BACKGROUND

[0001] Heat pumps have been used to transfer thermal energy from a source of heat to supply heat to another area. Accordingly, heat pumps may be used to remove waste heat, such as heat generated from machinery or other sources that give off heat during operation, and transfer the heat to supply thermal energy for another application, such as space heating, water heating, or for other applications that use a heat source. Since heat pumps actively move thermal energy using a refrigeration cycle, it is possible to transfer heat against the direction of thermal energy flow to allow for the transfer of heat from a cooler side to a warmer side. By providing for the transfer of heat in the opposite direction of normal heat transfer, heat pumps are widely used to cool spaces, such as refrigerators and air conditioners.

[0002] Due to the relatively cheap cost of energy, heat pumps have generally not been used for heating applications. This is generally due to the increased cost of machinery involved with the heat pump that is to be regularly maintenanced as well as higher initial startup costs. For example, it is generally cheaper to generate heat from fuel, such as burning hydrocarbons, or to use resistive heating from electricity.

BRIEF DESCRIPTION OF THE DRAWINGS

[0003] Reference will now be made, by way of example only, to the accompanying drawings in which:

[0004] Figure 1 is a schematic view of an example of an apparatus to supply heat via multiple outputs at different temperatures; [0005] Figure 2 is a schematic view of another example of an apparatus to supply heat via multiple outputs at different temperatures;

[0006] Figure 3 is a schematic view of another example of an apparatus to supply heat via multiple outputs at different temperatures;

[0007] Figure 4 is a schematic view of another example of an apparatus to supply heat via multiple outputs at different temperatures;

[0008] Figure 5 is a schematic view of another example of an apparatus to supply heat via multiple outputs at different temperatures;

[0009] Figure 6 is a schematic view of another example of an apparatus to supply heat via multiple outputs at different temperatures;

[0010] Figure ? is an energy curve diagram showing the operation of the apparatus shown in figure 1;

[0011] Figure s is a schematic view of an example of a system to supply heat via multiple outputs at different temperatures using a heat pump; and

[0012] Figure 9 is a flowchart of an example of a method of supplying heat via multiple outputs at different temperatures.

DETAILED DESCRIPTION

[0013] As used herein, any usage of terms that suggest an absolute orientation (e.g. “top”, “bottom”, “up”, “down”, “left”, “right”, “low”, “high”, etc.) may be for illustrative convenience and refer to the orientation shown in a particular figure. However, such terms are not to be construed in a limiting sense as it is contemplated that various components will, in practice, be utilized in orientations that are the same as, or different than, those described or shown. [0014] Heat pumps are used for climate control purposes as well as to regulate temperature such as for a cold storage device, like a refrigerator or freezer. In these applications, the heat pump draws heat from one side of the heat pump and delivers it to the other side. Accordingly, by removing heat from a space and delivering it to the other side, the heat pump has an effect of cooling one side and heating another side and can operate against normal thermal flow, such as moving heat from a cold space to a warmer space.

[0015] Heat pumps are not widely used to provide heating to a space, such as to heat an interior space in a cold climate despite being an energy efficient manner by which a space can be heated. Instead, space heating is generally carried out by burning fuel, such as hydrocarbons in a furnace or wood and other combustibles in a stove. In many locations, it is even preferable to use electricity to generate resistive heating rather than to use less electricity to pump the same amount of heat to a space. One of the reasons heat pumps have not been used in heating applications is the setup cost and maintenance cost of a heat pump system. For example, heat pump systems include compressors, evaporators, refrigerant lines, and various valves making it a complicated system compared to a resistive heating element. However, as the cost of electricity increases along with environmental pressures to use electricity more efficiently, as well as pressures to reduce greenhouse gas emissions from the burning of fuel, more efficient methods to heat a space, such as with heat pumps, are to be considered.

[0016] In general, heat pumps can operate as a heat supply by passing a hot refrigerant in the form of a vapor into a condenser. The condenser receives a cool fluid, such as air or water, and provides thermal contact between the refrigerant and the fluid. Accordingly, the hot refrigerant vapor will transfer heat energy to the fluid to heat the fluid as the refrigerant condenses to a liquid. An apparatus is provided to a heat pump system providing a dual temperature output from a heat supply using a single refrigerant circuit. Accordingly, the apparatus can provide heat for multiple applications, such as for heating a living space and for appliances that use heat, such as a clothes dryer or oven.

[0017] Referring to figure 1 , an apparatus 50 to supply heat via multiple outputs at different temperatures is generally shown. It is to be appreciated by a person of skill with the benefit of this description that the apparatus 50 may include variants with additional features and take different forms. In the present example, the apparatus 50 includes a refrigerant inlet 55, a refrigerant outlet 60, a heat exchanger 65, a fluid inlet 70, a fluid outlet 75, and another fluid outlet 80.

