JP4284304B2 - Heat pump water heater, operating method thereof, refrigeration cycle apparatus - Google Patents

Description

  The present invention relates to a heat pump water heater, and more particularly to improvement of start-up characteristics at the start of operation in an instantaneous type.

  A conventional heat pump water heater has a large capacity hot water storage tank of 300 to 500L like an electric water heater, and heat pump operation is performed at night using inexpensive electric power at night, and water is boiled and stored in the hot water storage tank. In addition, a hot water storage type in which the hot water in the hot water storage tank is used during the day is common.

  In recent years, with the aim of reducing the size and weight of the hot water storage tank and saving energy, a momentary system has been proposed in which heat pump operation is performed whenever hot water is used, and hot water heated by a water-refrigerant heat exchanger is directly discharged and supplied to the terminal used. ing.

  As such an instantaneous heat pump water heater, a tankless instantaneous type having no hot water storage tank disclosed in Japanese Patent Laid-Open No. 2003-240344 (Patent Document 1) and Japanese Patent Laid-Open No. 2003-240339 (Patent) Document 2) and Japanese Patent Application Laid-Open No. 2003-279133 (Patent Document 3) have proposed an instantaneous type with a tank having a hot water storage tank.

JP 2003-240344 A JP 2003-240339 A JP 2003-279133 A

  In the instantaneous heat pump water heater without a hot water storage tank as in Patent Document 1, since there is no hot water storage tank, it can be greatly reduced in size and weight. However, the start-up characteristics, that is, the proper temperature (about 40 after the faucet is opened and the use of the water supply is started). It takes several minutes to reach (° C.) and is not suitable for hand-washing and dishwashing, which can be done in a relatively short time.

  According to the instantaneous heat pump water heater with a hot water storage tank as in Patent Documents 2 and 3, the hot water in the hot water storage tank (about 60 to 90 ° C.) is added to the water that has not reached the appropriate temperature at the start of operation (for example, 20 to 30 ° C.). Since the hot water can be supplied from the faucet at a suitable temperature, it can be considered that the start-up characteristics have been improved from the user's point of view.

  However, if the hot water is discharged from the hot water storage tank, heat is radiated from the hot water storage tank, which is not preferable from the viewpoint of heating efficiency (daily average COP or annual average COP). Therefore, it is necessary to suppress the amount of hot water discharged from the hot water storage tank so as not to reduce the heating efficiency as much as possible. To do so, it is necessary to quickly establish an instantaneous path for hot water directly from the water-refrigerant heat exchanger.

  An object of the present invention is to shorten the rise time in an instantaneous heat pump water heater.

  The object of the present invention is achieved by first operating the compressor for a short period of time at the start of operation, once stopping and then performing the main operation.

  According to the present invention, the operation start-up time of the compressor can be shortened. Further, if the water heater has a hot water storage tank, the amount of hot water discharged from the hot water storage tank at the start of operation can be suppressed.

  Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

  In FIG. 1, the component configuration and the function of each component will be described. The heat pump water heater includes a heat pump refrigerant circuit 30, a hot water supply circuit 40, and operation control means 50. The heat pump refrigerant circuit 30 and the hot water supply circuit 40 are integrally stored in the same box. The operation control means 50 is a part related to an electric signal, and signals are input from the kitchen remote controller 51 and the bath remote controller 52 (provided separately from the box), and further from each remote controller / sensor. It comprises a control unit (disposed in the box but not shown) that calculates and outputs control signals such as the rotational speeds 1a and 1b, the opening and closing of each valve, and the operation of the pump.

  The heat pump refrigerant circuit 30 is a two-cycle system of a refrigerant circuit A30a and a refrigerant circuit B30b, and has two main parts, and is disposed in the compressors 1a and 1b, the refrigerant on-off valve A2, and the water refrigerant heat exchanger 3. The refrigerant side heat transfer pipes 3a and 3b, the refrigerant on-off valve B4, the bath refrigerant pipe 5a disposed in the bath heat exchanger 5, the refrigerant adjustment valves 6a and 6b, and the evaporators 7a and 7b are sequentially supplied via refrigerant pipes, respectively. It is configured to be connected, and a refrigerant is enclosed therein. This refrigerant is preferably CO2, and the refrigeration cycle at this time is a supercritical cycle in which the high pressure side is operated in a supercritical state of CO2.

  The compressors 1a and 1b are scroll compressors that have a large capacity that can be adapted to an instantaneous heat pump water heater and that can change the number of rotations according to the amount of hot water. That is, the rotation speed of the compressors 1a and 1b is controlled from low speed (for example, 700 rotations / minute) to high speed (for example, 7,000 rotations / minute) by PWM control, voltage control (for example, PAM control) and combination control thereof. It is like that.

  The water refrigerant heat exchanger 3 includes refrigerant side heat transfer tubes 3a and 3b and water supply side heat transfer tubes 3c and 3d, and performs heat exchange between the refrigerant side heat transfer tubes 3a and 3b and the water supply side heat transfer tubes 3c and 3d. Configured to do.

  As the refrigerant adjustment valves 6a and 6b, capillaries, temperature type expansion valves, electric expansion valves and the like are generally used. The refrigerant regulating valves 6a and 6b serve as a pressure reducing device that depressurizes the medium-temperature high-pressure refrigerant sent through the water-refrigerant heat exchanger 3 and sends it to the evaporators 7a and 7b as a low-pressure refrigerant that easily evaporates. Also, the function of adjusting the refrigerant circulation amount in the heat pump circuit by changing the throttle amount of the refrigerant passage, and the function of the defrosting device that melts frost by fully opening the throttle amount and sending a large amount of medium temperature refrigerant to the evaporators 7a and 7b. Is also responsible.

  As the refrigerant adjustment valves 6a and 6b, an electric expansion valve or an electromagnetic two-way valve having a quick response speed to the opening / closing instruction signal from the operation control means 50 is suitable. In addition, when using an electromagnetic two-way valve as the refrigerant regulating valves 6a and 6b, a capillary tube for controlling the pressure reduction of the refrigerant is required together with the electromagnetic two-way valve for opening and closing the refrigerant.

  The evaporators 7a and 7b are air refrigerant heat exchangers that exchange heat between air and refrigerant. Heat can be efficiently exchanged by using a fan (not shown). Reference numerals 8a and 8b denote pressure sensors, which detect the discharge pressure (Pd ′), which is the high-pressure side pressure of the compressors 1a and 1b, send a signal to the operation control means 50, and supply the rotation speed of the compressor and the evaporators 7a and 7b. For controlling the rotational speed of a fan motor (not shown) for controlling the air volume. Note that the suction pressure (Ps ′), which is the low-pressure side pressure, may be detected by the temperature of the evaporator thermistors 7c and 7d attached to the evaporators 7a and 7b, instead of the pressure sensor 8, and substituted for the suction pressure. I can do it.

