JP2001248937A - Heat pump hot water supply air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat pump hot water supply air conditioner which can utilize the exhaust heat of a refrigerating cycle for indoor cooling and besides can be operated comfortably at indoor cooling hot water storage operation. SOLUTION: This is a heat pump hot water supply air conditioner where a compressor 3, a four-way valve 5, a heat exchanger 6 for water heating for heating water, a flow control valve 8 for an indoor heat exchanger, and an outdoor heat exchanger 9 are connected in series by refrigerant pipes, and besides a flow control valve 10 for an indoor heat exchanger and an indoor heat exchanger 11 are provided in parallel with the flow control valve 8 for outdoor heat exchanger and the outdoor heat exchanger 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump hot water supply air conditioner, and more particularly to a heat pump hot water supply air conditioner capable of controlling a cooling capacity according to a load in a room while a hot water storage capacity is secured.

[0002]

2. Description of the Related Art A conventional heat pump hot water supply air conditioner is shown in FIG.
It has a structure as shown in FIG. The heat pump hot water supply air conditioner 21 has a refrigeration cycle 22, and further sequentially communicates with a compressor 23, a four-way valve 24, a water heating heat exchanger 26 for heating water in a hot water storage tank 25, a throttle device 27, and an outdoor heat exchanger 28. Formed. Such a heat pump hot water supply air conditioner 21 has a water temperature of a hot water storage tank 25 of 30.
If the temperature is lower than ° C, the hot-water storage operation is performed by the heat pump. However, the conventional heat pump hot water supply air conditioner 21
In this method, hot water is supplied using a heat pump, and a separate refrigeration cycle is required for indoor cooling.
For this reason, the exhaust heat of the indoor cooling refrigeration cycle could not be used.

Further, as a heat pump hot water supply air conditioner utilizing exhaust heat of a refrigeration cycle, Japanese Patent Application Laid-Open No. H11-72268.
In the publication, a structure is added in which the water in the hot water supply circuit is heated by the outdoor heat exchanger for heating by the outdoor heat exchanger of the refrigeration cycle and the temperature of the hot water is prevented from decreasing during the defrosting operation of the refrigeration cycle. A disclosed heat pump hot water supply air conditioner is disclosed. As a problem of the heat pump hot water supply air conditioner, the refrigeration cycle is operated in a single operation mode, and thus lacks comfort during indoor cooling hot water storage operation.

[0004]

Therefore, there has been a demand for a heat pump hot water supply air conditioner that can utilize the exhaust heat of the indoor cooling refrigeration cycle and can operate comfortably during the indoor cooling hot water storage operation.

The present invention has been made in view of the above circumstances, and provides a heat pump hot water supply air conditioner which can utilize exhaust heat of a refrigeration cycle for indoor cooling and can operate comfortably during indoor cooling and hot water storage operation. The purpose is to do.

[0006]

Means for Solving the Problems In order to achieve the above object, the invention of claim 1 of the present application is directed to a compressor, a four-way valve, a heat exchanger for heating water, a flow control valve for an outdoor heat exchanger. , An outdoor heat exchanger and the four-way valve are sequentially connected by a refrigerant pipe, and the indoor heat exchanger flow control valve and the indoor heat exchanger are connected to the outdoor heat exchanger flow control valve and the outdoor heat exchanger. The gist is that the heat pump hot water supply air conditioner is provided in parallel with the exchanger.

[0007] In the invention of claim 2 of the present application, the heat pump hot water supply air conditioner has three operation modes of a normal cooling operation, a cooling hot water storage operation, and a hot water storage operation which are switched by a control device. The heat pump hot water supply air conditioner according to claim 1, wherein the heat pump hot water supply air conditioner is selected according to presence / absence and a water temperature in the hot water storage tank.

According to the third aspect of the present invention, when the rotation speed of the compressor is changed according to the operation command frequency from the inverter and the required cooling frequency is low, the compressor frequency is fixed at a predetermined frequency. When the required cooling frequency is high, the air conditioner is varied according to the required cooling frequency from the room, and the heat pump hot water supply air conditioner according to claim 1 or 2 is the gist.

In the fourth aspect of the present invention, in the cooling hot water storage operation mode, the indoor heat exchanger flow control valve is controlled so that the superheat of the indoor heat exchanger is constant.
The gist of the invention is a heat pump hot water supply air conditioner according to claim 2 or 3, wherein the opening degree is controlled in accordance with the required cooling frequency from the room.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a heat pump hot water supply air conditioner according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a heat pump hot water supply air conditioner 1. The heat pump hot water supply air conditioner 1 has a refrigeration cycle 2, and the refrigeration cycle 2 is driven by an inverter 3 so as to be able to control the rotation speed. 4, a four-way valve 5 connected to the discharge side 4 a, a water heating heat exchanger 6, a two-way valve 7, a flow control valve for an outdoor heat exchanger (hereinafter referred to as an outdoor flow control valve) 8, an outdoor heat exchange And a refrigerant pipe connected to the suction side 4b of the compressor 4 via the four-way valve 5 via the four-way valve 5 and a flow control valve for an indoor heat exchanger (hereinafter referred to as an indoor flow control valve) 1
0 and the indoor heat exchanger 11 are provided in parallel with the outdoor flow control valve 8 and the outdoor heat exchanger 9.

The refrigeration cycle 2 is operated by switching the four-way valve 5 to store the hot water by circulating the refrigerant in the direction of the solid line arrow in the drawing, and to operate normally by circulating the refrigerant in the direction of the broken line arrow in the drawing. Has become.