[0018] The refrigerant inlet 55 is to receive a refrigerant. In the present example, the refrigerant received at the refrigerant inlet 55 is in the form of a vapor. The refrigerant flows through a compartment 62 that is sealed from the external environment to the refrigerant outlet 60 where the refrigerant leaves the compartment 62. As the refrigerant travels through the compartment 62 from the refrigerant inlet 55 to the refrigerant outlet 60, the refrigerant loses heat. Accordingly, the refrigerant condenses and decreases in temperature as it gives off heat until the boiling point of the refrigerant. At the boiling point, the refrigerant continues to give off heat through the transition from vapor refrigerant to liquid refrigerant. The liquid refrigerant continues to give off heat until it is released from the compartment 62 via the refrigerant outlet 60. It is to be appreciated by a person of skill with the benefit of this description that the liquid refrigerant may simply be collected and drained from the compartment 62 via gravity or may be pumped out with a pump that circulates the refrigerant through a closed circuit. Furthermore, although the present example describes a refrigerant that changes phases from a vapor to a liquid as it travels through the compartment 62, other examples may use a supercritical refrigerant, such as carbon dioxide, where there is no phase change at fixed conditions.

[0019] The heat exchanger 65 is to absorb the heat from the refrigerant in the compartment 62 and to transfer the heat to a fluid in the compartment 72. It is to be appreciated by a person of skill with the benefit of this description that the heat exchanger 65 includes a hot portion 67, a warm portion 68, and a cold portion 69. In the present example, the hot portion 67 may be generally defined as the portion of the heat exchanger 65 that is in thermal contact with the portion of the compartment 62 that contains the refrigerant in its vapor form. The warm portion 68 may be generally defined as the portion of the heat exchanger 65 that is in thermal contact with the portion of the compartment 62 that contains a refrigerant that is in a state where there is a mixture of liquid refrigerant and vapor refrigerant. In other words, the warm portion 68 can be considered the portion of the compartment 62 where the refrigerant is in transition from the vapor state to the liquid state and releasing its latent heat. The cold portion 69 may be generally defined as the portion of the heat exchanger 65 that is in thermal contact with the portion of the compartment 62 that contains the refrigerant in its liquid form. In this section, the refrigerant is at its lowest temperature prior to leaving the apparatus 50 via the refrigerant outlet 60 to be re-heated and vaporized in another part of the refrigerant circuit.

[0020] It is to be appreciated by a person of skill with the benefit of this description that the compartment 62 and the compartment 72 are not limited and may include more compartments or sub-compartments that can be added to form alternating layers of refrigerant flow and fluid flow to increase thermal contact between the compartment 62 and the compartment 72. In other examples, the compartment 62 and the compartment 72 may form a shell and tube-type condenser. In further examples, the compartment 62 and the compartment 72 may also be configured to follow a tortuous route and may be provided with internal fins, baffles, or protrusions to increase heat transfer efficiency.

[0021] In the present example, the heat exchanger 65 is constructed from materials which can separate the refrigerant in the compartment 62 from the fluid in the compartment 72 while providing high thermal conductivity between the compartment 62 to the compartment 72. The fluid flowing into and through the compartment 72 is not particularly limited. In the present example, the fluid flowing into and through the compartment 72 is air. In other examples, the fluid may be a liquid, such as water or other fluid with a high heat capacity. Some examples of suitable materials to separate the compartment 62 from the compartment 72 include copper, stainless steel, aluminum, and other similar materials. The exact configuration of the compartment 62 and the compartment 72 is not particularly limited. In the present example, the compartment 62 and the compartment 72 are configured such that the refrigerant in the compartment 62 and the fluid in the compartment 72 flow in opposite directions. In other examples, the configuration of the compartment 62 and the compartment 72 can be configured such that the refrigerant and the water flow in the same direction; however it is to be appreciated by a person of skill with the benefit of this description that the locations of the fluid inlet 70, the fluid outlet 75, and the fluid outlet 80 may be adjusted accordingly.

[0022] The fluid inlet 70 is to receive a fluid from a source. In the present example, the fluid inlet 70 is to receive air from a return duct. It is to be appreciated by a person of skill with the benefit of this description that the air may be received from an opening or from a source outside of a building. In further examples, the fluid received at the fluid inlet 70 may be a liquid, such as water. In the present example, the fluid, such as air, is received proximate to the cold portion 69 of the heat exchanger 65. The fluid flows through a compartment 72 to one of the fluid outlet 75 or the fluid outlet 80 where the fluid leaves the compartment 72. The fluid, such as air, in the compartment 72 is separated from the compartment 62 by the heat exchanger 65 such that the fluid does not mix with the refrigerant. As the fluid travels through the compartment 72 from the fluid inlet 70 to one of the fluid outlet 75 or the fluid outlet 80, the fluid absorbs heat from the refrigerant that is transferred via the heat exchanger 65. It is to be appreciated by a person of skill with the benefit of this description that the fluid will gradually increase in temperature as it travels from the cold portion 69 to the warm portion 68, and subsequently to the hot portion 67 while absorbing heat from the refrigerant through the heat exchanger 65.