  Further, the pressure reducing valve 10 controls, for example, a high water pressure with a variation of 200 to 500 kPa supplied from a water supply source to a constant water pressure suitable for use of about 170 kPa. Water flows only in one direction to prevent backflow.

  The hot water supply circuit 40 includes a water circulation circuit for performing faucet hot water supply, bath hot water supply, tank boiling back, and bath reheating.

  The kitchen faucet hot water supply circuit includes a water supply fitting 9, a pressure reducing valve 10, a water supply amount sensor 11, a water check valve 12, a water supply side heat transfer pipe 3c, 3d, a tank mixing valve 29, a hot water mixing valve 13, a flow rate adjusting valve 14, and a kitchen hot water. A direct hot water supply circuit (so-called instantaneous path) in which metal fittings 15 are sequentially connected via a water pipe, a water supply metal fitting 9, a pressure reducing valve 10, a water supply water amount sensor 11, a hot water storage tank 27, a tank mixing valve 29, a hot water mixing valve 13, A flow rate adjusting valve 14 and a kitchen hot water fitting 15 are constituted by a tank hot water supply circuit sequentially connected through a water pipe. The water supply fitting 9 is connected to a water supply source such as a water supply, and the kitchen tap metal fitting 15 is connected to the kitchen faucet 16 and the bath faucet 25.

  The bath hot water supply circuit includes a water supply fitting 9, a pressure reducing valve 10, a water supply amount sensor 11, a water check valve 12, a water supply side heat transfer pipe 3c, 3d, a tank mixing valve 29, a hot water mixing valve 13, a flow rate adjusting valve 14, and a bath pouring bath. A valve 17, a flow switch 18, a bath circulation pump 19, a water level sensor 20, a hot water supply circuit for baths in which a metal inlet / outlet fitting 21 is sequentially connected via a water pipe, a water supply fitting 9, a pressure reducing valve 10, a water supply water amount sensor 11, A hot water storage tank 27, a tank mixing valve 29, a hot water mixing valve 13, a flow rate adjusting valve 14, a bath pouring valve 17, a flow switch 18, a bath circulation pump 19, a water level sensor 20, and a hot water inlet / outlet fitting 21 are sequentially connected through a water pipe. The bath tank hot water supply circuit is configured.

  The tank boiling back circuit is configured by sequentially connecting a hot water storage tank 27, an in-machine circulation pump 28, water supply side heat transfer tubes 3c and 3d, a tank mixing valve 29, and a hot water storage tank 27 via a water pipe. During the tank boiling back operation, the in-machine circulation pump 28 is operated together with the heat pump operation, the water in the hot water storage tank 27 is taken out from the lower part and circulated, heated by the water supply side heat transfer tubes 3c and 3d, and then into the hot water storage tank 27. It is returned from the upper side and heated up sequentially. Reference numerals 27a to 27d are temperature detection thermistors attached to the side surface of the hot water storage tank 27, and are used to detect the amount of hot water storage and / or the amount of hot water used by dividing the hot water storage tank 27 into upper and lower portions.

  The bath reheating circuit has a structure in which an incoming / outgoing hot water fitting 21, a water level sensor 20, a bath circulation pump 19, a flow switch 18, a bath water pipe 5b of the bath heat exchanger 5, and a bath hot water fitting 24 are sequentially connected via a water pipe. Has been. The hot water fitting 21 is connected to the bathtub 23 via a bath circulation adapter 22 to supply hot water from the water level sensor 20 side to the bathtub 23 during bath hot water supply, and to circulate water from the bathtub 23 side to the water level sensor 20 side during bath replenishment. It is configured as follows. Further, when bathing, the water circulation pump 19 is operated to circulate water in the bath water by the bath chasing circuit, the heat pump operation is performed, the refrigerant on-off valve A2 is closed, and the refrigerant on-off valve B4 is opened to open the bath refrigerant. A high temperature refrigerant is circulated in the pipe 5a, and the remaining hot water in the bathtub 23 circulating in the bath water pipe 5b is heated and returned to the bathtub 23 to perform bath renewal.

  In addition to the evaporator thermistors 7c and 7d and the pressure sensors 8a and 8b, the heat pump water heater includes a water supply thermistor 11a that detects the temperature of the water supply, a heat exchanger thermistor 3e that detects the temperature of the hot water of the water-refrigerant heat exchanger 3, and a hot water supply temperature. The hot water supply thermistor 13a for detecting the water level, the water level sensor 20 for detecting the water level in the bathtub 23, and the like are provided, and each detection signal is input to the operation control means 50.

  The operation control means 50 controls each device based on these signals. That is, depending on the operation settings of the kitchen remote controller 51 and the bath remote controller 52, operation / stop of the heat pump refrigerant circuit 30, control of the rotation speed of the compressors 1a, 1b, opening / closing of the refrigerant on / off valve A2, refrigerant on / off valve B4, refrigerant adjusting valve 6a, By adjusting the refrigerant throttle amount adjustment of 6b, the operation / stop of the bath circulation pump 19, and the hot water mixing valve 13, the flow rate adjusting valve 14, the bath pouring valve 17, the flow switch 18 and the like, direct hot water supply operation, bath hot water filling operation And bath memorial operation. Further, the operation control means 50 performs two-stage start control described later, and at the start of operation, the main operation is performed after the compressors 1a and 1b are preliminarily operated.

  Next, the operation of the heat pump water heater will be described based on FIGS. 2 to 12 (excluding FIG. 7) with reference to the heat pump circuit 30 and the hot water supply circuit 40 of FIG.

First, the configuration and compression operation of the compressor will be described with reference to FIGS.
FIG. 2 shows a refrigeration cycle including the scroll compressor 1a, and is a diagram showing an outline of the refrigerant pressure particularly in the chamber of the compressor 1a. The inside of the chamber of the scroll compressor 1b is the same as that in FIG.

  FIG. 3 is a diagram for explaining the configuration of the compression chamber 103, the back pressure chamber 123, and the like of FIG. Sectional drawing etc. are demonstrated in FIGS. 8-12 using the compressor for heat pump water heaters.

  FIG. 8 is a longitudinal sectional view of the horizontal scroll compressor according to the first embodiment of the present invention. FIG. 8 is a diagram showing a plurality of sections of the orbiting scroll, the fixed scroll, the frame, and the Oldham ring. FIG. 10 is a cross-sectional view taken along the line AA of FIG. 8 when the fixed scroll is viewed from the scroll wrap side, and FIG. 10 is an enlarged view of the differential pressure control valve 108.

