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CN110494699B - Outdoor unit of heat pump type water heater - Google Patents

Outdoor unit of heat pump type water heater Download PDF

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Publication number
CN110494699B
CN110494699B CN201780089153.XA CN201780089153A CN110494699B CN 110494699 B CN110494699 B CN 110494699B CN 201780089153 A CN201780089153 A CN 201780089153A CN 110494699 B CN110494699 B CN 110494699B
Authority
CN
China
Prior art keywords
heat exchanger
outdoor unit
air
fan
compressor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CN201780089153.XA
Other languages
Chinese (zh)
Other versions
CN110494699A (en
Inventor
菊川觉
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Electric Corp
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Mitsubishi Electric Corp
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Filing date
Publication date
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Publication of CN110494699A publication Critical patent/CN110494699A/en
Application granted granted Critical
Publication of CN110494699B publication Critical patent/CN110494699B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H4/00Fluid heaters characterised by the use of heat pumps
    • F24H4/02Water heaters
    • F24H4/04Storage heaters
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24DDOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
    • F24D19/00Details
    • F24D19/10Arrangement or mounting of control or safety devices
    • F24D19/1006Arrangement or mounting of control or safety devices for water heating systems
    • F24D19/1051Arrangement or mounting of control or safety devices for water heating systems for domestic hot water
    • F24D19/1054Arrangement or mounting of control or safety devices for water heating systems for domestic hot water the system uses a heat pump
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F1/00Room units for air-conditioning, e.g. separate or self-contained units or units receiving primary air from a central station
    • F24F1/06Separate outdoor units, e.g. outdoor unit to be linked to a separate room comprising a compressor and a heat exchanger
    • F24F1/20Electric components for separate outdoor units
    • F24F1/24Cooling of electric components
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00Control of fluid heaters
    • F24H15/20Control of fluid heaters characterised by control inputs
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00Control of fluid heaters
    • F24H15/20Control of fluid heaters characterised by control inputs
    • F24H15/258Outdoor temperature
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00Control of fluid heaters
    • F24H15/30Control of fluid heaters characterised by control outputs; characterised by the components to be controlled
    • F24H15/375Control of heat pumps
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00Control of fluid heaters
    • F24H15/30Control of fluid heaters characterised by control outputs; characterised by the components to be controlled
    • F24H15/375Control of heat pumps
    • F24H15/38Control of compressors of heat pumps
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00Control of fluid heaters
    • F24H15/30Control of fluid heaters characterised by control outputs; characterised by the components to be controlled
    • F24H15/375Control of heat pumps
    • F24H15/385Control of expansion valves of heat pumps
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00Control of fluid heaters
    • F24H15/40Control of fluid heaters characterised by the type of controllers
    • F24H15/414Control of fluid heaters characterised by the type of controllers using electronic processing, e.g. computer-based
    • F24H15/421Control of fluid heaters characterised by the type of controllers using electronic processing, e.g. computer-based using pre-stored data
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00Control of fluid heaters
    • F24H15/40Control of fluid heaters characterised by the type of controllers
    • F24H15/486Control of fluid heaters characterised by the type of controllers using timers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H9/00Details
    • F24H9/20Arrangement or mounting of control or safety devices
    • F24H9/2007Arrangement or mounting of control or safety devices for water heaters
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24DDOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
    • F24D17/00Domestic hot-water supply systems
    • F24D17/02Domestic hot-water supply systems using heat pumps
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24DDOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
    • F24D2200/00Heat sources or energy sources
    • F24D2200/12Heat pump
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F1/00Room units for air-conditioning, e.g. separate or self-contained units or units receiving primary air from a central station
    • F24F1/06Separate outdoor units, e.g. outdoor unit to be linked to a separate room comprising a compressor and a heat exchanger
    • F24F1/38Fan details of outdoor units, e.g. bell-mouth shaped inlets or fan mountings

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Computer Hardware Design (AREA)
  • Heat-Pump Type And Storage Water Heaters (AREA)

Abstract

An outdoor unit (2) of a heat pump water heater according to the present invention comprises: an air heat exchanger (7); a compressor (10); a water heat exchanger (4); an expansion valve; a fan (8) that moves air outside the outdoor unit (2) toward the air heat exchanger (7); a motor that rotates the fan (8); a power element (16) for driving the compressor (10); a heat sink (15) which is located in a space (42) in which a passage (41) for air that moves from the outside of the outdoor unit (2) to the air heat exchanger (7) as the fan (8) rotates when heating water extends beyond the air heat exchanger (7), and which dissipates heat generated by the power element (16) when the compressor (10) is driven; and a control unit that drives the compressor (10) to open the expansion valve and rotates the fan (8) in the same direction as the rotation direction of the fan (8) when the water heating process is completed.