[0023] The fluid outlet 75 and the fluid outlet 80 are to provide exit ports for the fluid flowing through the compartment 72 from the fluid inlet 70. The manner by which the fluid is divided between the fluid outlet 75 and the fluid outlet 80 is not particularly limited. For example, the size of each of the fluid outlet 75 and the fluid outlet 80 may be designed to provide different amounts of fluid, such as air, exiting from each of the fluid outlet 75 and the fluid outlet 80. In the present example, the fluid outlet 75 is disposed proximate to the warm portion 68 of the heat exchanger 65. The fluid outlet 80 is disposed proximate to the hot portion via the fluid outlet 75 is at a lower temperature than the fluid exiting the compartment 72 via the fluid outlet 80.

[0024] It is to be appreciated by a person of skill in the art with the benefit of this description that the apparatus 50 may be varied to accommodate a specific application. For example, modifications may be made to adjust the ratio of fluid leaving the fluid outlet 75 to fluid leaving the fluid outlet 80. The manner by which the ratios are adjusted and/or controlled is not particularly limited. For example, the ratio may be set by designing the fluid outlet 75 and the fluid outlet 80 to have a predetermined cross section such that fluid flow dynamics can determine the ratio of fluid leaving the fluid outlet 75 to fluid leaving the fluid outlet 80. By adjusting this ratio, the relative temperatures of the fluid, such as air, leaving the fluid outlet 75 and the fluid outlet 80 can be set. In this specific example, it is to be understood that the temperature of the air leaving the fluid outlet 75 and the fluid outlet 80 is also dependent on the manner and rate at which heat energy is transferred from the refrigerant in the compartment 62 to the air in the compartment 72. The rate at which heat energy is transferred is not particularly limited and can depend on several factors such as the material, size, and geometry of the heat exchanger 65, as well as the characteristics of the refrigerant.

[0025] In a specific application, the apparatus 50 may be designed to supply warm air from the fluid outlet 75 for space heating applications. The temperature of the air supplied from the fluid outlet 75 for such an application is not particularly limited. For example, the air supplied from the fluid outlet 75 may be about 30 degrees Celsius. In other examples, the air supplied from the fluid outlet 75 may be higher or lower than this temperature. Continuing with this example, the fluid outlet 80 may be designed to supply hot air for various applications. The application using the hot air is not limited and may include providing the hot air to a clothes dryer or other appliance that uses hot air, such as a convection oven. In the example of supplying hot air to a clothes dryer, the temperature of the air supplied from the fluid outlet 80 may be about 50 degrees Celsius. In other examples, the air supplied from the fluid outlet 80 may be higher or lower than this temperature. For example, for applications where the fluid outlet 80 is to supply air to a convection oven, the temperature of the air supplied from the fluid outlet 80 may be about 200 degrees Celsius.

[0026] Referring to figure 2, another example of an apparatus 50a to supply heat via multiple outputs at different temperatures is generally shown. Like components of the apparatus 50a bear like reference to their counterparts in the apparatus 50, except followed by the suffix “a”. In the present example, the apparatus 50a includes refrigerant inlet 55a, a refrigerant outlet 60a, a heat exchanger 65a, a fluid inlet 70a, a fluid outlet 75a, and another fluid outlet 80a. The refrigerant side of the apparatus 50a functions in a substantially similar manner as that in the apparatus 50. In the present example, the refrigerant is received at the refrigerant inlet 55a in the form of a vapor. The refrigerant flows through a compartment 62a that is sealed from the external environment to the refrigerant outlet 60a where the refrigerant leaves the compartment 62a in the form of a liquid. As the refrigerant travels through the compartment 62a, the refrigerant gives off heat that is transferred to the compartment 72a via the heat exchanger 65a.

[0027] In the present example, the apparatus 50a further includes a damper system to control the flow of fluid, such as air, through the compartment 72a to the fluid outlet 75a and the fluid outlet 80a. In the present example, the damper system includes a damper 77a disposed in the fluid outlet 75a and a damper 82a disposed in the fluid outlet 80a. The damper 77a is not particularly limited and may be any type of damper or valve capable of restricting the flow or fluid, such as air, through the fluid outlet 75a. For example, the damper 77a may include a rotatable plate, such as a butterfly valve, to regulate the air flow through the fluid outlet 75a. In other examples, the damper 77a may include a plurality of rotatable blades to regulate the air flow through the fluid outlet 75a. In further examples, the damper 77a may be another type of valve. It is to be appreciated by a person of skill with the benefit of this description that that damper 82a may be similar to the damper 77a or may be another type of damper.

