
Sealed system 300 may assist with operating packaged terminal air conditioner unit 100 efficiently. For example, first and second ejectors 332, 334 of sealed system 300 may utilize expansion work of high-pressure refrigerant to compress vapor refrigerant exiting first stage 350 of interior coil 312 in the cooling mode and second stage 356 of exterior coil 314 in the heating mode. In such a manner, first and second ejectors 332, 334 may assist with reducing energy consumption of compressor 310 in the cooling and heating modes.
Like sealed system 300 (
Sealed system 400 also includes a first phase separator 422, a second phase separator 424, a third check valve 447 and a fourth check valve 449. First and second phase separators 422, 424 are configured for separating liquid refrigerant within first and second phase separators 422, 424 from vapor refrigerant within first and second phase separators 422, 424.
In the cooling mode, second phase separator 424 receives refrigerant from second ejector 434 and separates liquid refrigerant from vapor refrigerant. The liquid phase refrigerant within second phase separator 424 is directed from second phase separator 424 to second stage 452 of interior coil 412. Conversely, the vapor phase refrigerant within second phase separator 424 is directed around second stage 452 of interior coil 412 back to compressor 410 such that the vapor phase refrigerant bypasses second stage 452 of interior coil 412 in the cooling mode. As may be seen in
In the heating mode, first phase separator 422 receives refrigerant from first ejector 432 and separates liquid refrigerant from vapor refrigerant. The liquid phase refrigerant within first phase separator 422 is directed from first phase separator 422 to first stage 454 of exterior coil 414. Conversely, the vapor phase refrigerant within first phase separator 422 is directed around first stage 454 of exterior coil 414 back to compressor 410 such that the vapor phase refrigerant bypasses first stage 454 of exterior coil 414 in the heating mode. As may be seen in
Sealed system 400 may assist with operating packaged terminal air conditioner unit 100 efficiently. For example, first and second ejectors 432, 434 of sealed system 400 may utilize expansion work of high-pressure refrigerant to compress vapor refrigerant exiting first stage 450 of interior coil 412 in the cooling mode and second stage 456 of exterior coil 414 in the heating mode. In such a manner, first and second ejectors 432, 434 may assist with reducing energy consumption of compressor 410 in the heating and cooling modes. First and second phase separators 422, 424 also reduce a pressure drop in second stage 452 of interior coil 412 and first stage 454 of exterior coil 414 by bypassing vapor refrigerant directly to compressor 410 in the heating and cooling modes.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.