HYBRID TOP/SIDE DISCHARGE HEAT PUMP WITH NON-STOP HEATING UNDER FROSTING CONDITION

BACKGROUND

[0001]This disclosure relates, in general, to a heat pump system and, not by way of limitation, to providing continuous heating through the heating system, among other things.

[0002]A heat pump is an electrical device that transfers heat from one place to another. An outdoor unit of the heat pump acts as a condenser during a cooling mode and as an evaporator during a heating mode. During both the heating mode and the cooling mode, a heat exchanger facilitates heat exchange between a refrigerant and airflow.

[0003]Frost occurs when outdoor temperature is low and humidity is high, causing frost to form on the outdoor unit of the heat pump. Frost formation reduces the efficiency of the heat pump by covering outdoor unit coils and impeding heat transfer.

SUMMARY

[0004]In one embodiment, the present disclosure provides a hybrid heat pump system with an indoor unit and a hybrid top/side discharge outdoor unit for continuous heating under a defrosting mode. The outdoor unit contains a heat exchanger and a compressor. The outdoor unit is divided into an upper compartment and a lower compartment. The upper compartment is further divided into a right portion and a left portion. Two bi-directional fans are installed at a boundary of the upper compartment and the lower compartment, one in each portion. The outdoor unit operates under different modes. During the defrosting mode, the bi-directional fans push air in opposite directions, and airflow due to the bi-directional fans bypasses the compressor in the lower compartment of the outdoor unit.

[0005]In an embodiment, a heat pump system with an indoor unit and a hybrid top/side discharge outdoor unit for continuous heating under a defrosting mode. The outdoor unit contains a heat exchanger and a compressor. The outdoor unit is divided into an upper compartment and a lower compartment. The upper compartment is further divided into a right portion and a left portion. Two bi-directional fans are installed at a boundary of the upper compartment and the lower compartment, one in each portion. A first fan is installed at the boundary of the lower compartment and the left portion of the upper compartment. A second fan is installed at the boundary of the lower compartment and the right portion of the upper compartment. The outdoor unit operates under different modes. During the defrosting mode, the bi-directional fans push air in opposite directions. As a result, the first fan pushes air downwards and the second fan pushes air upwards. Furthermore, airflow due to the bi-directional fans bypasses the compressor in the lower compartment of the outdoor unit during the defrosting mode.

[0006]In another embodiment, a hybrid heating method for an indoor unit and an outdoor unit with continuous heating under a defrosting mode. The outdoor unit contains a heat exchanger and a compressor. In one step, the hybrid heating method includes dividing the outdoor unit into an upper compartment and a lower compartment. The hybrid heating method further includes dividing the upper compartment into a right portion and a left portion and positions the compressor in the lower compartment. Two bi-directional fans are installed at a boundary of the upper compartment and the lower compartment, one in each portion. The hybrid heating method further includes installing a first fan at the boundary of the lower compartment and the left portion of the upper compartment, and a second fan at the boundary of the lower compartment and the right portion of the upper compartment. The hybrid heating method then includes determining a mode of operation for the outdoor unit. During the defrosting mode, the bi-directional fans push air in opposite directions. As a result, the first fan pushes air downwards and the second fan pushes air upwards. Furthermore, airflow due to the bi-directional fans bypasses the compressor in the lower compartment of the outdoor unit during the defrosting mode.

[0007]In yet another embodiment, a heat pump system with an indoor unit and a hybrid top/side discharge outdoor unit for continuous heating under a defrosting mode. The outdoor unit contains a heat exchanger and a compressor. The hybrid heating system divides the outdoor unit into an upper compartment and a lower compartment. The hybrid heating system further divides the upper compartment into a right portion and a left portion and positions the compressor in the lower compartment. Two bi-directional fans are installed at a boundary of the upper compartment and the lower compartment, one in each portion. The hybrid heating system further installs a first fan at the boundary of the lower compartment and the left portion of the upper compartment, and a second fan at the boundary of the lower compartment and the right portion of the upper compartment. The hybrid heating system then determines a mode of operation for the outdoor unit. During the defrosting mode, the bi-directional fans push air in opposite directions. As a result, the first fan pushes air downwards and the second fan pushes air upwards. Furthermore, airflow due to the bi-directional fans bypasses the compressor in the lower compartment of the outdoor unit during the defrosting mode.