[0028] In the present example, the damper 77a and the damper 82a are to be independently controlled. The manner by which the damper 77a and the damper 82a are controlled is not particularly limited. For example, the damper 77a and the damper 82a may be manually controlled via mechanical means such as by operating a knob, wheel, or lever to move the damper 77a between an open position and a closed position as well as any other position therebetween to reduce the amount of airflow but not to cut off the airflow through the fluid outlet 75a. In other examples, the damper 77a and the damper 82a may be automatically controlled and operated by a motor receiving commands or signals from an external device.

[0029] By adjusting the flow through each of the fluid outlet 75a and the fluid outlet 80a, the ratio of fluid leaving the compartment 72a via the fluid outlet 75a and the fluid outlet 80a may be adjusted. For example, closing or reducing fluid flow through the fluid outlet 80a will increase the fluid flow out of the fluid outlet 75a. Therefore, more warm air may be directed to the application associated with the fluid outlet 75a. It is to be appreciated by a person of skill with the benefit of this description that by adjusting the ratios of fluid leaving the compartment 72a via the fluid outlet 75a and the fluid outlet 80a, the apparatus 50a may be able to meet changing demands for heat supply. Referring again to the example application above where the apparatus 50a is to be designed to supply warm air from the fluid outlet 75a for space heating applications and to supply hot air from the fluid outlet 80a for a clothes dryer, the damper 82a may be opened when the clothes dryer is in operation and closed when the clothes dryer is not in operation. By closing the damper 82a when the clothes dryer is not in operation, wastage of heat supplied via the fluid outlet 80a is reduced as most of the air may leave the compartment 72a via the fluid outlet 75a.

[0030] It is to be appreciated that variations to the damper system are contemplated. For example, one of the damper 77a and the damper 82a may be omitted such that the ratio of fluid flowing through the fluid outlet 75a and the fluid outlet 80a may be adjusted by restricting air through one of the fluid outlet 75a and the fluid outlet 80a. In this example, the damper 77a may be omitted from the apparatus 50a such that the fluid leaving through the fluid outlet 75a is not regulated. When hot air from the fluid outlet 80a is used, the damper 82a may be opened to a target setting. As airflows out through the fluid outlet 80a, less air flows through the fluid outlet 75a. Once the application associated with the fluid outlet 80a is stopped, the damper 82a may be closed to provide more air via the fluid outlet 75a. As another example of a variation, the damper 82a may be omitted from the apparatus 50a such that the damper 77a is to control the amount of fluid flowing via the fluid outlet 80a.

[0031] In the present example, both of the damper 77a and the damper 82a may be used to control the temperature of the fluid leaving the compartment via the fluid outlet 75a and the fluid outlet 80a. For example, the damper 77a and the damper 82a may both be set to restrict fluid flow such that the fluid remains within the compartment 72a for a longer period of time as it travels from the fluid inlet 70a to the fluid outlet 75a and the fluid outlet 80a. By remaining in the compartment 72a for a longer period of time, the fluid will absorb more heat from the heat exchanger 65a. Accordingly, the fluid may then be used for applications that use higher temperatures.

[0032] The present example further includes a fan 73a to move fluid, such as air from the fluid inlet 70a through the compartment 72a to the fluid outlet 75a and the fluid outlet 80a. The manner by which the fan 73a operates is not particularly limited and the fan 73a may be any type of fan capable of moving fluid, such as air, through the apparatus 50a. In other examples, the fan 73a may also be substituted with a pump to move the fluid. The exact position of the fan 73a is also not particularly limited and some examples may place the fan 73a in the compartment 72a. In other examples, one or more fans may be disposed in the fluid outlet 75a and the fluid outlet 80a.

[0033] Referring to figure 3, another example of an apparatus 50b to supply heat via multiple outputs at different temperatures is generally shown. Like components of the apparatus 50b bear like reference to their counterparts in the apparatus 50a, except followed by the suffix “b”. In the present example, the apparatus 50b includes refrigerant inlet 55b, a refrigerant outlet 60b, a heat exchanger 65b, a fluid inlet 70b, a fan 73b, a fluid outlet 75b, and another fluid outlet 80b. The refrigerant side of the apparatus 50b functions in a substantially similar manner as that in the apparatus 50a. In the present example, the refrigerant is received at the refrigerant inlet 55b in the form of a vapor. The refrigerant flows through a compartment 62b separated from the external environment to the refrigerant outlet 60b where the refrigerant leaves the compartment 62b in the form of a liquid. As the refrigerant travels through the compartment 62b, the refrigerant gives off heat that is transferred to the compartment 72b via the heat exchanger 65b.