Description

Outdoor unit of heat pump type water heater
Technical Field
The present invention relates to an outdoor unit of a heat pump water heater for heating water.
Background
Conventionally, a heat pump water heater for heating water has been used. For example, heat pump water heaters are used for boiling. The heat pump water heater includes an outdoor unit that heats water and a water heater tank unit that stores water. The outdoor unit includes an air heat exchanger, a fan for moving air outside the outdoor unit to the air heat exchanger, a motor for rotating the fan, a compressor for compressing a refrigerant, a water heat exchanger, a power element for controlling the compressor and the motor, and a heat sink for diffusing heat generated by the power element when the compressor is driven.
Conventionally, when the boiling operation is completed, the air heat exchanger is cooled, and the heat sink is also cooled by the influence of the cooled air heat exchanger. When the heat sink is cooled, condensation may occur on the surface of the power element. If dew condensation occurs on the surface, current leakage may occur in the power element, and the power element may not operate normally. The following techniques are proposed: when condensation is likely to occur, the temperature of the power element is prevented from rising and condensation is prevented from occurring on the surface of the power element by increasing the rotation speed of the compressor per unit time or by increasing the switching loss of the switching element constituting the power element (see, for example, patent document 1).
Patent document 1: japanese patent application laid-open No. 2010-25373
However, in the above-described conventional technique, the heat sink is cooled down after the water heating process is completed and the operation of the power element is stopped, and therefore dew condensation may occur on the surface of the power element.
Disclosure of Invention
The present invention has been made in view of the above problems, and an object of the present invention is to provide an outdoor unit of a heat pump water heater in which condensation is less likely to occur in a power element after a water heating process is completed.
In order to solve the above problems and achieve the object, an outdoor unit of a heat pump water heater according to the present invention includes: an air heat exchanger for performing heat exchange between air outside the outdoor unit and the refrigerant; a compressor capable of compressing the refrigerant flowing out of the air heat exchanger; a water heat exchanger for exchanging heat between the refrigerant flowing out of the compressor and water; an expansion valve capable of reducing the pressure of the refrigerant flowing out of the water heat exchanger; a fan for moving air outside the outdoor unit to the air heat exchanger; a motor for rotating the fan; a power element for driving the compressor, the expansion valve, and the motor; a heat sink located in a space in which a passage of air moving from outside the outdoor unit to the air heat exchanger by the rotation of the fan extends beyond the air heat exchanger when the water is heated, and dissipating heat generated by the power element when the compressor is driven; and a control unit that rotates the fan in a direction opposite to a rotation direction of the fan when the water is heated, when the water heating process is completed.
The outdoor unit of the heat pump water heater according to the present invention has an effect that condensation is less likely to occur in the power element after the water heating process is completed.
Drawings
Fig. 1 is a diagram 1 showing a configuration of a heat pump water heater according to embodiment 1.
Fig. 2 is a cross-sectional view of the outdoor unit of the heat pump water heater according to embodiment 1, when the outdoor unit is viewed from one side surface side of the outdoor unit of the heat pump water heater according to embodiment 1.
Fig. 3 is a cross-sectional view of the outdoor unit of the heat pump water heater according to embodiment 1, when the outdoor unit is viewed from the front side of the outdoor unit of the heat pump water heater according to embodiment 1.
Fig. 4 is a perspective view schematically showing the inside of an outdoor unit of a heat pump water heater according to embodiment 1.
Fig. 5 is a perspective view illustrating an assembly method of a heat sink to a power element assembled on a control board mounted inside an outdoor unit of the heat pump water heater according to embodiment 1.
Fig. 6 is a diagram 2 showing a configuration of a heat pump water heater according to embodiment 1.
Fig. 7 is a flowchart showing a procedure of the operation of the outdoor unit of the heat pump water heater according to embodiment 1.
Fig. 8 is a flowchart showing a procedure of the operation of the outdoor unit of the heat pump water heater according to embodiment 2.
Fig. 9 is a cross-sectional view illustrating the outdoor unit of the heat pump water heater according to embodiment 2 when the outdoor unit is viewed from one side surface side of the outdoor unit of the heat pump water heater according to embodiment 2.
Fig. 10 is a diagram showing a processing circuit in a case where at least some of the components constituting the outdoor unit of the heat pump water heater according to embodiment 1 and embodiment 2 are realized by the processing circuit, the components constituting the communication unit, the control unit, the temperature acquisition unit, the motor drive circuit, the compressor drive circuit, the expansion valve drive circuit, and the timer.
Fig. 11 is a diagram showing a processor in a case where at least a part of functions of a communication unit, a control unit, a temperature acquisition unit, a motor drive circuit, a compressor drive circuit, an expansion valve drive circuit, and a timer included in the outdoor unit of the heat pump water heater according to embodiment 1 and embodiment 2 are realized by the processor.