[0008]Further areas of applicability of the present disclosure will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating various embodiments, are intended for purposes of illustration only and are not intended to necessarily limit the scope of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]The present disclosure is described in conjunction with the appended figures:

[0010]FIG. 1 illustrates an outdoor unit of a hybrid top/side discharge heat pump system with continuous heating;

[0011]FIGS. 2A-2B illustrate a conventional heat pump under cooling and heating mode respectively.

[0012]FIG. 3 illustrates a refrigerant cycle diagram of the conventional heat pump system;

[0013]FIGS. 4A-4D illustrate the hybrid top/side discharge outdoor unit under different modes;

[0014]FIGS. 5A-5D illustrate cycle diagrams of the heat pump of the hybrid top/side discharge outdoor unit under different modes; and

[0015]FIG. 6 illustrates a hybrid heating method under different modes, with continuous heating in defrosting mode.

[0016]In the appended figures, similar components and/or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.

DETAILED DESCRIPTION

[0017]The ensuing description provides preferred exemplary embodiment(s) only, and is not intended to limit the scope, applicability, or configuration of the disclosure. Rather, the ensuing description of the preferred exemplary embodiment(s) will provide those skilled in the art with an enabling description for implementing a preferred exemplary embodiment. It is understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope as set forth in the appended claims.

[0018]Referring to FIG. 1, a hybrid top/side discharge outdoor unit 102 of a hybrid heating system 100 with continuous heating under a frosting condition is shown. During adverse weather conditions, the frosting of the hybrid top/side discharge outdoor unit 102 in a heat pump system is a common issue. This problem often arises due to factors such as low refrigerant levels, poor airflow, or malfunctioning defrost cycles. As an alternative to manually defrosting the hybrid top/side discharge outdoor unit 102 by running warm or hot refrigerant over portion of coils of the hybrid top/side discharge outdoor unit 102, the hybrid heating system 100 provides continuous defrosting mode to keep the heat pump operating smoothly. Thus, the hybrid heating system 100 is operable as a hybrid top/side discharge heat pump with non-stop heating under frosting conditions with multiple modes, i.e., heating, cooling, booster heating, and defrosting mode.

[0019]The hybrid heat pump system 100 includes a house 103, a heat pump, an indoor unit 110, and an hybrid top/side discharge outdoor unit 102. The hybrid heat pump system 100 provides hybrid heating for the house 103. The outdoor temperature and humidity levels play a major role in determining the efficiency of the heat pump.

[0020]The hybrid top/side discharge outdoor unit 102 has two compartments: an upper compartment 104 and a lower compartment 106. The upper compartment 104 and the lower compartment 106 both have heat exchangers. The heat exchangers in both upper and lower compartments 104 and 106 can have similar or different designs based on the specifications of the hybrid heat pump system 100. Hybrid top/side discharge outdoor unit 102 has a fan at the top of the upper compartment 104. The hybrid top/side discharge outdoor unit 102 further houses a compressor in the lower compartment 106, and a condenser coil at the bottom devoid of venting. The compressor increases the pressure and temperature of a refrigerant, which then flows through the condenser coil. Here, heat from the refrigerant is released into surrounding air, aided by the fan, which blows air over the condenser coil to enhance the cooling process. This cycle maintains a desired indoor temperature and ensures the efficiency of an air conditioning system in any mode i.e., heating, cooling, booster heating, and/or defrosting mode. In one example, hybrid top/side discharge outdoor unit 102 has solar panels 108 installed on sides and top of the hybrid top/side discharge outdoor unit 102 to harvest solar energy.