First, the structure will be described. In FIG. 8, the orbiting scroll 101 has a scroll wrap 101b standing on an end plate 101a, and a bearing holding portion 101d into which an orbiting bearing 101c is inserted and an orbiting Oldham groove 101e. As shown in FIG. 9, the fixed scroll 102 is provided with a non-turning reference surface 102a which is the same surface as the scroll wrap tooth tip surface, and a peripheral groove 102b is formed there.
Then, four bypass holes 102c are provided in the tooth bottom. The reason why the bypass hole 102c is provided here is to extract the refrigerant gas from the bypass hole 102c when the pressure in the compression chamber 103 becomes equal to or higher than the discharge pressure. In FIG. 8, a bypass valve plate 104 that is a reed valve plate and a retainer 104 a that limits the degree of opening of the valve plate 104 are fixed by a bypass screw 105 so as to cover the bypass hole 102 c. A discharge hole 102d is opened near the center.

Moreover, in FIG. 9, the suction digging 102e is provided in the outer edge side of a tooth base, and the suction hole 102f for inserting the suction pipe 106 from there is provided there. The suction pipe 106 is inserted into the suction hole 102f. At this time, the valve body 107a and the check valve spring 107b are inserted to form the suction side check valve 107. Further, a plurality of flow grooves 102 g for flowing the discharge gas and oil are provided on the outer periphery of the fixed scroll 102.
9 and 10, the valve hole 102h is opened to provide a valve seal surface 102i. A suction-side conduction path 102k that communicates with the R groove 102m from the side surface of the valve hole 102h is provided. In FIG. 10, the valve cap 108d has a diameter larger than that of the valve hole 102h in a state where the valve body 108a and the differential pressure valve spring 108b are inserted into the valve hole 102h, and one end of the differential pressure valve spring 108b is inserted into the spring positioning tool 108c. A pressure difference control valve 108 is formed by press-fitting into the large valve cap insertion portion 102l.

  The frame 109 is provided with a fixed mounting surface 109a for mounting the fixed scroll 102 on the outer peripheral portion, and a turning pinching surface 109b on the inner side. Further on the inner side, a frame Oldham groove 109 c is provided in order to place the Oldham ring 110 between the frame 109 and the orbiting scroll 101. A shaft seal 109d and a main bearing 109e are provided at the center, and a shaft thrust surface 109f for receiving the shaft 111 is provided on the scroll side. A plurality of flow grooves 109h serving as gas and oil flow paths are provided on the outer peripheral surface.

  A frame protrusion 110a is provided on one surface of the Oldham ring 110, and a turning protrusion 110b is provided on the other surface.

  The shaft 111 is provided with a shaft oil supply hole 111a, a main bearing oil supply hole 111b, a shaft seal oil supply hole 111c, and a sub-bearing oil supply hole 111d. Further, the pivot bearing 101c is inserted into the eccentric portion 111e, and the auxiliary bearing 113 is inserted into one end portion. The auxiliary bearing 113 is incorporated in the auxiliary shaft housing 115, and the auxiliary shaft housing 115 is fixed to the auxiliary bearing support plate 114 fixed to the sealed container 122. Further, a rotor 112 a is press-fitted into the shaft 111, and a motor 112 is formed with a stator 112 b that is shrink-fitted into the sealed container 122.

  Next, the operation will be described. As the rotor 112a rotates, the shaft 111 rotates and the orbiting scroll 101 orbits. Here, since the Oldham ring 110 is provided, rotation of the orbiting scroll 101 is prevented. By this operation, the refrigerant gas in the suction port 116 enters the compression chamber 103 formed between the scrolls and is compressed and discharged from the discharge hole 102d to the fixed back chamber 117. The pressure at this time is Pd.

  The refrigerant gas discharged into the fixed back chamber 117 enters the motor chamber 118 through the fixed scroll 102 and flow grooves 102g and 109h in the outer periphery of the frame. The refrigerant gas that has entered the motor chamber 118 passes through the motor 112. In the process, the refrigerant gas collides with the rotor 112 a and the stator 112 b and separates the oil contained therein, and the separated oil falls in the lower part of the motor chamber 118. The refrigerant gas that has entered the motor chamber 118 passes through the vent hole 114a formed in the auxiliary shaft support plate 114, collides with the oil separation plate 125, separates the oil contained therein, and exits from the discharge pipe 120 to the outside.

  Here, the refrigerant gas is throttled by the flow path resistance passing through the vent hole 114a, and the pressure in the oil storage chamber 121 is lower than the pressure in the motor chamber 118 and becomes Pd '. As a result, the lubricating oil 119 in the motor chamber 118 is pushed out from the oil guide hole 114 b of the auxiliary shaft support plate 114, and the oil level in the oil storage chamber 121 becomes higher than the oil level in the motor chamber 118.

  Next, refueling will be described. The pressure in the intermediate pressure chamber 123 formed by the orbiting scroll 101, the fixed scroll 102, and the frame 109 is a pressure between the suction pressure Ps and the discharge pressure Pd by the differential pressure control valve 108 (hereinafter referred to as intermediate pressure Pb). Become. The lubricating oil 119 in the oil storage chamber 121 in the discharge pressure atmosphere is supplied from the oil supply pipe 124 to the swivel bearing 101c through the shaft oil supply hole 111a due to the differential pressure between the discharge pressure Pd 'and the intermediate pressure Pb.

  Further, the sliding force is supplied from the main bearing oil supply hole 111b, the shaft seal oil supply hole 111c, and the sub-bearing oil supply hole 111d to the sliding portions by the centrifugal force generated by the rotation of the shaft 111. The lubricating oil 119 supplied to the slewing bearing 101 c leaks into the intermediate pressure chamber 123, enters the suction port 116 from the differential pressure control valve 108, and is discharged to the fixed back chamber 117 together with the refrigerant gas.

  Next, each chamber and pressure will be described.

  The suction chamber 116 is mainly formed by the orbiting scroll 101 and the fixed scroll 102, is in a pressure state of the suction pressure Ps, and is connected to the evaporator 7 a via the check valve 107. The pressure from the check valve 107 to the inlet of the compression chamber 103 is also considered as the suction pressure. In that sense, it can be said to be a low pressure Ps with respect to a high pressure Pd described later.