Detailed Description
Hereinafter, an outdoor unit of a heat pump water heater according to an embodiment of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiment.
Embodiment mode 1
First, the configuration of the heat pump water heater 1 according to embodiment 1 will be described. Fig. 1 is a diagram 1 showing a configuration of a heat pump water heater 1 according to embodiment 1. The heat pump water heater 1 includes an outdoor unit 2 for heating water and a water heater tank unit 3 for storing water. Hereinafter, the "outdoor unit 2 of the heat pump water heater" may be simply referred to as "outdoor unit 2".
The outdoor unit 2 includes a water heat exchanger 4 for exchanging heat between the refrigerant and water. An inflow pipe 5 is connected to the water heat exchanger 4. The inflow pipe 5 is also connected to the water heater tank unit 3. The water stored in the water heater tank unit 3 flows into the water heat exchanger 4 through the inflow pipe 5. The water heat exchanger 4 heats water flowing from the hot water tank unit 3 into the water heat exchanger 4 through the inflow pipe 5 by the heated refrigerant to generate hot water. An outflow pipe 6 is also connected to the water heat exchanger 4. The outlet pipe 6 is also connected to the water heater tank unit 3. The hot water generated in the water heat exchanger 4 moves to the water heater tank unit 3 through the outflow pipe 6 and is accumulated in the water heater tank unit 3.
The outdoor unit 2 further includes an air heat exchanger 7 for exchanging heat between the air outside the outdoor unit 2 and the refrigerant, a fan 8 for moving the air outside the outdoor unit 2 to the air heat exchanger 7, and a motor 9 for rotating the fan 8. An example of the fan 8 is a propeller fan. The outdoor unit 2 further includes a compressor 10 capable of compressing the refrigerant flowing out of the air heat exchanger 7, an expansion valve 11 capable of expanding the compressed refrigerant, and a refrigerant circuit 12 serving as a passage for the refrigerant. The water heat exchanger 4 exchanges heat between the refrigerant flowing out of the compressor 10 and water. The expansion valve 11 can reduce the pressure of the refrigerant flowing out of the water heat exchanger 4. An example of the expansion valve 11 is an electronically controlled expansion valve.
The outdoor unit 2 further includes an exchanger temperature detection sensor 13 for detecting the temperature of the air heat exchanger 7. The exchanger temperature detection sensor 13 is incorporated in a pipe at the outlet of the refrigerant flowing out of the air heat exchanger 7. The pipe is a part of the refrigerant circuit 12. The exchanger temperature detection sensor 13 has, for example, a thermistor, and detects the temperature of the air heat exchanger 7 based on the resistance value of the thermistor.
The air heat exchanger 7 exchanges heat between the refrigerant and the air outside the outdoor unit 2. The refrigerant flowing out of the air heat exchanger 7 is compressed by the compressor 10, and the temperature of the refrigerant rises in the compressor 10. The refrigerant compressed and heated by the compressor 10 flows into the water heat exchanger 4. In the water heat exchanger 4, heat exchange is performed between the refrigerant compressed by the compressor 10 and the water flowing into the water heat exchanger 4 from the hot water tank unit 3, and the water is heated to generate hot water. The refrigerant flows from the water heat exchanger 4 to the expansion valve 11, expands in the expansion valve 11, and then flows into the air heat exchanger 7.
In the outdoor unit 2, a cycle is repeated in which the refrigerant passes through the compressor 10, the water heat exchanger 4, and the expansion valve 11 in this order from the air heat exchanger 7 and returns to the air heat exchanger 7. The outdoor unit 2 further includes an outdoor air temperature detection sensor 14 for detecting an outdoor air temperature of the outdoor unit 2. For example, the outside air temperature detection sensor 14 has a thermistor, and detects the outside air temperature of the outdoor unit 2 based on the resistance value of the thermistor.
Fig. 2 is a cross-sectional view of the outdoor unit 2 of the heat pump water heater according to embodiment 1, when the outdoor unit 2 is viewed from one side surface side of the outdoor unit 2 of the heat pump water heater according to embodiment 1. As shown in fig. 2, the outdoor unit 2 further includes a heat sink 15 that cools power components for driving the motor 9, the compressor 10, and the expansion valve 11. The power element is a semiconductor element. The power elements are not shown in fig. 2.
The heat sink 15 is assembled to, for example, a power element, and is located in a space in which a passage of air that moves from the outside of the outdoor unit 2 to the air heat exchanger 7 by the rotation of the fan 8 when heating water extends beyond the air heat exchanger 7. That is, the heat sink 15 is provided at a position where it collides with the wind generated by the rotation of the fan 8 and passing through the air heat exchanger 7. The heat sink 15 diffuses heat generated from the power element at the time of driving of the compressor 10. The arrows in fig. 2 indicate a case where the wind generated by the rotation of the fan 8 moves from the fan 8 toward the air heat exchanger 7.