[0034] In the present example, the apparatus 50b provides a heat supply to an application 200, such as space heating, at a lower temperature via the fluid outlet 75b. In addition, the apparatus 50b provides a heat supply to an application 210, such as a clothes dryer, at a higher temperature via the fluid outlet 80b.

[0035] The damper 77b provides control to the ratio of fluid that is to flow through the fluid outlet 75b and the fluid outlet 80b. The apparatus also includes a valve 74b to control the fluid flow to the application 200 and the application 210. The valve 74b is not particularly limited and may be omitted in some examples. In the present example, the valve 74b may be a check valve to control the direction of flow. In this example, the valve 74b may be used to allow excess hot air from the fluid outlet 80b to be used in the application 200 to avoid wasted heat while preventing the warm air from the fluid outlet 75b to mix with the hot air used by the application 210. In other examples, the valve 74b may be a gate valve or damper, such as a ball valve or butterfly valve, to separate or control the flow of fluid.

[0036] In operation, the damper 77b may be opened when there is less demand for heat from the application 210 so that more fluid can be directed through the fluid outlet 75b to the application 200. In this state, it is to be appreciated that less fluid may flow through the fluid outlet 80b as more fluid will flow through the fluid outlet 75b. In the present example, if the application 210 does not allow any fluid or heat to pass through, the pressure from the fluid outlet 80b will force fluid through the valve 74b to the application 200. Alternatively, when the demand for heat from the application 210 is high, the damper 77b may be closed to direct substantially all of the fluid through the fluid outlet 80b. [0037] In the present example, the apparatus 50b may further include an air exchanger 85b to re-capture heat from the application 210. The heat may be added to air received from an air intake 220 prior to reaching the fluid inlet 70b. It is to be appreciated by a person of skill that by adding heat to the air from the air intake 220, less energy may be used to heat the air to the same temperature at the fluid outlet 75b and the fluid outlet 80b.

[0038] The air exchanger 85b is not particularly limited. In the present example, the air exchanger 85b includes separate channels made from a thermally conductive material, such as metal, passing through the path of fluid received from the air intake 220. The channels allow waste fluid from the application 210 to pass therethrough, which thermally conducts heat to the fluid received from the air intake 220. Accordingly, the air exchanger 85b separates the fluids from the application 210 and the air intake 220 to prevent mixing. Once the heat is transferred from the waste fluid to air from the air intake, the waste fluid is expelled via an exhaust 230. The exhaust 230 is not particularly limited and may be disposed outside of a building such that the waste fluid along with any other contaminants from the application 210 leaving is expelled to the outside environment. Continuing with the example where the application 200 is space heating and the application 210 is a clothes dryer, it is to be appreciated by a person of skill with the benefit of this description that the exhaust of the dryer generally includes high moisture content as well as excess heat above the ambient temperature. The air exchanger 85b allows the heat to be recaptured to an extent without re-circulating the moist air into the application 200.

[0039] Referring to figure 4, another example of an apparatus 50c to supply heat via multiple outputs at different temperatures is generally shown. Like components of the apparatus 50c bear like reference to their counterparts in the apparatus 50b, except followed by the suffix “c”. In the present example, the apparatus 50c includes refrigerant inlet 55c, a refrigerant outlet 60c, a heat exchanger 65c, a fluid inlet 70c, a fan 73c, a fluid outlet 75c with a damper 77c, and another fluid outlet 80c. In the present example, the refrigerant is received at the refrigerant inlet 55c in the form of a vapor. The refrigerant flows through a compartment 62c separated from the external environment to the refrigerant outlet 60c where the refrigerant leaves the compartment 62c in the form of a liquid. As the refrigerant travels through the compartment 62c, the refrigerant gives off heat that is transferred to the compartment 72c via the heat exchanger 65c.

[0040] In the present example, the apparatus includes an additional valve 83c to control the fluid flow to the application 200 and the application 210 in combination with the damper 77c. In particular, the valve 83c may operate to allow fluid to flow to the application 210 or to close the path to the application 210 and direct the fluid to the application 200. The valve 83c may be a damper type valve, such as a ball valve or a butterfly valve, to control the amount of air flowing therethrough. Therefore, the damper 77c and the valve 83c may be controlled in combination to vary the proportion of fluid flow between the appliance 200 and the appliance 210. In other examples, the valve 83c may be a gate valve to turn on or off a flow of fluid. In other examples, the valve 83c may be a damper, such as a ball valve or butterfly valve, to control the flow to the application 210, which also controls the flow to the application 200.

