CN112128972A - Air source heat pump hot water unit - Google Patents

Abstract

The invention discloses an air source heat pump hot water unit, comprising a compressor, a four-way reversing valve, a water-refrigerant heat exchange system, a liquid accumulator, an economizer system, a main expansion valve, a defrosting check valve, an air ‑Refrigerant heat exchange system, gas-liquid separator. The water-refrigerant heat exchange system includes a water-refrigerant heat exchanger which is divided into several groups of independent heat exchange circuits on the refrigerant side, a solenoid valve and a check valve connected to the interface of the water-refrigerant heat exchanger. The on-off of the solenoid valve connected to the interface of the water-refrigerant heat exchanger realizes the change of the heat exchange area of the water-refrigerant heat exchanger, thereby maintaining the condensing pressure within a reasonable range during heating at low water temperature and ensuring the stable operation of the unit , With suitable evaporation pressure and suitable ambient fin temperature difference, the unit can quickly output heating.

Description

Air source heat pump hot water unit

technical field

The invention relates to the technical field of air source heat pumps, and more particularly to an air source heat pump water heater.

Background technique

In recent years, low ambient temperature air source heat pump (chiller) units have been used more and more in the heating field in northern China. This type of heat pump system is mainly composed of compressor, water-refrigerant heat exchanger, main expansion valve, economizer system, fin coil heat exchanger and other main components. If this type of heating unit is to be directly used as a hot water unit for producing domestic hot water, because the hot water unit needs to periodically heat the low-temperature cold water to the required water temperature, the hot water unit needs to work at low water temperature for a long time, but the low temperature Water temperature operation can cause the following problems:

In the first aspect, when the water temperature is low, the pressure on the condensing side is low. Due to the problem of refrigerant supply, the evaporation pressure will move to a lower pressure, which will cause a larger difference between the ambient temperature and the local fin temperature, resulting in the fin coil. The problem that the heat exchanger is more prone to frost; the second aspect, the low pressure on the condensing side will also cause the unstable operation of the scroll compressor scroll that is commonly used; the third aspect, the decline of the evaporation pressure and the scroll The unstable operation of the disk will affect the normal output of the unit.

SUMMARY OF THE INVENTION

One object of the present invention is to provide an air source heat pump hot water unit, wherein the air source heat pump hot water unit can ensure that the condensing pressure is within a reasonable range, ensure that the unit operates stably, has a suitable evaporation pressure and a suitable environment And the fin temperature difference, and then ensure the output of the unit.

Another object of the present invention is to provide an air source heat pump hot water unit, wherein the air source heat pump hot water unit can effectively remove the frost condensed on the heat exchanger during operation, improve the heat exchange efficiency, and reduce the Energy consumption, but also improve the service life of the unit.

Another object of the present invention is to provide a direct expansion air conditioning system, wherein the direct expansion air conditioning system is flexible in installation and operation, and is also very energy-saving in operation and has high usability.

In order to achieve at least one of the above objectives, the present invention provides an air source heat pump hot water unit, including a compressor, a four-way reversing valve, a water-refrigerant heat exchange system, a liquid accumulator, an economizer system, a main expansion valve, Air-refrigerant heat exchange system and gas-liquid separator; the four-way reversing valve has four ports, D port, C port, E port and S port, and the exhaust port of the compressor is connected to the four-way reversing valve D port of the water-refrigerant heat exchange system, the gas phase main line and the liquid phase main line of the water-refrigerant heat exchange system are respectively connected with the C port of the four-way reversing valve and the liquid accumulator, the liquid accumulator, the The economizer system, the main expansion valve and the air-refrigerant heat exchange system are connected in sequence, the air-refrigerant heat exchange system is connected to the E port of the four-way reversing valve, and the gas-liquid separator Both ends are respectively connected with the S port of the four-way reversing valve and the suction port of the compressor.

In one of the embodiments, the water-refrigerant heat exchange system includes a water-refrigerant heat exchanger, and a first solenoid valve and a second solenoid valve connected to the water-refrigerant heat exchanger. The on-off of the first solenoid valve and the second solenoid valve is used to control the heat exchange area of the water-refrigerant heat exchanger.