[0021]Referring next to FIG. 2A, a unit 200-1 of hybrid heat pump system 100 with conventional heat pump design under cooling mode is shown. The unit 200-1 includes an indoor coil 202, an outdoor coil 204, a compressor 206, a reversing valve 208, an indoor fan 210, and an outdoor fan 212. The unit 200-1 further includes a filter-drier 222, an indoor melting device 214, an outdoor melting device 216, an indoor check valve 218, and an outdoor check valve 220. Compressor 206 compresses the refrigerant, increasing the pressure and temperature of the refrigerant. In cooling mode, the reversing valve 208 directs the pressurized refrigerant to the outdoor coil 204. At the outdoor coil 204, the refrigerant releases heat to the outside air, cooling down, and condenses into a liquid. The filter-drier 222 removes impurities and moisture from the refrigerant to protect the hybrid heat pump system 100. The indoor melting device 214 regulates a flow of the refrigerant into the indoor coil 202, ensuring the right amount of the refrigerant enters the indoor coil 202. At indoor coil 202, the refrigerant absorbs heat from indoor air, cooling the indoor air down before returning to the compressor 206 to repeat the cycle.

[0022]When in cooling mode, the unit 200-1 operates on the principle of heat transfer, effectively working as an air conditioner. The unit 200-1 uses a refrigerant to absorb heat from inside a building and expels the absorbed heat outside, thus cooling the indoor environment of the building. The cooling process begins with the refrigerant in a low-pressure, gaseous state entering compressor 206, where the refrigerant is compressed to turn into a high-pressure, high-temperature gas. This gas then flows through the condenser coil, where the gas releases heat to the outside air, and while cooling down, the gas transforms into a liquid refrigerant.

[0023]This liquid refrigerant passes through an expansion valve, which reduces the pressure of the liquid refrigerant, to further cool down the liquid refrigerant. Now, the refrigerant enters the evaporator coils in a low-pressure, cold two-phase state. Here, the evaporator coils, and the refrigerant absorbs heat from the indoor air, causing it to evaporate and return to a gaseous state. The refrigerant, carrying the absorbed heat, is then cycled back to compressor 206 to repeat the cooling process.

[0024]While operating in the cooling mode, an indoor air handler blows air across the evaporator coils, facilitating a heat absorption process. Cooled air is then circulated back into the building, reducing indoor temperature. The reversing valve 208 allows the hybrid heat pump system 100 to switch between the heating and cooling modes. In cooling mode, the reversing valve 208 directs the refrigerant flow so that the heat is expelled outdoors.

[0025]Referring next to FIG. 2B, a unit 200-2 of the hybrid heat pump system 100 conventional heat pump design under heating mode is shown. The unit 200-2 under the heating mode has the same components as in the cooling mode, but the direction of airflow is now reversed. The unit 200-2 operates on the principle of heat transfer, which is the movement of heat from a warmer area to a cooler one. In the heating mode, the unit 200-2 reverses the flow of refrigerant to absorb heat from the outside air, even when the outside air is cold, and transfers the absorbed heat to the indoor air. A heating process begins with the refrigerant in the hybrid top/side discharge outdoor unit 102 absorbing heat from the outside air. The refrigerant, now carrying the absorbed heat, is compressed to a higher temperature and pressure, which increases the temperature of the refrigerant. The refrigerant is then circulated to indoor unit 110, where the refrigerant releases its absorbed heat into indoor space and indoor air.

[0026]Indoor fan 210 blows air across the indoor coil 202, transferring the heat to the air inside the house 103. As the refrigerant ejects its heat into the air flow, it turns back into a liquid. The liquid then returns to the hybrid top/side discharge outdoor unit 102, passing through an expansion valve that reduces the pressure and temperature of the liquid so that it is ready to absorb heat from the outdoor air once again.

[0027]The efficiency in the heating mode is measured by a coefficient of performance (COP) of the unit 200-2, which is a ratio of heat output to electrical energy input. A higher COP indicates a more efficient heat pump capable of providing more heat for a given amount of electrical energy.