[0041] Referring to figure 5, another example of an apparatus 50d to supply heat via multiple outputs at different temperatures is generally shown. Like components of the apparatus 50d bear like reference to their counterparts in the apparatus 50b, except followed by the suffix “d”. In the present example, the apparatus 50d includes refrigerant inlet 55d, a refrigerant outlet 60d, a heat exchanger 65d, a fluid inlet 70d, a fan 73d, a fluid outlet 75d with a damper 77d, and another fluid outlet 80d. In the present example, the refrigerant is received at the refrigerant inlet 55d in the form of a vapor. The refrigerant flows through a compartment 62d separated from the external environment to the refrigerant outlet 60d where the refrigerant leaves the compartment 62d in the form of a liquid. As the refrigerant travels through the compartment 62d, the refrigerant gives off heat that is transferred to the compartment 72d via the heat exchanger 65d.

[0042] In the present example, the apparatus includes an additional valve 83d that operates in combination with the valve 74d to control the fluid flow to the application 200 and the application 210. In particular, the valve 83d may operate to allow fluid to flow to the application 210 or to close the path to the application 210 and direct the fluid to the application 200. Accordingly, it is to be appreciated by a person of skill with the benefit of this description that at least one of the valve 74d and the valve 83d are to be in an open position during operation. In the present example, the valve 83d may be a gate valve to turn on or off a flow of fluid. In other examples, the valve 83d may be a damper, such as a ball valve or butterfly valve, to control the flow to the application 210, which can also control the flow to the application 200.

[0043] In the example where the application 210 is a clothes dryer, the exhaust from the application 210 may be a fluid, such as warm moist air, that is expelled through an exhaust 235. Accordingly, when the application 210 is in operation, the exhaust 235 may direct warm moist air to a location in the building to provide space heating as well as humidification. Furthermore, in some examples, an optional air treatment unit 81 d may be disposed between the application 210 and the exhaust 235 to clean the air leaving the exhaust 235. For example, the air treatment unit 81 d may be a filter to remove particulate material or lint from the application 210 if it is a clothes dryer. In other examples, the air treatment unit 81 d may be an air freshener or carbon filter to remove odors from the air leaving the exhaust 235.

[0044] Referring to figure 6, another example of an apparatus 50e to supply heat via multiple outputs at different temperatures is generally shown. Like components of the apparatus 50e bear like reference to their counterparts in the apparatus 50, except followed by the suffix “e”. In the present example, the apparatus 50e includes refrigerant inlet 55e, a refrigerant outlet 60e, a heat exchangers 65e-1, 65e-2 (generically, these heat exchangers are referred to herein as “heat exchanger 65e” and collectively they are referred to as “heat exchangers 65e”), a fluid inlet 70e-1, a fluid outlet 75e, and another fluid outlet 80e.

[0045] In the present example, the refrigerant is received at the refrigerant inlet 55e in the form of a vapor. The refrigerant flows through a compartment 62e-1 to release heat energy and transferred to another compartment 62e-2 via a connector 57e to release more heat energy. The refrigerant then leaves the compartment 62e-2 in the form of a liquid via the refrigerant outlet 60e. As the refrigerant travels through the compartments 62e-1 , 62e-2, the refrigerant gives off heat that is transferred to compartments 72e-1, 72e-2, respectively, via the heat exchangers 65e.

[0046] In the present example, the apparatus 50e includes two heat suppliers 52e-1 , 52e-2. The heat supplier 52e-1 provides heat at a high temperature as heat is transferred from the hot refrigerant vapor in the compartment 62e-1 to the fluid flowing through the compartment 72e-1. The heat supplier 52e-2 provides heat at a warm temperature as heat is transferred from the refrigerant in the compartment 62e-2 to the fluid flowing through the compartment 72e-2. It is to be appreciated by a person of skill with the benefit of this description that the design of the apparatus 50e, such as the relative size of the compartment 62e-1 to the compartment 62e-2, is not particularly limited. In the present example, the heat supplier 52e-1 may be a condenser to condense the vapor refrigerant to a liquid from when the refrigerant reaches the connector 57e. Accordingly, the heat supplier 52e-2 may be a sub-cooler in this example as it further reduces the temperature of the refrigerant in the compartment 62e-2 by transferring heat to the fluid in the compartment 72e-2. In this example, the warm portion described above may be physically separated such that the heat supplier 52e-2 functions as the warm portion and the heat supplier 52e-1 functions as the hot portion. In other examples, it is to be appreciated that the heat supplier 52e-1 may not fully condense the refrigerant such that a mixture of liquid and vapor or a vapor flows through the connector 57e.