Fig. 3 is a cross-sectional view of the outdoor unit 2 of the heat pump water heater according to embodiment 1, when the outdoor unit 2 is viewed from the front side of the outdoor unit 2 of the heat pump water heater according to embodiment 1. As shown in fig. 3, the outdoor unit 2 further includes: a power element 16 for driving the motor 9, the compressor 10, and the expansion valve 11; and a control board 17 for controlling the power element 16 so as to prevent condensation from occurring after the water heating process is completed. The control board 17 is mounted inside the outdoor unit 2, and the power element 16 is mounted on the control board 17.
Fig. 4 is a perspective view schematically showing the inside of the outdoor unit 2 of the heat pump water heater according to embodiment 1. As shown in fig. 4, the heat sink 15 is assembled to the power element 16, for example, and is located in a space 42 in which a passage 41 of air that moves from the outside of the outdoor unit 2 to the air heat exchanger 7 by the rotation of the fan 8 when heating water extends beyond the air heat exchanger 7. The arrows in fig. 4 indicate a case where the wind generated by the rotation of the fan 8 moves from the fan 8 toward the air heat exchanger 7.
Fig. 5 is a perspective view illustrating an assembly method of the heat sink 15 to the power element 16 mounted on the control board 17 in the outdoor unit 2 of the heat pump water heater according to embodiment 1. In embodiment 1, as shown in fig. 5, the power element 16 includes a 1 st power element portion 16a and a 2 nd power element portion 16 b. A 1 st notch 16x is formed in one of a pair of opposing side surfaces of the 1 st power element portion 16a, and a 2 nd notch 16y is formed in the other of the pair of opposing side surfaces.
The 2 nd power element portion 16b is formed with a hole 16z penetrating in the thickness direction. Three through holes are formed in the control board 17. One of the three through holes is a hole 17 a. The 1 st power element portion 16a is assembled to the control substrate 17 such that the 1 st notch 16x of the 1 st power element portion 16a overlaps the hole 17a, and the 2 nd notch 16y of the 1 st power element portion 16a overlaps one through-hole formed in the control substrate 17 other than the hole 17 a. The 2 nd power element portion 16b is assembled to the control substrate 17 such that the hole 16z of the 2 nd power element portion 16b overlaps another through-hole different from the hole 17a formed in the control substrate 17.
The 1 st bolt 18a is inserted into the 1 st hole of the heat sink 15 through the hole 17a and the 1 st cutout 16x, the 2 nd bolt 18b is inserted into the 2 nd hole of the heat sink 15 through the 2 nd cutout 16y, and the 3 rd bolt 18c is inserted into the 3 rd hole of the heat sink 15 through the hole 16 z. The 1 st, 2 nd and 3 rd wells are not shown. Nuts not shown are fitted to the 1 st bolt 18a, the 2 nd bolt 18b, and the 3 rd bolt 18c inserted into corresponding holes of the heat sink 15, and the heat sink 15 is assembled to the power element 16 by the 1 st bolt 18a, the 2 nd bolt 18b, the 3 rd bolt 18c, and the three nuts.
Fig. 6 is a diagram 2 showing a configuration of the heat pump water heater 1 according to embodiment 1. As shown in fig. 6, the water heater tank unit 3 has a communication unit 31 that communicates with the outdoor unit 2. The control board 17 included in the outdoor unit 2 has a communication unit 21 that communicates with the communication unit 31 of the hot water tank unit 3. When the water heating process is completed, the communication unit 21 receives an operation completion signal indicating that the water heating process has been completed from the communication unit 31 of the hot water tank unit 3.
The control board 17 further includes a memory 22, and the memory 22 stores 1 st information indicating a 1 st reference temperature as a lower limit temperature for determining whether or not the dew condensation preventing operation is performed. The dew condensation preventing operation is an operation in which dew condensation is less likely to occur in the power element 16 after the water heating process is completed. The control board 17 further includes: a control unit 23 for controlling the dew condensation preventing operation; and a temperature acquisition unit 24 that acquires information indicating the outside air temperature of the outdoor unit 2 from the outside air temperature detection sensor 14 and acquires information indicating the temperature of the air heat exchanger 7 from the exchanger temperature detection sensor 13.
When the communication unit 21 receives an operation end signal as a signal indicating that the process of heating water has been completed from the communication unit 31 of the hot water tank unit 3, the control unit 23 controls the dew condensation preventing operation when the outdoor unit 2 has an outdoor temperature higher than the 1 st reference temperature indicated by the 1 st information stored in the memory 22, the outdoor temperature being indicated by the information acquired by the temperature acquiring unit 24. Specifically, when the water heating process is completed and the outdoor temperature of the outdoor unit 2 is higher than the 1 st reference temperature, the controller 23 drives the compressor 10, opens the expansion valve 11, and rotates the fan 8 in the same direction as the rotation direction of the fan 8 when heating the water. For example, the controller 23 opens the expansion valve 11 to the full state when the expansion valve 11 is opened. For example, the control unit 23 rotates the fan 8 at a rotation speed slower than that in the case where the treatment of heating the water is performed during the dew condensation preventing operation.