In one embodiment, the water-refrigerant heat exchanger has two sets of mutually independent heat exchange circuits on the refrigerant side, the interface A1 and the interface A2 are the inlet and outlet interfaces of the first circuit respectively, the interface B1 and the interface B2 are respectively is the inlet and outlet interface of the second circuit; the gas phase main circuit has a first gas phase branch and a second gas phase branch, the first gas phase branch is connected with the interface A1, and the second gas phase branch is connected with the The first solenoid valve is connected to the interface B1; the main liquid-phase pipeline has a first liquid-phase branch and a second liquid-phase branch, the first liquid-phase branch is connected to the interface A2, and the The second gas phase branch is connected to the second solenoid valve and to the interface B2.

In one of the embodiments, the water-refrigerant heat exchange system further includes a first check valve and a second check valve, the first check valve is connected in parallel with the first solenoid valve, and the second check valve is connected in parallel with the first solenoid valve. The one-way valve is connected in parallel with the second solenoid valve; the flow direction of the first one-way valve is directed to the gas phase main line, and the flow direction of the second one-way valve is directed to the liquid phase main line.

In one of the embodiments, the water-refrigerant heat exchanger is a dry shell and tube heat exchanger.

In one embodiment, the economizer system includes an economizer for cooling the primary circuit refrigerant, a secondary circuit solenoid valve, a secondary circuit expansion valve and a secondary circuit check valve, the economizer and the accumulator connected, and the secondary circuit drawn from the primary circuit between the economizer and the accumulator is sequentially connected to the secondary circuit solenoid valve, the secondary circuit expansion valve, the economizer, and the secondary circuit one-way valve and the compressor, the economizer is also connected to the main expansion valve.

In one of the embodiments, the air-refrigerant heat exchange system includes an air-refrigerant heat exchanger and an axial flow fan or an axial flow fan group whose air volume can be adjusted, and the air-refrigerant heat exchanger is respectively connected to the The main expansion valve is connected to the E port of the four-way reversing valve.

In one embodiment, a first filter is arranged between the accumulator and the economizer system, and a second filter is arranged between the main expansion valve and the air-refrigerant heat exchange system .

In one embodiment, the air source heat pump water heater further includes a defrost check valve, one end of the defrost check valve is connected between the main expansion valve and the economizer, and the other end is connected between the accumulator and the first filter, and the flow direction of the defrosting check valve is directed toward the accumulator side of the main expansion valve.

In one embodiment, the reservoir is a bidirectional flow reservoir.

Further objects and advantages of the present invention will be fully realized by an understanding of the ensuing description and drawings.

These and other objects, features and advantages of the present invention are fully embodied by the following detailed description, drawings and claims.

Description of drawings

These and/or other aspects and advantages of the present invention will become clearer and more readily understood from the following detailed description of embodiments of the present invention in conjunction with the accompanying drawings, wherein:

FIG. 1 illustrates a schematic structural diagram of an air source heat pump hot water unit according to an embodiment of the present invention.

FIG. 2 illustrates a schematic diagram of a tube sheet layout of a heat exchanger according to an embodiment of the present invention.

In the picture:

1-air source heat pump hot water unit; 10-compressor; 20-four-way reversing valve; 30-water-refrigerant heat exchange system; 31-water-refrigerant heat exchanger; 32-first solenoid valve; 33 -First check valve; 34 - Second solenoid valve; 35 - Second check valve; 310 - Gas main line; 311 - First gas phase branch; 312 - First gas phase branch; ; 321- the first liquid phase branch; 322- the second liquid phase branch; 40- accumulator; 50- economizer system; 51- auxiliary circuit solenoid valve; 52- auxiliary circuit expansion valve; 53- economizer; 54-Secondary circuit check valve; 60-Main expansion valve; 70-Air-refrigerant heat exchange system; 71-Air-refrigerant heat exchanger; 72-Axial flow fan; 80-Gas-liquid separator 90-Defrosting One-way valve; 100-first filter; 110-second filter.

Detailed ways

The terms and words used in the following specification and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the present invention. Accordingly, it is apparent to those skilled in the art that the following description of various embodiments of the present invention is provided for illustration purposes only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

It should be understood that the term "a" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be one. The number may be plural, and the term "one" should not be understood as a limitation on the number.

Although ordinals such as "first," "second," etc. will be used to describe various components, those components are not limited herein. This term is only used to distinguish one component from another. For example, a first component could be termed a second component, and similarly, a second component could be termed a first component, without departing from the teachings of the inventive concept. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The terminology used herein is for the purpose of describing the various embodiments only and is not intended to be limiting. As used herein, the singular form is intended to include the plural form as well, unless the context clearly dictates an exception. It will also be understood that the terms "comprising" and/or "having" when used in this specification designate the presence of stated features, numbers, steps, operations, components, elements or combinations thereof, without excluding one or more other features , number, step, operation, component, element or the presence or addition of a group thereof.