[0028]Referring next to FIG. 3, a refrigerant cycle diagram 300 of conventional heat pump system is shown. Refrigeration is defined as the process of transferring heat from a low temperature region to a high temperature region. In other words, refrigeration is the process of cooling a substance. This is achieved when heat is removed from the substance. The refrigerant cycle diagram 300 includes the compressor 206, an indoor heat exchanger 316, and an outdoor heat exchanger 318. A 4-way valve 310 reverses the refrigerant flow to switch between the heating and cooling modes. Sensors 302-1, 302-2, 302-3, 302-4, 302-5, 302-6 monitor temperatures at various points in the cycle. A 2-way valve 308, and a 3-way valve 312 are used to switch between the liquid side and a gas side, respectively. Lined arrows show a heat flow in a heating mode, whereas dotted arrows show the heat flow in a cooling mode in the refrigerant cycle diagram 300.

[0029]During the cooling mode, indoor heat exchanger 316 acts as an evaporator and absorbs heat from the indoor environment, causing the refrigerant to evaporate. An electronic expansion valve (EEV) 320 reduces the pressure of the refrigerant before the refrigerant enters the evaporator. Compressor 206 increases the pressure and temperature of the refrigerant. The outdoor heat exchanger 318 acts as a condenser in the cooling mode. At the outdoor heat exchanger 318, the high-pressure refrigerant releases heat to an outdoor environment and condenses into a liquid.

[0030]During the heating mode, outdoor heat exchanger 318 acts as an evaporator to absorb heat from the outdoor environment, causing the refrigerant to evaporate. Compressor 206 increases the pressure and temperature of the refrigerant in the gaseous state. The indoor heat exchanger 316 acts as a condenser in the heating mode. The electronic expansion valve (EEV) 320 reduces the pressure of the refrigerant before it turns to enter the evaporator. At the indoor heat exchanger 316, the refrigerant releases heat to the indoor environment and condenses into a liquid.

[0031]Referring next to FIG. 4A, a heat exchanger of the hybrid top/side discharge outdoor unit 102 under a cooling mode 400-1 is shown. The hybrid top/side discharge outdoor unit 102 has solar panel 108 positioned on the top and main controls/drive boards 402 for system regulation. Hybrid top/side discharge outdoor unit 102 is divided into two compartments: an upper compartment 104 and a lower compartment 106. The upper compartment 104 is divided into two portions: a right portion 104-2 and a left portion 104-1. A set of bi-directional fans, including a first fan 404-1, and a second fan 404-2, is also installed in the hybrid top/side discharge outdoor unit 102 for altering the direction of airflow.

[0032]The first fan 404-1 is installed at the boundary in between the lower compartment 106 and the left portion 104-1 of the upper compartment 104. The second fan 404-2 is installed at the boundary in between the lower compartment 106 and the right portion 104-2 of the upper compartment 104. The upper compartment 104 has upper heat exchangers 414-1 on both sides and the lower compartment 106 has lower heat exchangers 414-2. Furthermore, compressor 206 is also positioned in lower compartment 106 of the hybrid top/side discharge outdoor unit 102. In the cooling mode 400-1, the heat exchanger dissipates heat to aid the cooling process. The refrigerant gas of the compressor raises the pressure and temperature of the refrigerant. The high-pressure refrigerant then flows through the condenser coil, where the heat is released to the surrounding air. A fan aids the cooling process by blowing air over the condenser coil, which helps to cool the refrigerant. This heat exchange allows the refrigerant to condense from a gaseous state to a liquid state, which is then cycled back to indoor unit 110 to absorb more heat from the interior space.

[0033]Referring next to FIG. 4B, a heat exchanger of the hybrid top/side discharge outdoor unit 102 under a normal heating mode 400-2 is shown. In the normal heating mode 400-2, the lower heat exchanger 414-2 of the hybrid top/side discharge outdoor unit 102 absorbs heat from the outdoor environment as an evaporator. Even in cold weather, heat energy is still present in the outside air, which the evaporator coil absorbs. The refrigerant within the evaporator coil then carries the absorbed heat after the compressor compression to indoor unit 110. Inside the house 103, condenser coils release the absorbed heat into the interior space, effectively heating the inside air.