The control board 17 further includes a motor drive circuit 25 for driving the motor 9, a compressor drive circuit 26 for driving the compressor 10, and an expansion valve drive circuit 27 for driving the expansion valve 11. The motor drive circuit 25, the compressor drive circuit 26, and the expansion valve drive circuit 27 are controlled by the control unit 23 to operate.
In the dew condensation prevention operation, the compressor 10 is operated to warm the refrigerant by the compressor 10, and the expansion valve 11 is opened without performing heat exchange in the water heat exchanger 4, so that the refrigerant flowing out of the compressor 10 reaches the air heat exchanger 7 in a warmed state. That is, the temperature of the air heat exchanger 7 is higher than the temperature when the compressor 10 is not operating. Since the fan 8 rotates, the air as the air flowing from the outside of the outdoor unit 2 into the inside of the outdoor unit 2 is heated by the air heat exchanger 7 when passing through the air heat exchanger 7, and the air heated by the air heat exchanger 7 reaches the heat sink 15 to heat the heat sink 15. Thus, even when the water heating process is completed, the heat sink 15 does not decrease in temperature, and dew condensation is less likely to occur on the power element 16.
The control board 17 also has a timer 28 for measuring time. The memory 22 also stores the 2 nd information indicating the 2 nd reference temperature as the lower limit temperature for determining whether or not to end the dew condensation preventing operation after the dew condensation preventing operation is performed. After starting the control of the dew condensation preventing operation, the control unit 23 determines whether or not the temperature of the air heat exchanger 7 indicated by the information acquired by the temperature acquisition unit 24 is equal to or higher than the 2 nd reference temperature indicated by the 2 nd information stored in the memory 22. When determining that the temperature of the air heat exchanger 7 is equal to or higher than the 2 nd reference temperature, the control unit 23 starts the measurement by the timer 28. When the time measured by the timer 28 reaches a time predetermined to end the dew condensation preventing operation, the control unit 23 performs control to stop the operations of the motor 9 and the compressor 10. The predetermined time information is stored in the memory 22.
Next, the operation of the outdoor unit 2 of the heat pump water heater according to embodiment 1 will be described. Fig. 7 is a flowchart showing a procedure of the operation of the outdoor unit 2 of the heat pump water heater according to embodiment 1. The operation of the dew condensation preventing operation will be described below.
The outside air temperature detection sensor 14 detects the outside air temperature (S1). When the communication unit 21 receives an operation end signal as a signal indicating that the process of heating water has been completed from the communication unit 31 of the hot water tank unit 3, the control unit 23 determines whether or not the outdoor unit 2 has an outdoor temperature higher than the 1 st reference temperature that is a reference for starting the dew condensation prevention operation (S2). When it is determined that the outdoor air temperature of the outdoor unit 2 is equal to or lower than the 1 st reference temperature that is a reference for starting the dew condensation prevention operation (no in S2), the control unit 23 does not perform the dew condensation prevention operation.
When determining that the outdoor air temperature of the outdoor unit 2 is higher than the 1 st reference temperature that is a reference for starting the dew condensation prevention operation (yes at S2), the controller 23 operates the compressor 10 and opens the expansion valve 11 (S3). By the operation of step S3, the temperature of the air heat exchanger 7 becomes higher than the temperature of the air heat exchanger 7 when the compressor 10 is not operating. The control unit 23 drives the motor 9 and rotates the fan 8 (S4).
The exchanger temperature detection sensor 13 detects the temperature of the air heat exchanger 7 (S5). The control unit 23 determines whether or not the temperature of the air heat exchanger 7 is equal to or higher than the 2 nd reference temperature indicated by the 2 nd information stored in the memory 22 (S6). If the controller 23 determines that the temperature of the air heat exchanger 7 is lower than the 2 nd reference temperature (no in S6), the operation of the outdoor unit 2 proceeds to step S5. When it is determined that the temperature of the air heat exchanger 7 is equal to or higher than the 2 nd reference temperature (yes in S6), the controller 23 stops the operation of the fan 8 and the compressor 10 after a predetermined time has elapsed from when it is determined that the temperature of the air heat exchanger 7 is equal to or higher than the 2 nd reference temperature (S7). That is, in step S7, the control unit 23 stops the operation of the fan 8 and the compressor 10 after a predetermined time has elapsed since the determination that the temperature of the air heat exchanger 7 is equal to or higher than the 2 nd reference temperature.