FIG. 1 is a schematic structural diagram of an air source heat pump hot water unit according to an embodiment of the present invention. As shown in FIG. 1 , the air source heat pump hot water unit 1 includes a compressor 10, a four-way reversing valve 20, a water-refrigerant Heat exchange system 30, liquid accumulator 40, economizer system 50, main expander 60, air-refrigerant heat exchange system 70 and gas-liquid separator 80; wherein the four-way reversing valve 20 has D port and C port , E port, S port four ports, the exhaust port of the compressor 10 is connected to the D port of the four-way reversing valve 20, the gas phase main circuit 310 of the water-refrigerant heat exchange system 30 and the liquid phase The main pipeline 320 is respectively connected to the C port of the four-way reversing valve 20 and the accumulator 40, the accumulator 40 is connected to the economizer system 50, and the economizer system 50 is connected to the main expansion valve valve 60, the main expansion valve 60 is connected to the air-refrigerant heat exchange system 70, the air-refrigerant heat exchange system 70 is connected to the E port of the four-way reversing valve 20, the gas-liquid separator Both ends of 80 are respectively connected with the S port of the four-way reversing valve 20 and the suction port of the compressor 20, and are connected in this way to form a complete system circuit.

Further, the compressor 20 is a jet enthalpy increasing scroll compressor or a jet enthalpy increasing rotary compressor.

Specifically, the water-refrigerant heat exchange system 30 includes a water-refrigerant heat exchanger 31 and a first solenoid valve 32 and a second solenoid valve 34 connected to the water-refrigerant heat exchanger 31, as shown in FIG. As shown in 2, the refrigerant side of the water-refrigerant heat exchanger 31 is divided into two independent circuits, wherein the interface A1 and the interface A2 are the inlet and outlet interfaces of the first circuit respectively, and the interface B1 and the interface B2 are the first circuit respectively. The inlet and outlet ports of the secondary circuit; the gas-phase main circuit 310 of the water-refrigerant heat exchange system 30 is divided into a first gas-phase branch 311 and a second gas-phase branch 312, and the first gas-phase branch 311 is connected to the water-refrigeration system the interface A1 of the refrigerant heat exchanger 31, the second gas phase branch 312 is connected to the first solenoid valve 32; the liquid main circuit 320 of the water-refrigerant heat exchange system 30 is divided into the first liquid branch 321 and the The second liquid-phase branch 322, the first liquid-phase branch 321 is connected to the A2 interface of the water-refrigerant heat exchanger 31, the second liquid-phase branch 322 is connected to the second solenoid valve 34, and is controlled by The on-off of the first solenoid valve 32 and the second solenoid valve 34 is used to control the change of the actual input heat exchange area of the water-refrigerant heat exchanger 30 .

More specifically, the water-refrigerant heat exchange system 30 further includes a first one-way valve 33 and a second one-way valve 35, the first one-way valve 33 is connected in parallel with the first solenoid valve 32, and is connected to the The interface B1 of the water-refrigerant heat exchanger 30, the second one-way valve 35 is connected in parallel with the second solenoid valve 34, and connected to the interface B2 of the water-refrigerant heat exchanger 30 after confluence; wherein , the flow direction of the first one-way valve 33 is directed to the gas phase main line 310 , and the flow direction of the second one-way valve 35 is directed to the liquid phase main line 320 .

Preferably, the water-refrigerant heat exchanger 30 is a dry shell and tube heat exchanger. As shown in FIG. 2 , the pipe layout areas A1, A2, B1, and B2 in the figure correspond to the interface A1, the interface A2, and the interface respectively. B1, interface B2, the heat exchange tubes in the A1 and A2 areas are an independent heat exchange circuit, the heat exchange tubes in the B1 and B2 areas are an independent heat exchange circuit, and the refrigerant cover matched with the tube sheet separates each area Come on, don't interfere with each other. It should be understood that the water-refrigerant heat exchanger may also be a pan-tank heat exchanger or a multi-core casing heat exchanger, which is not specifically limited in the present invention.