[0034]The bi-directional fans now reverse airflow direction with respect to the cooling mode 400-1. Compressor 206 applies pressure and turns the refrigerant into a hot gas which is then supplied to the indoor unit 110. The upper heat exchanger 414-1 remains warm/unfrosted and rejects heat to the air flow, while the lower heat exchanger 414-2 will act as an evaporator and absorbs heat from the downstream air at the hybrid top/side discharge outdoor unit 102

[0035]Referring next to FIG. 4C, a heat exchangers of the hybrid top/side discharge outdoor unit 102 under a booster heating mode 400-3 is shown. The booster heating mode 400-3 allows the hybrid heat pump system 100 to produce more heat for comfort of a building in colder weather conditions. The airflow at the first fan 404-1 and the second fan 404-2 is same as in the normal heating mode i.e., both the first and second fans 404-1, 404-2 direct outside air downwards to the compressor 206. In the booster heating mode 400-3, both the upper heat exchanger 414-1 and the lower heat exchanger 414-2 of the outdoor unit will act as evaporators, effectively boosting the heating process. In colder weather (e.g. 5 F or below), the outdoor air holds less moisture, leading to less frost formation on the outdoor unit heat exchangers.

[0036]Referring next to FIG. 4D, a heat exchangers of the hybrid top/side discharge outdoor unit 102 with continuous heating under a defrosting mode 400-4 is shown. When temperatures drop below freezing, frost can accumulate on the outdoor coil, impeding the ability of the hybrid top/side discharge outdoor unit 102 to transfer heat effectively. The frost accumulation becomes worse when the outdoor air temperature is around 32 F, as the outdoor coil temperature drops below the freezing temperature and the outdoor air still holds a decent amount of moisture. To maintain efficiency and protect the system, the hybrid top/side discharge outdoor unit 102 periodically enters a defrosting mode 400-4. The defrosting mode 400-4 is controlled by the main controls/drive boards 402 within the hybrid top/side discharge outdoor unit 102, which can initiate the process based on a timer or sensors that detect ice buildup.

[0037]In traditional heat pump systems, while a defrost mode is active, the indoor heating may be suspended. During the defrost cycle, an outdoor fan typically stops, and the system reverses a refrigerant flow, temporarily switching to air conditioning mode to direct hot refrigerant through the condenser coil. This action melts the accumulated frost, and resulting water drains away, allowing the hybrid top/side discharge outdoor unit 102 to resume a regular heating operation.

[0038]In contrast, the hybrid heat pump system 100 operable as a hybrid top/side discharge heat pump, provides continuous heating during the defrosting mode 400-4. The outdoor fan does not stop during the defrosting mode 400-4 in the hybrid heat pump system 100. This results in a continuous airflow at the hybrid top/side discharge outdoor unit 102 even in the defrosting mode 400-4. The two bi-directional fans of the hybrid top/side discharge outdoor unit 102 force air in opposite direction during the defrosting mode 400-4. The first fan 404-1 draws the outside air into the hybrid top/side discharge outdoor unit 102 and pushes that air downwards to the lower compartment 106. The second fan 404-2 draws and pushes the air upwards to be expelled outside of the upper heat exchanger 414-1 of hybrid top/side discharge outdoor unit 102. In this way, the outdoor airflow does not go through the lower heat exchanger 414-2 of the outdoor coil. The first fan 404-1 and the second fan 404-2 make the airflow bypass the compressor 206 in the defrosting mode 400-4. This results in continuous heating at the lower heat exchanger 414-2 of the hybrid top/side discharge outdoor unit 102 in the defrosting mode 400-4 which melts the frost. The hybrid heat pump system 100 resumes its regular heating operation when the defrosting mode 400-4 ends.