As described above, when the water heating process is completed, the controller 23 of the outdoor unit 2 drives the compressor 10 to open the expansion valve 11 and rotate the fan 8 in the same direction as the rotation direction of the fan 8 when heating the water. The refrigerant is warmed by the compressor 10 under the control of the control unit 23, and the heat exchange is not performed in the water heat exchanger 4, and the expansion valve 11 is opened, so that the refrigerant flowing out of the compressor 10 reaches the air heat exchanger 7 in a warmed state. That is, the temperature of the air heat exchanger 7 is higher than the temperature when the compressor 10 is not operating. Further, the temperature of the air heat exchanger 7 becomes higher than the temperature around the air heat exchanger 7.
Since the fan 8 rotates, the air as the air flowing into the outdoor unit 2 from the outside of the outdoor unit 2 is heated in the air heat exchanger 7 when passing through the air heat exchanger 7. The air warmed in the air heat exchanger 7 reaches the radiator 15. The heated air reaches the heat sink 15, so the heat sink 15 does not cool. Since the heat sink 15 does not cool down, dew condensation is less likely to occur in the power element 16 even after the water heating process is completed. That is, the outdoor unit 2 of the heat pump water heater can prevent condensation from occurring in the power element 16 after the water heating process is completed.
As described above, when the temperature of the air heat exchanger 7 is equal to or higher than the 2 nd reference temperature after the dew condensation preventing operation is started, the controller 23 stops the dew condensation preventing operation when a certain time period has elapsed during which it can be determined that the heat sink 15 has been sufficiently warmed. That is, the outdoor unit 2 of the heat pump water heater performs the condensation prevention operation only under the condition that condensation is likely to occur. Therefore, the outdoor unit 2 of the heat pump water heater can prevent power consumption from increasing.
Conventionally, when the outdoor temperature is relatively high in summer, the heat sink 15 is cooled down to cause dew condensation on the power elements 16 when the water heating process is completed, but when the outdoor temperature approaches 0 ℃ in winter, dew condensation on the power elements 16 is less likely to occur even when the water heating process is completed and the heat sink 15 is cooled down. That is, the dew condensation preventing operation is required in summer, and is not required in winter. The outdoor unit 2 of the heat pump water heater performs the condensation prevention operation only under the condition that condensation is likely to occur.
Embodiment mode 2
Next, the outdoor unit 2 of the heat pump water heater according to embodiment 2 will be described. The configuration of the outdoor unit 2 of the heat pump water heater according to embodiment 2 is the same as the configuration of the outdoor unit 2 of the heat pump water heater according to embodiment 1. In embodiment 1, when the water heating process is completed, the controller 23 drives the compressor 10 to open the expansion valve 11 and rotate the fan 8 in the same direction as the rotation direction of the fan 8 when heating the water.
In embodiment 2, when the water heating process is completed, the controller 23 rotates the fan 8 in the direction opposite to the rotation direction of the fan 8 when the water is heated. That is, when the water heating process is completed, the control unit 23 causes the motor 9 to drive the fan 8 in a direction opposite to the rotation direction of the fan 8 when the water is heated.
Next, the operation of the outdoor unit 2 of the heat pump water heater according to embodiment 2 will be described. Fig. 8 is a flowchart showing a procedure of the operation of the outdoor unit 2 of the heat pump water heater according to embodiment 2. The operation of the dew condensation preventing operation will be described below.
The outside air temperature detection sensor 14 detects the outside air temperature (S11). When the communication unit 21 receives an operation end signal as a signal indicating that the process of heating water has been completed from the communication unit 31 of the hot water tank unit 3, the control unit 23 determines whether or not the outdoor unit 2 has an outside air temperature higher than the 1 st reference temperature that is a reference for starting the dew condensation prevention operation (S12). When it is determined that the outdoor air temperature of the outdoor unit 2 is equal to or lower than the 1 st reference temperature that is a reference for starting the dew condensation prevention operation (no in S12), the control unit 23 does not perform the dew condensation prevention operation.
When the controller 23 determines that the outdoor air temperature of the outdoor unit 2 is higher than the 1 st reference temperature that is a reference for starting the dew condensation prevention operation (yes at S12), the controller 23 rotates the fan 8 in a direction opposite to the rotation direction of the fan 8 when heating water (S13). By the operation of step S13, the air outside the outdoor unit 2 reaches the heat sink 15 without passing through the air heat exchanger 7.
Fig. 9 is a cross-sectional view illustrating the outdoor unit 2 of the heat pump water heater according to embodiment 2 when the outdoor unit 2 is viewed from one side surface side of the outdoor unit 2 of the heat pump water heater according to embodiment 2. The structure shown in fig. 9 is the same as the structure shown in fig. 2. The arrows in fig. 9 indicate that the wind generated by the rotation of the fan 8 moves from the air heat exchanger 7 toward the fan 8. As is clear from a comparison between fig. 2 according to embodiment 1 and fig. 9 according to embodiment 2, the direction of the wind generated by the rotation of the fan 8 in embodiment 2 is substantially opposite to the direction of the wind generated by the rotation of the fan 8 in embodiment 1. That is, by the operation of step S13, the air outside the outdoor unit 2 reaches the heat sink 15 without passing through the air heat exchanger 7.