More preferably, a first filter 100 is arranged between the accumulator 40 and the economizer system 60 , and a second filter 100 is arranged between the main expansion valve 60 and the air-refrigerant heat exchange system 70 . The filter 110, wherein, in the embodiment of the present invention, the first filter 100 and the second filter 110 are bidirectional flow filters or bidirectional flow drying filters.

Further, the economizer system 50 includes an economizer 53 connected to the first filter 110, and a secondary circuit is branched from the main circuit between the economizer 53 and the first filter 100, The secondary circuit is sequentially connected to the secondary circuit solenoid valve 51, the secondary circuit expansion valve 52, the economizer 53, the secondary circuit check valve 54 and the compressor 10; the economizer 53 is also connected to the The main expansion valve 60 is connected to each other. Preferably, the auxiliary circuit expansion valve 52 is an electronic expansion valve, the economizer 53 is a plate heat exchanger or a shell and tube heat exchanger, and the main expansion valve 60 is a two-way flow. A thermal expansion valve or a bidirectional flow electronic expansion valve is not specifically limited in the present invention.

Further, the air-refrigerant heat exchange system 70 includes an air-refrigerant heat exchanger 71 and an axial flow fan 72. The axial flow fan 72 is used to adjust the air volume to ensure that the evaporation pressure is within a reasonable range. The air-refrigerant heat exchanger 71 is connected to the main expansion valve 60 and the E port of the four-way reversing valve 20 respectively; preferably, the axial flow fan 72 adopts a variable frequency axial flow fan or a variable frequency axial flow fan , the air-refrigerant heat exchanger 71 adopts a fin coil type heat exchanger. It should be understood that the axial flow fan 72 can also be replaced with an axial flow fan unit in the form of a combination of fixed frequency axial flow fans. It is not specifically limited in the present invention.

Specifically, the air source heat pump hot water unit 1 further includes a defrost check valve 90, one end of the defrost check valve 90 is connected between the main expansion valve 60 and the economizer system 50, and the other end is connected to the liquid storage between the filter 40 and the first filter 100, and the flow direction of the defrost check valve 90 is directed to the side of the main expansion valve 60 toward the side of the accumulator 40.

When the air source heat pump hot water unit 1 is heating, the flow direction of the refrigerant is the exhaust port of the compressor 10, the four-way reversing valve 20, the water-refrigerant heat exchange system 30, the accumulator 40, the first filter 100, the economizer system 50, the main expansion valve 60, the second filter 110, the air-refrigerant heat exchange system 70, the four-way reversing valve 20, the gas-liquid separator 80, the suction port of the compressor 10, the said The water-refrigerant heat exchange system 30 determines the on-off of the first solenoid valve 32 and the second solenoid valve 34 in the water-refrigerant heat exchange system 30 according to the water temperature or the high pressure of the refrigeration system, so as to put in a suitable The heat exchange area of the water-refrigerant heat exchanger 31 ensures that the condensation pressure is within a reasonable range.

When the air source heat pump hot water unit 1 adopts the four-way reversing valve 20 to switch reverse defrosting, the flow direction of the refrigerant is the exhaust port of the compressor 10, the four-way reversing valve 20, the The air-refrigerant heat exchange system 70, the second filter 110, the main expansion valve 60, the defrost check valve 90, the accumulator 40, the water-refrigerant heat exchange system 30. The four-way reversing valve 20 and the gas-liquid separator 80 finally flow into the suction port of the compressor 10.

When the air source heat pump hot water unit 1 provided by the present invention is started and operated at a low water temperature, by controlling the on-off of the solenoid valve in the water-refrigerant heat exchange system 30, a suitable water-refrigerant heat exchange area is put in, This ensures that the condensing pressure is within a reasonable range, ensures the stable operation of the unit, has a suitable evaporation pressure, and has a suitable environment and fin temperature difference, thereby ensuring the output of the unit; at the same time, the air source heat pump hot water unit 1 passes through the four-way The reversing valve 20 switches to reverse defrosting, which improves the heat exchange efficiency, reduces the energy consumption, and also increases the service life of the unit.

The basic principles of the present invention have been described above in conjunction with specific embodiments. However, it should be pointed out that the advantages, advantages, effects, etc. mentioned in the present invention are only examples rather than limitations, and these advantages, advantages, effects, etc. are not considered to be A must-have for each embodiment of the present invention. In addition, the specific details disclosed above are only for the purpose of example and easy understanding, rather than limiting, and the above-mentioned details do not limit the present invention to be implemented by the above-mentioned specific details.