[0039]Referring next to FIG. 5A, a cycle diagram 500-1 of the heat pump of the hybrid heat pump system 100 under a cooling mode 400-1 is shown. The heat pump has a high-pressure switch 502, a low-pressure switch 512, a capillary tube 506, an oil separator 508, and an accumulator 510. The oil separator 508 is the same as the filter-drier 222, used to remove impurities and moisture from the refrigerant to protect the hybrid heat pump system 100. The accumulator 510 collects excess refrigerant to prevent liquid slugging of the compressor 206. The cycle diagram 500-1 has 3 different paths: cooling, heating, and enhanced vapor injection (EVI). The EVI technology is used in heat pumps to improve their efficiency, particularly in low-temperature environments. An EVI system works by injecting a secondary refrigerant into a compression cycle, enhancing heat transfer capabilities of the heat pump. This allows the heat pump to operate effectively even in extreme cold temperatures, which makes the heat pump an energy-efficient and reliable solution for heating.

[0040]A discharge sensor 302-7 on a discharge line carries the high-pressure refrigerant from the compressor 206 to the outdoor heat exchanger 318-1. A cold plate sensor 314 on a liquid line transports a condensed refrigerant to the electronic expansion valve (EEV) 320. A suction sensor 306 returns the low-pressure refrigerant to the compressor 206. Plate heat exchanger 518 transfers heat back to the compressor 206 in low-temperature conditions.

[0041]The outdoor heat exchanger 318-1 transfers heat via the upper heat exchanger 414-1 and the lower heat exchanger 414-2 which are present in the upper and lower compartments 106 of the hybrid top/side discharge outdoor unit 102, respectively. In the cooling mode 400-1, the lower heat exchanger 414-2 takes in air from the outdoor environment. This heat is passed onto the electronic expansion valve (EEV) 320, which reduces the pressure of the liquid refrigerant before the refrigerant turns to the evaporator. The indoor heat exchanger 316 acts as an evaporator and thus absorbs heat from the indoor environment, causing the refrigerant to evaporate. Compressor 206 increases the pressure and temperature of the refrigerant. The outdoor heat exchanger 318-1 acts as a condenser in the cooling mode 400-1. At the upper heat exchanger 414-1, the high-pressure refrigerant releases heat to the outdoor environment and condenses into a liquid.

[0042]Referring next to FIG. 5B, a cycle diagram 500-2 of the heat pump of the hybrid heat pump system 100 under a normal heating mode 400-2 is shown. Every single component of the cycle diagram 500-2 remains the same as in the cooling mode 400-1, but the direction of airflow is now reversed. The outdoor heat exchanger 318-2 acts as an evaporator, and the indoor heat exchanger 316 acts as a condenser in the normal heating mode 400-2.

[0043]The outdoor heat exchanger 318-2 transfers heat via the upper heat exchanger 414-1 and the lower heat exchanger 414-2 present in the upper and lower compartments 106 of the hybrid top/side discharge outdoor unit 102, respectively. In the normal heating mode 400-2, the upper heat exchanger 414-1 draws heat energy from the outdoor environment. Compressor 206 increases the pressure and temperature of the refrigerant. The indoor heat exchanger 316 acts as a condenser in the heating mode. The electronic expansion valve (EEV) 320 reduces the pressure of the refrigerant before the refrigerant enters the evaporator. At the indoor heat exchanger 316, the high-pressure refrigerant releases heat to the indoor environment and condenses into a liquid. The lower heat exchanger 414-2 throws cold air outside the hybrid top/side discharge outdoor unit 102 to continue the heating process.

[0044]Referring next to FIG. 5C, a cycle diagram 500-3 of the heat pump of the hybrid heat pump system 100 under a booster heating mode 400-3 is shown. The airflow during the booster heating mode 400-3 is similar to the normal heating mode 400-2. To extract more heat from the outside air, compressor 206 applies additional pressure, and the temperature of the refrigerant is increased higher as compared to that in the normal heating mode 400-2. The upper heat exchanger 414-1 draws in heat energy, and the outdoor heat exchanger 318-3 acts as an evaporator. The indoor heat exchanger 316 acts as a condenser and heats a closed space. The lower heat exchanger 414-2 expels cold air outside the hybrid top/side discharge outdoor unit 102 to continue the heating process in the booster heating mode 400-3.