The exchanger temperature detection sensor 13 detects the temperature of the air heat exchanger 7 (S14). The control unit 23 determines whether or not the difference between the temperature of the air heat exchanger 7 and the outside air temperature after the water heating process is completed is equal to or less than a predetermined value (S15). Information indicating a predetermined value is stored in the memory 22. If the control unit 23 determines that the difference is larger than the predetermined value (no in S15), the operation of the outdoor unit 2 proceeds to step S14. If it is determined that the difference is equal to or less than the predetermined value (yes in S15), the controller 23 stops the operation of the fan 8 after a predetermined time has elapsed from when it is determined that the difference is equal to or less than the predetermined value (S16). That is, in step S16, the control unit 23 stops the operation of the fan 8 after a predetermined time has elapsed from when it is determined that the difference is equal to or less than a predetermined value.
As described above, when the water heating process is completed, the control unit 23 of the outdoor unit 2 rotates the fan 8 in the direction opposite to the rotation direction of the fan 8 when the water is heated. When the fan 8 is rotated in a direction opposite to the rotation direction when heating water, the air outside the outdoor unit 2 can reach the heat sink 15 without passing through the air heat exchanger 7. As described above, the dew condensation preventing operation is required in summer, but is not required in winter. Therefore, when the fan 8 is rotated in the direction opposite to the rotation direction when heating water, relatively high-temperature air can be caused to reach the heat sink 15 from the outside of the outdoor unit 2, and dew condensation on the power elements 16 can be suppressed.
As described above, the control unit 23 stops the dew condensation preventing operation when a certain time period, which can be determined that the heat sink 15 has been sufficiently warmed up, has elapsed after the start of the dew condensation preventing operation, as in embodiment 1. That is, the outdoor unit 2 of the heat pump water heater performs the condensation prevention operation only under the condition that condensation is likely to occur, and thus, it is possible to prevent an increase in power consumption.
The following may be configured: when the water heating process is completed, the outdoor unit 2 of the heat pump water heater performs the condensation prevention operation of embodiment 1 when the outside air temperature of the outdoor unit 2 is equal to or higher than a predetermined temperature, and performs the condensation prevention operation of embodiment 2 when the outside air temperature of the outdoor unit 2 is lower than the predetermined temperature.
Fig. 10 is a diagram showing a processing circuit 91 in a case where at least some of the components constituting the outdoor unit 2 of the heat pump water heaters according to embodiments 1 and 2 are realized by the processing circuit 91, the communication unit 21, the control unit 23, the temperature acquisition unit 24, the motor drive circuit 25, the compressor drive circuit 26, the expansion valve drive circuit 27, and the timer 28. That is, the following configuration may be adopted: at least a part of the functions of the communication unit 21, the control unit 23, the temperature acquisition unit 24, the motor drive circuit 25, the compressor drive circuit 26, the expansion valve drive circuit 27, and the timer 28 is realized by the processing circuit 91.
The processing circuit 91 is dedicated hardware. That is, the processing Circuit 91 is, for example, a single Circuit, a composite Circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a Circuit in which these are combined. The following may be configured: some of the communication unit 21, the control unit 23, the temperature acquisition unit 24, the motor drive circuit 25, the compressor drive circuit 26, the expansion valve drive circuit 27, and the timer 28 are dedicated hardware separate from the rest.
Fig. 11 is a diagram showing the processor 93 in a case where at least a part of the functions of the communication unit 21, the control unit 23, the temperature acquisition unit 24, the motor drive circuit 25, the compressor drive circuit 26, the expansion valve drive circuit 27, and the timer 28 of the outdoor unit 2 of the heat pump water heater according to embodiment 1 and embodiment 2 is realized by the processor 93. That is, the following configuration may be adopted: at least a part of the functions of the communication unit 21, the control unit 23, the temperature acquisition unit 24, the motor drive circuit 25, the compressor drive circuit 26, the expansion valve drive circuit 27, and the timer 28 are realized by the processor 93 executing a program stored in the memory 92. The Processor 93 is a CPU (Central Processing Unit), a Processing device, an arithmetic device, a microprocessor, a microcomputer, or a DSP (Digital Signal Processor). In fig. 11, a memory 92 is also shown.