  The compression chamber 103 is mainly formed by the orbiting scroll 101 and the fixed scroll 102. The compression chamber 103 compresses the refrigerant from the low pressure Ps to the high pressure Pd by the rotational movement of the shaft 111. The central portion communicates with the inside of the compressor chamber (the upper side in FIG. 3 and the fixed back chamber 117 in FIG. 8) on the discharge side. Pd is the discharge pressure, that is, the pressure of the refrigerant discharged from the compression chamber 103. Thereafter, the compressor discharge pressure measured by the pressure sensor 8 through 114a is Pd '.

  The back pressure chamber (intermediate pressure chamber) 123 is mainly formed by the orbiting scroll 101 and the frame 109, and the suction chamber 116 is the surface of the end plate 101a (end plate surface) of the orbiting scroll 101 and the fixed scroll 102 facing the same. The lubricant stored in the lower portion of the compressor 1 a communicates with the sandwich thrust (throttle X 1) that is a minute gap between the opposed surfaces and the minute amount between the shaft thrust surface 109 f formed on the shaft 111 and the orbiting scroll 101. The clearance and the shaft 111 communicate with each of the bearings 101c and 109e through a minute clearance (aperture X2).

  The refrigerant that has entered the low-pressure chamber (suction chamber 116) is introduced into the compression chamber 103 and compressed, becomes low-pressure Ps to high-pressure Pd, is discharged through the chamber, and is circulated to the refrigerant on-off valves 2 and 4. That is, the compressor illustrated in FIG. 8 and the like is a high-pressure type compressor in which the chamber inner space has a high pressure Pd. The back pressure chamber 123 becomes an intermediate pressure Pb under the influence of the low pressure Ps of the low pressure chamber 116 via the throttle X1 and the influence of the high pressure Pd of the lubricating oil via the throttle X2. The differential pressure between the intermediate pressure Pb and the low pressure Ps becomes the back pressure ΔP (= Pb−Ps) of the orbiting scroll 101, and the orbiting scroll 101 is brought into close contact with the fixed scroll 102, thereby improving the hermeticity of the compression chamber. . Details will be described later using the left half of FIG.

  Continue to explain the sealing performance of the compression chamber. FIG. 12 shows the end plate surface of the orbiting scroll 101 (the tooth tip surface of the fixed scroll 102). The distance between the end plate surface of the orbiting scroll 101 and the tooth tip surface of the fixed scroll 102 is ideally zero in view of the sealing property of the compression chamber 103, but there is a minute gap mechanically, and the sealing property is It will not be 100%. Accordingly, the suction chamber 116 and the compression chamber 103 communicate with each other through the tooth tips of the scrolls as much as the above-described sandwich clearance exists. This gap is referred to as an aperture X0 (not shown). It can be considered that the diaphragm X0 exists in the trapezoid of the compression chamber 103 in FIG.

  In the above configuration, during operation of the compressors 1a and 1b, the low-pressure refrigerant having the pressure Ps ′ sucked from the evaporators 7a and 7b enters the low-pressure chamber 116 via the check valve 107 and has a pressure Ps substantially equal to Ps ′. It becomes. Ps ′ is the pressure on the evaporator side, and is the pressure from the refrigerant regulating valves 6a, 6b to the check valve 107. When the check valve 107 is open, Ps ′ = Ps. The check valve 107 is closed when the compressor 1a is stopped to prevent the fluid having the discharge pressure Pd from flowing back to the evaporator 7a, but is open when the compressor is in operation. However, after a sufficiently long time has elapsed after the operation is stopped, the check valve 107 is opened because the pressure in each chamber is balanced.

  During the compressor operation, the lubricating oil that has leaked into the intermediate pressure chamber 123 via the throttle X2 is supplied to the suction chamber 116 via the throttle X1, and is supplied to the compression chamber 103 via the throttle X0. At this time, the sealing oil of the compression chamber 103 is improved by sealing the throttle X0 portion with the lubricating oil. That is, during operation of the compressor, the lubricating oil continues to be supplied to the throttle X0 portion, so that the compression chamber 103 is kept hermetically sealed. However, when the compressor is stopped, the supply of lubricating oil stops and the throttle X0 portion is sealed. Since the action is lost, the compression chamber 103 and the suction chamber 116 communicate with each other and are balanced at the same pressure. This effect is illustrated in FIG.

  12 is a cross-sectional view taken along arrow AA in FIG. Therefore, the tooth tip of the fixed scroll 102 and the tooth bottom of the orbiting scroll 101 are displayed on the paper surface. The tooth bottom is hatched because it has a cross section, but the tooth tip is not hatched because it is real. In FIG. 12, the orbiting scroll 101 that has been hatched rotates counterclockwise. The reason that the high-pressure Pd refrigerant leaks because the sealing action of the restrictor X0 portion is lost is that it leaks outward from the toothed portion of the fixed scroll without hatching on the paper surface of FIG.

  At this time, the high-pressure Pd refrigerant leaks into the suction chamber 116 via X0, and the low-pressure Ps increases to almost Pd due to the influence of Pd. Looking at the relationship between the chambers, the suction chamber 116 and the compression chamber 103 are considered to have the same volume. However, when attention is paid to the pressure, the compressor is a high-pressure type compressor, so that the suction chamber 116 is a space of low pressure Ps. This is because the space of the high pressure Pd is much larger. The space of the high pressure Pd is a total of at least the compression chamber 103, the fixed back chamber 117, and the motor chamber 118.

  As described above, when the operation of the compressor stops, the pressure in the suction chamber 116 also becomes Pd. Further, since the suction chamber 116 communicates with the back pressure chamber (intermediate pressure chamber) 123 via the throttle X1, the pressure in the back pressure chamber 123 also increases to Pd. This is because the volume of the back pressure chamber 123 is also considered to be very small compared to the space of the high pressure Pd.

  This operation will be described with reference to FIG. FIG. 11 shows the magnitudes of the orbiting scroll 101 and the fixed scroll 102 and the pressures Pd, Ps, and Pb. The left half shows the pressure during operation of the compressor, and the right half shows the pressure after stopping the compressor operation. Is shown. The reason why the pressure distribution is curved in the left half is that it is a scroll compressor, and the low-pressure refrigerant enters from the larger radius of the rotation axis of the shaft 111, that is, from the outside. This is because the pressure increases as it goes to the axial center, that is, the center.

  During operation of the compressor, the relationship between the downward pressure and the upward pressure in the left half of the figure is designed so that the upward pressure and thus the upward pressing force are large. The orbiting scroll 101 is brought into close contact with the fixed scroll 102 with P (= Pb−Ps), thereby improving the sealing performance of the compression chamber. Also, the sealing chamber is hermetically sealed by lubricating oil.