The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the scope of the invention. Thus, the present invention is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

The foregoing description has been presented for the purposes of illustration and description. Furthermore, this description is not intended to limit embodiments of the invention to the forms disclosed herein. Although a number of example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims (10)

1. An air source heat pump hot water unit, characterized in that, comprising a compressor, a four-way reversing valve, a water-refrigerant heat exchange system, a liquid accumulator, an economizer system, a main expansion valve, an air-refrigerant exchange Thermal systems and gas-liquid separators; The four-way reversing valve has four ports: D port, C port, E port, and S port. The exhaust port of the compressor is connected to the D port of the four-way reversing valve. The water-refrigerant heat exchange system The main gas phase pipeline and the liquid phase main pipeline are respectively connected with the C port of the four-way reversing valve and the liquid accumulator, the liquid accumulator, the economizer system, the main expansion valve and the air - The refrigerant heat exchange system is connected in sequence, the air-refrigerant heat exchange system is connected to the E port of the four-way reversing valve, and the two ends of the gas-liquid separator are respectively connected to the S port of the four-way reversing valve. The port is connected to the suction port of the compressor. 2. The air source heat pump hot water unit according to claim 1, wherein the water-refrigerant heat exchange system comprises a water-refrigerant heat exchanger, and is connected to the water-refrigerant heat exchanger The first solenoid valve and the second solenoid valve are controlled to control the heat exchange area of the water-refrigerant heat exchanger by controlling the on-off of the first solenoid valve and the second solenoid valve. 3. The air source heat pump hot water unit according to claim 2, wherein the water-refrigerant heat exchanger has two sets of mutually independent heat exchange circuits on the refrigerant side, and the interface A1 and the interface A2 are respectively The inlet and outlet interfaces of the first circuit, the interface B1 and the interface B2 are respectively the inlet and outlet interfaces of the second circuit; the main gas phase pipeline has a first gas phase branch and a second gas phase branch, and the first gas phase branch is connected to the interface. A1 is connected, the second gas phase branch is connected to the first solenoid valve and is connected to the interface B1; the liquid main circuit has a first liquid phase branch and a second liquid phase branch, the first liquid phase branch The liquid phase branch is connected to the interface A2, and the second gas phase branch is connected to the second solenoid valve and connected to the interface B2. 4. The air source heat pump hot water unit according to claim 3, wherein the water-refrigerant heat exchange system further comprises a first check valve and a second check valve, the first check valve It is connected in parallel with the first solenoid valve, and the second one-way valve is connected in parallel with the second solenoid valve; the flow direction of the first one-way valve points to the main gas phase pipeline, and the The flow direction points to the main liquid phase circuit. 5. The air source heat pump hot water unit according to claim 2, wherein the water-refrigerant heat exchanger is a dry shell and tube heat exchanger. 6. The air source heat pump hot water unit according to claim 1, wherein the economizer system comprises an economizer for cooling the refrigerant in the primary circuit, a solenoid valve in the secondary circuit, an expansion valve in the secondary circuit, and a single circuit in the secondary circuit. The economizer is connected to the accumulator, and the auxiliary circuit drawn from the main circuit between the economizer and the accumulator is connected to the auxiliary circuit solenoid valve and the auxiliary circuit expansion valve in turn. valve, the economizer, the secondary circuit check valve and the compressor, the economizer is also connected to the main expansion valve. 7. The air source heat pump hot water unit according to claim 1, wherein the air-refrigerant heat exchange system comprises an air-refrigerant heat exchanger and an axial flow fan or an axial flow fan group that can adjust the air volume , the air-refrigerant heat exchanger is respectively connected with the main expansion valve and the E port of the four-way reversing valve. 8 . The air source heat pump water heater according to claim 1 , wherein a first filter is provided between the accumulator and the economizer system, and the main expansion valve and the air- A second filter is provided between the refrigerant heat exchange systems. 9 . The air source heat pump hot water unit according to claim 8 , further comprising a defrosting check valve, one end of the defrosting check valve is connected between the main expansion valve and the economizer. 10 . The other end is connected between the accumulator and the first filter, and the flow direction of the defrosting check valve is directed to the accumulator side by the main expansion valve. 10 . The air source heat pump hot water unit according to claim 1 , wherein the accumulator is a bidirectional flow accumulator. 11 .

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