When at least a part of the functions of the communication unit 21, the control unit 23, the temperature acquisition unit 24, the motor drive circuit 25, the compressor drive circuit 26, the expansion valve drive circuit 27, and the timer 28 is realized by the processor 93, the part of the functions is realized by the processor 93, software, firmware, or a combination of software and firmware. The software or firmware is described as a program and stored in the memory 92. The processor 93 reads and executes the program stored in the memory 92, thereby realizing at least a part of the functions of the communication unit 21, the control unit 23, the temperature acquisition unit 24, the motor drive circuit 25, the compressor drive circuit 26, the expansion valve drive circuit 27, and the timer 28.
That is, when at least a part of the functions of the communication unit 21, the control unit 23, the temperature acquisition unit 24, the motor drive circuit 25, the compressor drive circuit 26, the expansion valve drive circuit 27, and the timer 28 is realized by the processor 93, the outdoor unit 2 includes the memory 92 for storing a program that, as a result, executes a step executed by at least a part of the communication unit 21, the control unit 23, the temperature acquisition unit 24, the motor drive circuit 25, the compressor drive circuit 26, the expansion valve drive circuit 27, and the timer 28. The program stored in the memory 92 may be a program for causing a computer to execute a procedure or a method executed by at least a part of the communication unit 21, the control unit 23, the temperature acquisition unit 24, the motor drive circuit 25, the compressor drive circuit 26, the expansion valve drive circuit 27, and the timer 28.
Examples of the Memory 92 include nonvolatile or volatile semiconductor memories such as RAM (Random Access Memory), ROM (Read Only Memory), flash Memory, EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically Erasable Programmable Read Only Memory), and the like, magnetic disks, floppy disks, optical disks, mini-optical disks, and DVD (Digital Versatile Disk).
A part of the plurality of functions of the communication unit 21, the control unit 23, the temperature acquisition unit 24, the motor drive circuit 25, the compressor drive circuit 26, the expansion valve drive circuit 27, and the timer 28 may be realized by dedicated hardware, and the remaining part of the plurality of functions may be realized by software or firmware. As described above, the functions of the communication unit 21, the control unit 23, the temperature acquisition unit 24, the motor drive circuit 25, the compressor drive circuit 26, the expansion valve drive circuit 27, and the timer 28 can be realized by hardware, software, firmware, or a combination thereof.
The configuration described in the above embodiment is an example of the contents of the present invention, and may be combined with other known techniques, and a part of the configuration may be omitted or modified within a range not departing from the gist of the present invention.
Description of the reference numerals
1 … heat pump water heater; 2 … outdoor unit of heat pump water heater; 3 … water heater tank unit; 4 … water heat exchanger; 5 … inflow tube; 6 … outflow tube; 7 … air heat exchanger; 8 … fan; 9 … a motor; 10 … compressor; 11 … expansion valve; 12 … refrigerant circuit; 13 … exchanger temperature detection sensor; 14 … outside air temperature detecting sensor; 15 … heat sink; 16 … power elements; 16a … 1 st power element unit; 16b … 2 nd power element unit; 16x … cut No. 1; 16y … cut No. 2; 16z, 17a … pore; 17 … control substrate; 18a … bolt No. 1; 18b … bolt No. 2; 18c … bolt No. 3; 21. 31 … a communication part; 22. 92 … memory; 23 … control unit; 24 … temperature acquisition unit; 25 … motor drive circuit; 26 … compressor drive circuit; 27 … expansion valve drive circuit; 28 … timer; 41 … passages for air; 42 … space; 91 … processing circuitry; 93 … processor.

Claims (1)

1. An outdoor unit of a heat pump water heater, comprising:
an air heat exchanger for performing heat exchange between air outside the outdoor unit and the refrigerant;
a compressor capable of compressing the refrigerant flowing out of the air heat exchanger;
a water heat exchanger that exchanges heat between the refrigerant flowing out of the compressor and water;
an expansion valve capable of reducing the pressure of the refrigerant flowing out of the water heat exchanger;
a fan that moves air outside the outdoor unit to the air heat exchanger;
a motor that rotates the fan;
a power element for driving the compressor, the expansion valve, and the motor;
a heat sink located in a space in which a passage of air moving from outside the outdoor unit to the air heat exchanger by rotation of the fan is extended across the air heat exchanger when the water is heated, and dissipating heat generated from the power element when the compressor is driven; and
and a control unit that, when the water heating process is completed and the control unit determines that the outdoor air temperature of the outdoor unit is higher than a 1 st reference temperature that is a reference for starting the dew condensation prevention operation, rotates the fan in a direction opposite to a rotation direction of the fan when the water is heated.
CN201780089153.XA 2017-04-04 2017-04-04 Outdoor unit of heat pump type water heater Expired - Fee Related CN110494699B (en)

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US20200191435A1 (en) 2020-06-18
JPWO2018185826A1 (en) 2019-06-27
JP6689452B2 (en) 2020-04-28
EP3608602A1 (en) 2020-02-12
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WO2018185826A1 (en) 2018-10-11
EP3608602A4 (en) 2020-03-25

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