  However, when the compressor is stopped, the rotational speed decreases although the rotor rotates slightly due to the rotational inertia, and accordingly, the supply of lubricating oil is reduced, and the sealing effect by the lubricating oil is lost. Then, the sealing property of the compression chamber 103 cannot be maintained, and the suction chamber 116 becomes the high pressure Pd. The right half of FIG. 11 and FIG. 12 show the state at this time. FIG. 12 shows how high-pressure refrigerant leaks from the center toward the outside, and FIG. 11 shows that the downward pressure on the right half has increased to the outside compared to the left half. ing. In this pressure state, the downward force is larger than the pressing force of the upward turning scroll. Accordingly, the orbiting scroll is pushed downward, the function of the throttle X1 is reduced, the back pressure chamber 123 also becomes the high pressure Pd, and the upper and lower pressures of the orbiting scroll 101 are balanced by Pd.

  After a sufficiently long time, for example, 30 minutes, after the compressor is stopped, the pressure balance state becomes Pd = Pb = Ps = Pd ′ = Ps ′. At this time, the check valve 107 is opened.

FIG. 4 is an operation explanatory diagram at the start of operation when the present invention is not applied. The horizontal axis indicates the time passage of the heat pump operation, and the vertical axis indicates the hot water supply usage state, for example, opening / closing of the faucet 16, compressor operating state, The open / close state of the internal check valve 107 and the pressure change inside and outside the compressor are shown.
First, in the hot water supply operation state shown at the left end, the intermediate pressure Pb is in the middle of the discharge pressure Pd and the suction pressure Ps, and the differential pressure between the intermediate pressure Pb and the suction pressure Ps, that is, the back pressure ΔP indicates the sealing property of the compression chamber 103. It is a value that can be maintained sufficiently. Further, Ps ≦ Ps ′ is established by the suction action of the compressors 1a and 1b, and the check valve 107 is opened. However, when the operation is stopped, the check valve 107 is closed and Pd, Pb, and Ps gradually increase. In balance, the low pressure Ps increases. Further, when the pressure of the entire heat pump circuit is balanced through the cycle of the compressor, the refrigerant on-off valve, the refrigerant side heat transfer pipe, the refrigerant adjustment valve, and the evaporator of FIG. 1 as time elapses, it is almost Pd = Pb = Ps = Pd ′ = Ps 'And the check valve is opened. In addition, during the Ta where the pressure is balanced, each pressure line on the graph is overlapped and displayed.

  In the state where the check valve 107 is opened, it becomes the same as when the low pressure side internal volume of the compressor, that is, the suction chamber 116 is expanded to "compressor low pressure portion + evaporator internal volume". Even when the low-pressure side refrigerant is sucked, the pressure in the suction chamber 116 does not easily decrease because the internal volume on the low-pressure side is large. For this reason, the decrease in the low-pressure side pressure Ps is slow, and the back pressure ΔP is difficult to increase. That is, the back pressure ΔP (= Pb−Ps) does not increase, and the orbiting scroll 101 does not sufficiently adhere to the fixed scroll 102, so that the sufficient sealing performance of the compression chamber is not ensured and the efficiency is poor, so the heating rise time is delayed. It will be. That is, the operation rise time T1 takes a long time.

  The heating rise time from the start of the heat pump operation until the temperature of the hot water supply by direct hot water through the water / refrigerant heat exchanger 3 reaches the appropriate temperature for use is called the operation rise time, which greatly affects the size of the hot water storage tank 27 and the convenience of using the hot water supply. It is one of the most important indicators in the instantaneous heat pump water heater.

  During the operation start-up time T1, the hot water supply from the water heat exchanger 3 and the tank hot water supply from the hot water storage tank 27 are used together. The longer the T1, the greater the amount of hot water discharged from the tank. Must. Particularly in the instantaneous heat pump water heater, the capacity of the evaporators 7a and 7b is large because it is necessary to increase the heating capacity. Therefore, since the influence of the low-pressure side pressure Ps is large, the incomplete sealing → low-pressure leakage → the intermediate pressure Pb does not increase → the back pressure is insufficient → the incomplete sealing is a vicious cycle, a heating delay due to insufficient compression occurs, and T1 is long.

  Next, FIG. 5 is an operation explanatory diagram at the start of operation showing the first embodiment of the present invention. As in FIG. 4, the horizontal axis shows the time passage of the heat pump operation, the vertical axis shows the hot water usage condition, and the compressor operation. The state, the open / close state of the check valve 107, and the pressure change inside and outside the compressor are shown.

  The hot water supply operation state shown at the left end is the same as FIG. Further, since the check valve 107 is opened during the preliminary operation (preliminary operation) before the main operation shown on the right side of FIG. 5, the compressors 1a and 1b are used as the suction side volumes of the compressors 1a and 1b. Since the volume of the evaporators 7a and 7b is added to the volume of the low-pressure part, the low-pressure side pressure Ps decreases slowly and the back pressure ΔP increases slowly, so that the fixed scroll 102 and the orbiting scroll 101 are not in close contact with each other. Although continuing, preliminary operation stops in a short time T3 of several tens of seconds. As described above, when the preliminary operation stops, both the suction pressure Ps and the intermediate pressure Pb increase to almost Pd. When the preliminary operation of the compressor is stopped, the check valve 107 is closed.

  Even if some time has elapsed after stopping the preliminary operation, the preliminary operation stop time T4 is set so that the main operation is started while the back pressure ΔP is kept sufficiently high. When the operation is resumed after the temporary operation is temporarily stopped for a short time (T3) (the main operation is started), the check valve 107 is first opened. Then, it becomes the same as that the suction chamber 116 was expanded to "compressor low pressure part + evaporator internal volume", and the pressure of the suction chamber 116 should not easily decrease.

  However, the pressure in the suction chamber 116 that has been Pd during the preliminary operation stop time T4 decreases to Ps ′ due to the opening of the check valve 107, and the back pressure ΔP rapidly increases. Although the back pressure ΔP is increased, it is maintained at a predetermined value or less by the differential pressure control valve 108. Due to the increased back pressure ΔP, the fixed scroll 102 is pressed and the sealing with the orbiting scroll 101 is sufficiently sealed, so that the sufficiently compressed high-temperature and high-pressure refrigerant passes through the compressors 1a and 1b to perform water refrigerant heat exchange. It exhales to the container 3 side.