[0047] The fluid outlet 75e provides warm air for an application such as space heating. In the present example, a portion of the warm air is directed to the fluid inlet 70e-2 of the heat supplier 52e-1. It is to be appreciated by a person of skill with the benefit of this description that by providing warm air to the fluid inlet 70e-2 allow for the fluid supplier at the fluid outlet 80e to reach a higher temperature than if ambient air were to be received at the fluid inlet 70e- 2. However, in some variations, the fluid inlet 70e-2 may receive air from the atmosphere similar to the fluid inlet 70e-1 to avoid the additional connections to direct the air from the fluid outlet 75e to the fluid inlet 70e-2.

[0048] Referring to figure 7, an energy curve diagram 700 describing the operation of the apparatus 50 is generally shown. The energy curve plots the temperature of the refrigerant or fluid (see legend) against the amount of heat transferred over an arbitrary period of time. It is to be appreciated by a person of skill with the benefit of this description that the energy curve is just one example and that the curve may be dependent on various factors, such as the design of the apparatus 50 as well as the compressor and other components of the refrigerant path. In addition, the fluid flow through the compartment 72, such as due to the power of a propeller or fan, may affect the energy curve as well.

[0049] In the present example, the refrigerant enters the compartment 62 via the refrigerant inlet 55 at the point 705 of the energy curve. At the point 705, the refrigerant is a vapor and at a high temperature to raise the temperature of the fluid in the hot portion 67 via the heat exchanger. As the refrigerant moves toward the warm portion 68, the vapor transfers heat and decreases in temperature until point 710 where refrigerant begins to condense and lose latent heat to point 715. While the refrigerant loses latent heat, the temperature of the refrigerant does not substantially change. It is to be appreciated that in some examples where a mixture of refrigerants are used, the temperature may glide between the boiling points of the refrigerants. After the refrigerant substantially condenses to a liquid, the liquid continues to shed heat from the point 715 to the point 720 in the cold portion 69 until the refrigerant leaves the compartment via the refrigerant outlet 60 at point 720.

[0050] On the fluid side in the compartment 72, the fluid enters the compartment 72 via the fluid inlet 70 at a low temperature at point 725 of the energy curve. The fluid continues to receive heat through the cold portion 69 and the warm portion 68 from the refrigerant through the heat exchanger 65. Since the fluid in the compartment does not go through a phase change, the temperature steadily increases until point 730 where some mass leaves the compartment 72 through the fluid outlet 75. The rate of temperature increase may speed up as there is less mass remaining in the compartment 72 through the hot portion 67 until the remaining fluid leaves the compartment 72 through the fluid outlet 80.

[0051] Referring to figure 8, a system 100 to supply heat via multiple outputs at different temperatures using a heat pump is generally shown. It is to be appreciated by a person of skill with the benefit of this description that the system 100 may include variants with additional features and take different forms. In the present example, the system 100 includes a refrigerant circuit 105 with an expansion valve 107, an evaporator 110, a compressor 115, and a heat exchange system 150.

[0052] In the present example, the refrigerant circuit 105 is a circuit to circulate the refrigerant through the different components of the system 100. The refrigerant circuit 105 is a closed circuit such that the amount of refrigerant is separated from other components and the environment such that no refrigerant leaves or enters the circuit.

[0053] The evaporator 110 is in thermal communication with an external heat source, such as a waste heat sink. The evaporator 110 is disposed on the refrigerant circuit 105 to add heat energy to the refrigerant in the refrigerant circuit 105 to heat the refrigerant. The heat is to transform the refrigerant from a liquid to a vapor. In some examples, the heat source will not be at a higher temperature than the ambient temperature such that the system pumps heat from a cooler atmosphere, such as the exterior of a building, to a warmer atmosphere.

[0054] Once in a vapor form, the refrigerant continues along the refrigerant circuit 105 to the compressor 115. In the present example, the compressor 115 receives the vapor from the refrigerant circuit 105 and compresses the vapor to a higher pressure. The high pressure refrigerant continues along the refrigerant circuit 105 to the heat exchange system 150 where heat from the refrigerant is absorbed and condensed to liquid refrigerant. The liquid refrigerant continues back to the evaporator 110 where the cycle continues.

[0055] The heat exchange system 150 includes a fluid intake 170 and heat supplies 175, 180. In the present example, the fluid intake 170 is to receive a fluid, such as air or water. The heat supply 175 is to provide fluid at a low temperature and the heat supply 180 is to provide fluid a higher temperature than that provided from the heat supply 175.