[0045]Referring next to FIG. 5D, a cycle diagram 500-4 of the heat pump of the hybrid heat pump system 100 under a defrosting mode 400-4 is shown. In the defrosting mode 400-4, the air flows at the upper compartment 104 of the hybrid top/side discharge outdoor unit 102 alone. The upper heat exchanger 414-1 expels heated air, and the lower heat exchanger 414-2 of the outdoor heat exchanger 318-4 circulates the air. Defrosting happens at the lower compartment 106 of the hybrid top/side discharge outdoor unit 102, while the airflow from the first and second fans 404-1, 404-2 bypasses the compressor 206. During colder outdoor temperatures, usually below 40 to 50° F., and high relative humidities (e.g., above 50%), outdoor coil 204 operates below the frost point of the outdoor air. Frost that builds up on a coil surface is usually removed by reverse-cycle defrost. In the defrosting mode 400-4, the refrigerant flow in the hybrid heat pump system 100 is reversed, and the heated refrigerant from the compressor 206 flows through the outdoor coil 204, melting the frost. A typical defrost takes 4 to 10 min. The outdoor fan 212 is generally off while defrosting. Because defrost is a transient process, capacity, power, and refrigerant pressures and temperatures in different parts of the hybrid heat pump system 100 change throughout a defrost period.

[0046]Referring next to FIG. 6, a hybrid heating method 600 under different modes of the hybrid heat pump system 100, with continuous heating under the defrosting mode 400-4 is shown. At block 602, the hybrid top/side discharge outdoor unit 102 is divided into compartments i.e., the upper compartment 104 and the lower compartment 106. Both these compartments can have heat exchangers with similar or different designs, or the same or different heat exchangers can be used in the upper and the lower compartment 106 i.e., the upper heat exchanger 414-1 and the lower heat exchanger 414-2.

[0047]At block 604, compressor 206 is placed in the lower compartment 106 of the hybrid top/side discharge outdoor unit 102. Compressor 206 is the main component of the hybrid heat pump system 100, and it can compress the refrigerant, increasing its pressure and temperature.

[0048]At block 606, the upper compartment 104 is divided into a left portion 104-1 and a right portion 104-2. This structure makes the heat exchanger of the hybrid heat pump system 100, different from traditional heat pumps. This results in continuous heating at the hybrid top/side discharge outdoor unit 102 in the defrosting mode 400-4.

[0049]At block 608, two bi-directional fans, including the first fan 404-1 and the second fan 404-2, are installed at the left and right portion of the upper compartment 104 respectively. With the ability to reverse a rotational direction of the fan blades, the bi-directional fans help in increasing heating efficiency during colder months by redistributing warm air that rises to the ceiling, and in warmer months, the bi-directional fans can aid in cooling by creating a wind-chill effect.

[0050]At block 610, the hybrid heating method 600 determines the mode of operation of the heat pump. The hybrid top/side discharge outdoor unit 102 operates under four different modes, including the cooling mode 400-1, the normal heating mode 400-2, the booster heating mode 400-3, and the defrosting mode 400-4. At block 612, if the hybrid heat pump system 100 is in the cooling mode 400-1, then both bi-directional fans push air upwards at block 618. After this point, the cooling mode 400-1 comes to an end.

[0051]Otherwise, if the hybrid heat pump system 100 is not in cooling mode 400-1 and is in the normal heating mode 400-2 or the booster heating mode 400-3 at block 614, then both bi-directional fans push air downwards at block 620. In contrast, if the hybrid heat pump system 100 is neither in heating mode nor in cooling mode, that means the hybrid heat pump system 100 is in the defrosting mode 400-4 at block 616.