  The operation rise time in FIG. 4 takes a relatively long time as indicated by T1, but when the two-stage start control of the preliminary operation and the main operation is used, the operation rise time is reduced as indicated by T2 in FIG. be able to. The amount of hot water discharged from the hot water storage tank 27 can be suppressed by this time shortening. Since the end of T2 is the time at which the hot water from the hot water storage tank can be stopped, it is not preferable in terms of clarifying the end of T2. Further, it is considered that the period from the start of the actual operation to the end of T2 is relatively short. Therefore, the amount of hot water discharged from the hot water storage tank can be suppressed even if at least the time from when there is a hot water supply request until the actual operation is started is considered. As a result, the tank capacity can be reduced and the size can be reduced substantially in proportion to T2 / T1.

  The preliminary operation time T3 is, for example, about 30 to 40 seconds after which the back pressure ΔP can be secured after the operation is stopped due to the pressure change of Pd and Ps. Further, in order to start the main operation within the time during which the back pressure ΔP is secured, the preliminary operation stop time T4 is set to, for example, around 10 to 20 seconds. Of course, these times are preferably as short as possible within a range where the operation start-up time can be shortened.

  Using a total of about 1 minute of the preliminary operation time of 30 to 40 seconds and the preliminary operation stop time of 10 to 20 seconds seems to be a detour, but even if these times are used, the operation start-up time can be shortened. . For example, a conventional one-cycle heat pump that takes about 6 minutes and a two-cycle heat pump that takes about 4 minutes can be shortened to about 3 minutes by performing two-stage start control. In this way, the amount of hot water supply from the hot water storage tank can be reduced, and the release of heat can be reduced, so that the heating capacity can be kept high. Moreover, since the amount of hot water supplied from the hot water storage tank can be suppressed, the hot water storage tank can be miniaturized. In addition, by performing the preliminary operation, lubricating oil is supplied in advance to each sliding portion of the compressor, and it is possible to improve the starting reliability of the compressor corresponding to the acceleration of the rotation speed during the main operation. It also has an effect that can be achieved.

  In this embodiment, considering the acceleration characteristics of the compressor, at the start of operation, the engine is started / operated at medium speed (medium speed operation), and once stopped, the medium speed operation of the compressor is performed within a predetermined time. After that, after the compressor is sufficiently accelerated, it is operated at a high speed (high speed operation) according to the hot water supply temperature and the hot water supply amount. Although the preliminary operation can be performed at a high speed, there is a possibility that the differential pressure becomes too large, and there is a possibility that the preliminary operation stop time needs to be long. Here, the high-speed rotation speed refers to the rotation speed in the steady state of the heat pump water heater, and the medium-speed rotation speed is not more than half of the high-speed rotation speed. Further, the medium speed rotation speed is defined by the largest rotation speed in the preliminary operation.

  The two-stage start control is particularly effective when the stop time Ta of the compressors 1a and 1b is extended over a long time such as 30 minutes or more. This is because the operation is started from a state where Ps and Ps ′ are approximately equal with pressure balance. Further, the check valve 107 is built in the compressor, but this two-stage start control can be applied even if there is a refrigeration cycle arranged outside the compressor.

  Next, FIG. 6 is an example of a flowchart showing the operation when the kitchen faucet 16 is opened and hot water is used. Hereinafter, the two-stage start control including the preliminary operation and the main operation will be mainly described with reference to FIG.

  When there is a hot water supply request, that is, when the kitchen faucet 16 is opened and the use of hot water begins (step 71), the flow rate and temperature of each part are detected by the water supply amount sensor 11, the water supply thermistor 11a, the hot water supply thermistor 13a, etc. Receives an input of the detected value and determines that a hot water supply request has been made. Then, the hot water supply start is determined (step 72). If the flow rate of a certain level or more continues for a predetermined time or longer, it is determined that hot water supply is started, and the operation control means 50 issues an operation start command signal for heat pump operation to each part.

  The reason for the constant flow rate and the constant time is to distinguish between short-time hot water supply use that does not require heat pump operation and continuous hot water use that requires heat pump operation, and to avoid unnecessary heat pump operation. . For example, when a small amount of hand-washing or water is poured into a cup for taking medicine, a hot water supply request is stopped immediately (for example, 3 seconds) even if a large flow rate is requested, so a predetermined time T0 (for example, 5 If the hot water supply request is within a second), the heat pump operation is not performed regardless of the required flow rate. That is, the operation of the compressor is started only when the hot water supply request is continued even after a predetermined time T0 (for example, 5 seconds) since the hot water supply request is made. Also, the heat pump operation is not performed when a small flow rate that can be regarded as water leakage is required.

  The operation control means 50 issues an operation start command, and starts the preliminary operation (step 73) by the two-stage start control, starts the compressors 1a and 1b, and supplies the water supply fitting 9, the pressure reducing valve 10, the water supply water amount sensor 11, Hot water is supplied by the hot water supply circuit of the water check valve 12, the water supply side heat transfer pipes 3 c and 3 d, the tank mixing valve 29, the hot and cold water mixing valve 13, the flow rate adjustment valve 14, the kitchen tap metal 15 and the kitchen faucet 16. (Step 74).

  In the preliminary operation (step 73) after 30 minutes or more after the operation stop, the check valve 107 is opened, the low pressure side capacity is large, and there is no back pressure ΔP, so that the compression chamber 103 is not completely sealed. Yes, the operation start-up time is long, but the preliminary operation (step 73) is stopped in a short time (step 74), and the main operation of the heat pump is started after a predetermined time (step 75). In the main operation (step 75), the back pressure ΔP rapidly increases immediately after the start of the main operation (because it exceeds a certain value α), so that the compression chamber 103 is sufficiently sealed, and the operation rise time is Significantly shortened.

  After the hot water supply is started (step 72), the operation control means 50 adjusts the hot water supply temperature and flow rate based on the detection data of the water supply amount sensor 11, the water supply thermistor 11a, the hot water supply thermistor 13a, etc. (step 75). Continue the hot water supply operation at the flow rate. Note that the hot water temperature and flow rate are always determined (step 76), and if not specified, the hot water temperature and flow rate are adjusted (step 75). If within the specified range, the faucet is closed, that is, the hot water request continues. As long as this is done, hot water supply by direct hot water from the water / refrigerant heat exchanger 3 is continued (step 77). In other words, it is as follows. If the hot water supply request is continued even after the preliminary operation stop time T4 (for example, 10 to 20 seconds) has elapsed after the compressor is temporarily stopped, the operation of the compressor is resumed and the hot water is directly discharged.