[0056] The manner by which the heat exchange system 150 operates is not particularly limited. In general, the heat exchange system 150 receives fluid, such as air or water, at a low temperature. The heat exchange system 150 transfers heat from the refrigerant circuit 105 to the fluid received at the fluid intake 170 and releases the heated fluid through the heat supplies 175, 180. In the present example, the heat exchange system 150 may be any one of the apparatus 50, 50a, 50b, 50c, 50d, or 50e described above.

[0057] Referring to figure 9, a flowchart of a method of supplying heat via multiple outputs at different temperatures is generally shown at 500. In order to assist in the explanation of method 500, it will be assumed that method 500 may be one exemplary way by which the apparatus 50 or its variants may be used. Furthermore, the following discussion of method 500 may lead to a further understanding of the apparatus 50 and the system 100. In addition, it is to be emphasized, that method 500 may not be performed in the exact sequence as shown, and various blocks may be performed in parallel rather than in sequence, or in a different sequence altogether.

[0058] Beginning at block 510, the refrigerant is received into the compartment 62 as a vapor. The manner by which the refrigerant is received is not particularly limited. For example, the apparatus 50 may be part of a refrigerant cycle where the refrigerant is cycled through a circuit and received at the apparatus 50 via the refrigerant inlet 55.

[0059] Block 520 comprises receiving air or another fluid via the fluid inlet 70. In the present example, the air is received into the compartment 72. Although physically separated such that the refrigerant in the compartment 62 does not mix with the air in the compartment 72, the refrigerant and air are in thermal contact via the heat exchanger 65. It is to be appreciated that in the present example, the refrigerant in the compartment 62 and the fluid in compartment 72 flow in opposite directions. Referring to figure 1, the refrigerant flows from the top of the compartment 62 to the bottom of the compartment 62 where the refrigerant is released via the refrigerant outlet 60. By contrast, the fluid in the compartment 72 flows from the bottom to the top. As the refrigerant and the fluid flow pass each other, the fluid increases in temperature whereas the refrigerant decreases in temperature.

[0060] Accordingly, at block 530 heat is to be removed from the refrigerant. In the present example, the heat is removed via thermal conduction from the refrigerant to the fluid. The rate at which the heat is removed is not particularly limited and is generally carried out at the full flow rate of the heat exchanger 65. In the present example, the refrigerant is condensed from a vapor to a liquid in the compartment 62. Accordingly, different stages of heat removal may occur where the heat is to be transferred to the fluid in the compartment 72. First, the heat may be removed from the vapor refrigerant (referred to as the superheat of the refrigerant) to decrease the temperature of the refrigerant in the hot portion 67 of the heat exchanger 65. Upon reaching the boiling point for the refrigerant under the conditions in the compartment 62, a liquid-vapor mixture is formed. Next, heat (referred to as the latent heat of the refrigerant) may continue to be removed from the liquid-vapor mixture in the warm portion 68 of the heat exchanger 65. It is to be appreciated by a person of skill that in the warm portion 68, the removal of heat from the refrigerant by the heat exchanger 65 does not substantially change the temperature of the refrigerant. Accordingly, the warm portion 68 of the heat exchanger 65 is substantially at the same temperature. It is to be appreciated that if a mixture of refrigerants is used, the temperature may glide through the warm portion 68. After completely condensing, heat from the refrigerant will then continue to be removed from the liquid in the cold portion 69 of the heat exchanger 65 via supercooling.

[0061] Next, block 540 supplies a portion of the air at a low temperature via the fluid outlet 75. The manner by which the temperature of the air is increased from the ambient temperature when received at the fluid inlet 70 is not particularly limited. In the present example, the air received at block 520 is passed through the warm portion 68 and the cold portion 69 of the heat exchanger 65 to the fluid outlet 75. By being in thermal contact with the heat exchanger 65, the air absorbs the heat provided from the refrigerant. [0062] Block 550 supplies a portion of the air at a different temperature via the fluid outlet 80. In the present example, the temperature of the air provided from the fluid outlet 80 is higher than the air provided by the fluid outlet 75. After passing through the warm portion 68 of the heat exchanger 65, a portion of the air received at block 520 is released via the fluid outlet 75 and the remaining air proceeds to pass through the hot portion 67 of the heat exchanger 65 to absorb more heat from the refrigerant as it releases heat from the vapor form.

[0063] It is to be appreciated by a person of skill with the benefit of this description that variations to the method 500 are possible. For example, the method 500 may include additional steps to control the air supplied in block 540 and block 550. For example, the ratio of the portions of air being supplied by block 540 and block 550 may be controlled. The manner of control is not limited and may include a damper system, such as the one described in connection with the apparatus 50a.

[0064] It should be recognized that features and aspects of the various examples provided above may be combined into further examples that also fall within the scope of the present disclosure.