[0052]At block 622, the bi-directional fans push air in the opposite direction in the defrosting mode 400-4. This means that the first fan 404-1 pushes air downwards and the second fan 404-2 pushes air upwards. In this way, the airflow due to the bi-directional fans bypasses compressor 206, resulting in defrosting at the lower compartment 106 of the hybrid top/side discharge outdoor unit 102.

[0053]Finally, at block 624, the upper heat exchanger 414-1 and lower heat exchanger 414-2 of the upper compartment 104 and the lower compartment 106 provide continuous heating at the hybrid top/side discharge outdoor unit 102 in case of heating and the defrosting mode 400-4. In one example, the hybrid heat pump system 100 has the solar panel 108 at the top which generally converts light energy into electrical energy which is then stored in a power storage device, such as a battery, for smooth functioning of the heat pump in adverse weather conditions.

[0054]Specific details are given in the above description to provide a thorough understanding of the embodiments. However, it is understood that the embodiments may be practiced without these specific details. For example, circuits may be shown in block diagrams in order not to obscure the embodiments in unnecessary detail. In other instances, well-known circuits, processes, algorithms, structures, and techniques may be shown without unnecessary detail in order to avoid obscuring the embodiments.

[0055]Implementation of the techniques, blocks, steps and means described above may be done in various ways. For example, these techniques, blocks, steps and means may be implemented in hardware, software, or a combination thereof. For a hardware implementation, the processing units may be implemented within one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, micro-controllers, microprocessors, other electronic units designed to perform the functions described above, and/or a combination thereof.

[0056]Also, it is noted that the embodiments may be described as a process that is depicted as a flowchart, a flow diagram, a swim diagram, a data flow diagram, a structure diagram, or a block diagram. Although a depiction may describe the operations as a sequential process, many of the operations can be performed in parallel or concurrently. In addition, the order of the operations may be re-arranged. A process is terminated when its operations are completed but could have additional steps not included in the figure. A process may correspond to a method, a function, a procedure, a subroutine, a subprogram, etc. When a process corresponds to a function, its termination corresponds to a return of the function to the calling function or the main function.

[0057]Furthermore, embodiments may be implemented by hardware, software, scripting languages, firmware, middleware, microcode, hardware description languages, and/or any combination thereof. When implemented in software, firmware, middleware, scripting language, and/or microcode, the program code or code segments to perform the necessary tasks may be stored in a machine-readable medium such as a storage medium. A code segment or machine-executable instruction may represent a procedure, a function, a subprogram, a program, a routine, a subroutine, a module, a software package, a script, a class, or any combination of instructions, data structures, and/or program statements. A code segment may be coupled to another code segment or a hardware circuit by passing and/or receiving information, data, arguments, parameters, and/or memory contents. Information, arguments, parameters, data, etc. may be passed, forwarded, or transmitted via any suitable means including memory sharing, message passing, token passing, network transmission, etc.

[0058]For a firmware and/or software implementation, the methodologies may be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. Any machine-readable medium tangibly embodying instructions may be used in implementing the methodologies described herein. For example, software codes may be stored in a memory. Memory may be implemented within the processor or external to the processor. As used herein the term “memory” refers to any type of long term, short term, volatile, nonvolatile, or other storage medium and is not to be limited to any particular type of memory or number of memories, or type of media upon which memory is stored.

[0059]Moreover, as disclosed herein, the term “storage medium” may represent one or more memories for storing data, including read-only memory (ROM), random access memory (RAM), magnetic RAM, core memory, magnetic disk storage mediums, optical storage mediums, flash memory devices and/or other machine-readable mediums for storing information. The term “machine-readable medium” includes but is not limited to portable or fixed storage devices, optical storage devices, and/or various other storage mediums capable of storing that contain or carry instruction(s) and/or data.

[0060]While the principles of the disclosure have been described above in connection with specific apparatuses and methods, it is to be clearly understood that this description is made only by way of example and not as a limitation on the scope of the disclosure.