  Focusing only on the instantaneous path, high-temperature hot water is not directly discharged from the water-refrigerant heat exchanger 3 immediately after the compressors 1a and 1b start operation, but compression heating of the refrigerant, circulation of the high-temperature refrigerant, and water supply Therefore, cold water from the water supply or warm water that has been warmed up for a while after the kitchen faucet 16 is opened. From the start of the use of the faucet to the time when hot water at the appropriate temperature (about 40 ° C) is directly supplied by the heat pump operation, hot water is supplied by hot water from the hot water storage tank 27 as appropriate, and combined with hot water supply or water supply by direct hot water supply. To supply hot water as the optimal temperature.

  When the kitchen faucet 16 is closed and the use of hot water is completed (step 78), the operation control means 50 stops the compressors 1a and 1b and ends the hot water supply operation (step 79).

  Next, a second embodiment will be described with reference to FIG.

  In contrast to the instantaneous heat pump water heater with a hot water tank described with reference to FIG. 1, the present embodiment uses a two-cycle system and a large capacity compressor, and uses a two-stage start-up control. This is to provide a full-fledged instantaneous heat pump water heater that does not provide

7 has the same configuration from the compressors 1a and 1b to the bath faucet 25 when compared with the heat pump water heater of FIG. 1, and in the hot water supply circuit 40, the hot water storage tank 27, tank thermistors 27a to 27d, and the tank circulation pump 28. In addition, the tank mixing valve 29 is not provided.
In FIG. 7, after first installing the heat pump water heater, the water supply fitting 9, the pressure reducing valve 10, the water supply amount sensor 11, the water check valve 12, the water refrigerant heat exchanger 3, the hot water mixing valve 13, the flow rate adjusting valve 14, the kitchen The water circuit on the kitchen hot water side in the hot water supply device is filled with the water supply circuit of the hot metal fitting 15, and every time the kitchen faucet 16 is opened and hot water is used, the heat pump is operated to supply hot water directly by hot water.

  In this embodiment, the heating capacity of the heat pump water heater is about twice as large as that of the hot water storage tank shown in the first embodiment, and by applying two-stage start control, It can be realized. In other words, the operation start-up time, which previously took about 6 minutes, is reduced to about half by making it 2 cycles, and further reduced to 1 minute or less by applying a large heat pump capacity and two-stage start control. It is intended for practical use.

  When this two-stage start-up control is applied to a conventional hot water storage type heat pump water heater, the hot water storage type operates only once a day at night, so the effect of shortening the heating rise time is small, but the compression is not significant. This improves the compression performance of the machine and has the effect of improving reliability such as prevention of incomplete compression.

  Various variations conceivable in the first embodiment are also effective in the second embodiment.

  The two-stage start control described above is applied to the heat pump water heater, but can also be applied to other refrigeration cycle apparatuses. For example, a showcase installed in an air conditioner, a supermarket, a convenience store, or the like. The heat pump water heater warms the water, but when applied to an air conditioner, a showcase, etc., it cools or warms the air, so the water refrigerant heat exchanger 3 becomes an air refrigerant heat exchanger. There are places where the device configuration must be changed as appropriate. When applied to an air conditioner, there is an effect that a room or the like becomes cooler or warmer than before, and when applied to a showcase, there is an effect that a cooling effect can be obtained immediately. With ON / OFF feedback control using a thermostat, a cooling effect can be obtained immediately each time it is turned on (every time two-stage start control is performed), so that the amount of power can be reduced.

It is a schematic diagram which shows a 1st Example and shows components structure in the case of the instantaneous heat pump water heater with a hot water storage tank. Diagram showing the refrigerant pressure inside the compressor The figure for demonstrating the structure of the compression chamber of a compressor, a back pressure chamber, etc. Operation explanatory diagram when the present invention is not applied Operation explanatory diagram showing the first embodiment of the present invention It is a flowchart which shows an example of the driving | running | working progress at the time of hot water use. It is a schematic diagram which shows a 2nd Example and shows the components structure of the instantaneous heat pump water heater without a hot water storage tank. Longitudinal sectional view of horizontal scroll compressor (view from multiple sections) AA arrow sectional view of FIG. 8 as seen from the scroll wrap side of the fixed scroll Differential pressure control valve enlarged view The figure which shows the magnitude | size of the turning scroll 101, the fixed scroll 102, and pressure Pd, Ps, Pb AA arrow sectional view of FIG.

Explanation of symbols

1a, 1b ... compressor 2 ... refrigerant on-off valve A
3 ... Water refrigerant heat exchangers 3a, 3b ... Refrigerant side heat transfer tubes 3c, 3d ... Water supply side heat transfer tubes 4 ... Refrigerant on-off valve B
DESCRIPTION OF SYMBOLS 5 ... Bath heat exchanger 5a ... Bath refrigerant pipe 5b ... Bath water piping 6a, 6b ... Refrigerant adjustment valve 7a, 7b ... Evaporator 8a, 8b ... Pressure sensor 9 ... Water supply metal fitting 10 ... Pressure reducing valve 11 ... Supply water amount sensor 11a ... Water supply thermistor 12 ... Water check valve 13 ... Hot water mixing valve 13a ... Hot water supply thermistor
14 ... Flow control valve 15 ... Kitchen tap 16 ... Kitchen faucet
17 ... Bath pouring valve 18 ... Flow switch 19 ... Bath circulation pump 20 ... Water level sensor 21 ... Hot water fitting 22 ... Bath circulation adapter 23 ... Bath 24 ... Bath hot water fitting 25 ... Bath faucet 30 ... Heat pump refrigerant circuit 40 ... Hot water supply circuit 50 ... Operation control means 51 ... Kitchen remote control 52 ... Bath remote control 101 ... Orbiting scroll 101a ... End plate 101b ... Scroll wrap 101c ... Orbiting bearing 101d ... Bearing holding part 101e ... Orbiting Oldham groove 102 ... Fixed scroll 102a ... Non-orbiting reference plane 102b ... Circumferential groove 102c ... Bai pie valve 102d ... Discharge hole 102e ... Suction dig 102f ... Suction dig 102g ... Flow groove 102h ... Valve hole 102i ... Valve seal surface 102k ... Suction side conduction path 102l ... Valve cap insertion part 102m ... R groove 103 ... Compression chamber 104 ... Bypass valve plate 104a ... Retainer 105 ... Bypass screw 106 ... Suction pipe 107 ... Suction side check valve 107a ... Valve body 107b ... Check valve spring 108 ... Differential pressure control valve 108a ... Valve body 108b ... Differential pressure valve spring 108c ... Spring positioning protrusion 108d ... Valve cap 109 ... Frame 109a ... Fixed mounting surface 109b ... Swivel pinching surface 109c ... Frame Oldham groove 109d ... Shaft seal 109e ... Main bearing 109f ... Shaft thrust surface 109h ... Flow groove 110 ... Oldham ring 110a ... Frame protrusion 110b ... Rotation protrusion 111 ... shaft 111a ... shaft oil supply hole 111b ... main bearing oil supply hole 111c ... shaft seal oil supply hole 111d ... sub bearing oil supply hole 111e ... eccentric part 112 ... motor 112a ... rotor 112b ... stator 113 ... sub bearing 114 ... sub bearing support plate 114a ... Vent hole 114b ... oil guide hole 115 Countershaft housing 116 ... inlet 117 ... fixed rear chamber 118 ... motor chamber 119 ... lubricant 120 ... discharge pipe 121 ... oil storage chamber 122 ... closed container 123 ... intermediate pressure chamber 124 ... oil supply pipe 125 ... oil separation plate

Claims (14)

A compressor, a water-refrigerant heat exchanger that performs heat exchange between the supplied water and the refrigerant, a refrigerant adjustment valve, and an evaporator that performs heat exchange between the air and the refrigerant are sequentially connected via a refrigerant pipe. A heat pump refrigerant circuit;
A heat pump water heater provided with operation control means for controlling the compressor,
The operation control means operates to operate the compressor for a predetermined short time at the start of operation to perform an operation of sucking refrigerant from the evaporator side and discharging it to the water / refrigerant heat exchanger side, and temporarily stops the compressor within a predetermined time. The heat pump water heater that restarts the operation of sucking the refrigerant from the evaporator side and discharging the refrigerant to the water refrigerant heat exchanger side . The compressor has a fixed scroll, a turning scroll, a check valve, and a frame,
At least a first pressure that is a pressure in the back pressure chamber formed by the orbiting scroll and the frame, and a second pressure that is a pressure in the suction chamber formed by the fixed scroll, the orbiting scroll, and the check valve; The heat pump water heater according to claim 1, which is a scroll type compressor that forms a compression chamber by pressing the orbiting scroll against the fixed scroll with a differential pressure of 2.   2. The heat pump water heater according to claim 1, wherein the time from when the compressor starts operating for a short time to when the compressor is operated within the predetermined time is within one minute. The operation control means controls the rotational speed of the compressor,
At the start of operation, the compressor is operated at a medium speed for a short time, and after stopping, the compressor is operated at a medium speed within a predetermined time, and then at a higher speed,
The heat pump water heater according to claim 1, wherein water heated by the water refrigerant heat exchanger is directly discharged to a use terminal.   The heat pump water heater according to claim 1, further comprising a hot water storage tank for assisting a hot water supply amount to the use terminal until the compressor is operated at least within the predetermined time. A scroll compressor with a built-in check valve, a water refrigerant heat exchanger that exchanges heat between the supplied water and the CO2 refrigerant, an electric expansion valve, and an evaporator that exchanges heat between the atmosphere and the refrigerant, A heat pump refrigerant circuit sequentially connected via a refrigerant pipe;
A hot water storage tank,
When a hot water supply request is made, the operation of sucking the refrigerant from the evaporator side and discharging it to the water / refrigerant heat exchanger side at the start of the operation of the scroll compressor is performed within 40 seconds , and 10 seconds or more have elapsed after the stop. However, when the hot water supply request is continued, the scroll compressor is rotated so as to resume the operation of operating the scroll compressor again to suck the refrigerant from the evaporator side and discharge the refrigerant to the water refrigerant heat exchanger side. Operation control means for controlling the number;
A direct hot water supply circuit for directly discharging the water heated by the water refrigerant heat exchanger to a use terminal;
A tank hot water supply circuit for assisting hot water supply to the use terminal by hot water from the hot water storage tank at least until the operation of the scroll compressor is restarted after the hot water supply request is made;
Having a heat pump water heater. The operation control means includes
The operation of the scroll compressor within 40 seconds is performed at a medium speed, and after stopping once, the operation after resuming operation is performed at a medium speed, and then the speed is changed from a medium speed to a high speed. The heat pump water heater of Claim 6 which controls the rotation speed of the said scroll compressor so that it may raise. In the operation method of the heat pump water heater in which CO2 refrigerant is circulated by controlling the compressor while there is a hot water supply request, and water is heated by the heat exchanger to supply hot water.
When there is a hot water supply request from a state where the compressor is stopped for 30 minutes or more,
The operation of the compressor is started in response to the hot water supply request, the refrigerant is sucked in from the evaporator side and discharged to the water refrigerant heat exchanger side, and the operation is stopped after a predetermined time,
When the hot water supply request is continued even after a predetermined time has elapsed since the operation of the compressor was stopped, the compressor is operated again in accordance with the hot water supply request, and the refrigerant is sucked from the evaporator side. Restart the discharge to the water refrigerant heat exchanger side ,
A method of operating a heat pump water heater that directly discharges water heated by the heat exchanger. The heat pump water heater includes a hot water storage tank for storing hot water,
9. The operation method of a heat pump water heater according to claim 8, wherein hot water supply is assisted by discharging hot water from the hot water storage tank at least from the time when the hot water supply is requested until the compressor operation is restarted. . The time from the start of operation to the stop of the compressor is within 40 seconds,
The operation method of the heat pump water heater according to claim 8, wherein the time from the stoppage of operation of the compressor to the resumption thereof is within 20 seconds.   The operation method of the heat pump water heater according to claim 8, wherein the time from the hot water supply request to the start of operation of the compressor is 5 seconds or more. A refrigeration cycle circuit in which a scroll compressor, a heat exchanger, a refrigerant adjustment valve, and an evaporator are sequentially connected via a pipe;
A refrigeration cycle apparatus comprising operation control means for controlling the compressor,
Said operation control means performs an operation for discharging the refrigerant and briefly driving compressors in predetermined at the time of starting the operation to the evaporator side from the suction and the water-refrigerant heat exchanger side, once after stopping, within a predetermined time A refrigeration cycle apparatus that restarts the operation of operating the compressor again to suck the refrigerant from the evaporator side and discharge the refrigerant to the water refrigerant heat exchanger side . The compressor has a fixed scroll, a turning scroll, a check valve, and a frame,
At least a first pressure that is a pressure in the back pressure chamber formed by the orbiting scroll and the frame, and a second pressure that is a pressure in the suction chamber formed by the fixed scroll, the orbiting scroll, and the check valve; The refrigeration cycle apparatus according to claim 12, which is a scroll type compressor that forms a compression chamber by pressing the orbiting scroll against the fixed scroll with a differential pressure of 15 μm.   The refrigeration cycle apparatus according to claim 12, wherein the time from when the compressor starts operating for a short time to when the compressor is operated within the predetermined time is within one minute.

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