The compressor 4 is connected to an inverter 3 controlled by a control device 12 for controlling the entire heat pump hot water supply air conditioner 1, and the number of revolutions is controlled.
Further, the control device 12 includes a CPU, an input / output interface, a ROM, a RAM, a timer counter, and the like. Based on input signals from various sensors, changeover switches, and the like, the four-way valve 5 and the The driving control of the outdoor flow control valve 8, the indoor flow control valve 10, the outdoor electric fan 9a, the indoor electric fan 11a, and the like is performed.

The heat exchanger 6 for heating water is connected to the water heater 1.
3 is configured to heat water supplied to the hot water storage tank 14 having the water temperature sensor 14 s provided in the hot water storage tank 14 by the amount of heat of the refrigerant. A desired water temperature (hot water temperature) can be achieved by the sensor 14s.

Further, the outdoor flow rate control valve 8 and the indoor flow rate control valve 10 are, for example, motorized control valves whose opening degree is controlled by a pulse generated from the control device 12. It controls the flow rate of the refrigerant flowing through the valve 8 and the indoor flow control valve 10.

The outdoor heat exchanger 9 includes an outdoor electric fan 9.
a and the outdoor-side exchanger sensor 9s, which is installed outdoors and functions as an evaporator during the hot water storage operation and as a condenser during the normal operation by the operation of the four-way valve 5 and the like. The indoor heat exchanger 11
Indoor electric fan 11a and indoor exchanger sensor 11
s, which is installed indoors and functions as an evaporator.

A refrigerant sensor 15s is provided in the refrigerant pipe 15 which communicates the suction side 4b of the compressor 4 with the outdoor heat exchanger 9 and the indoor heat exchanger 11.

As shown in FIG. 2, the heat pump hot water supply air conditioner 1 is controlled by a control device 12 to determine whether or not a cooling operation command has been issued.
The operation can be performed in three modes of a normal cooling operation, a cooling hot water storage operation, and a hot water storage operation selected according to the remaining amount of hot water (hot water temperature) in the hot water storage tank 14.

Next, the operation mode of the heat pump hot water supply air conditioner 1 will be described.

For example, in the normal cooling operation mode, as shown in FIG. 3, the refrigerant in the refrigerating cycle 2 receives the refrigerant 4a of the compressor 4, the four-way valve 5, the outdoor heat exchanger as shown by the arrow in FIG. 9, a cycle of returning to the suction side 4b of the compressor 4 via the outdoor flow control valve 8, the indoor flow control valve 10, the indoor heat exchanger 11, and the four-way valve 5 is repeated. In this cooling operation, the refrigerant flowing through the refrigeration cycle 2 is compressed by the compressor 4, condensed and liquefied by the outdoor heat exchanger 9, and decompressed by the indoor flow control valve 10,
It evaporates in the indoor heat exchanger 11 to cool the room. During the normal cooling operation, the refrigerant does not flow into the water heating heat exchanger 6 due to the operation of the four-way valve 5, so that the hot water (water) in the hot water storage tank 14 is not newly heated.

In the cooling hot water storage operation mode, as shown in FIG. 4, the water temperature is lowered (for example, 45 ° C. or less) by new water supply, heating is required, and the refrigerant in the refrigeration cycle 2 is a part of the refrigerant. Is indicated by a solid arrow in FIG.
Through the discharge side 4a of the compressor 4, the four-way valve 5, the outdoor heat exchanger 9, the water heating heat exchanger 6, the two-way valve 7, the outdoor flow control valve 8, the outdoor heat exchanger 9, and the four-way valve 5. 4, and the remainder passes through the indoor flow control valve 10, the indoor heat exchanger 11, the refrigerant pipe 15, and the four-way valve 5 as shown by the dotted arrow in FIG. And returns directly to the suction side 4b of the compressor 4.

In this cooling hot water storage operation (the remaining hot water is small), the refrigerant flowing through the refrigeration cycle 2 is compressed by the compressor 4, condensed and liquefied by the water heating heat exchanger 6, and decompressed by the outdoor flow control valve 8. Then, it evaporates in the outdoor heat exchanger 9, is further reduced in pressure by the indoor flow control valve 10, evaporates in the indoor heat exchanger 11, and cools the room. In addition, hot water storage tank 1
Since the amount of remaining hot water in the bath 4 is small, the temperature of the hot water is reduced due to the supply of hot water, and heating is required.

In the cooling hot water storage operation (remaining hot water), the compressor 4 supplies sufficient hot water even when the required cooling frequency from the room input through the control device 12 is low (when the cooling load is small). The frequency (50H
z), the operation is forcibly increased, and when the required cooling frequency from the room is high (when the cooling load is large),
The operation is performed according to the required frequency.
The indoor side flow control valve 10 is a superheat of the indoor side heat exchanger 11 (the indoor side heat exchanger sensor 11s and the suction sensor 15
is controlled by the output from the control device 12 so that the temperature difference from the outside temperature is kept constant.
The opening degree varies according to the required cooling frequency from the room input via the control device 12.

Further, in the hot water storage operation mode, as shown in FIG. 2, there is no cooling command, but a new water supply is required. Further, as shown in FIG. 5 flows as indicated by the middle arrow, the discharge side 4a of the compressor 4, the four-way valve 5, the water heating heat exchanger 6, the two-way valve 7, the outdoor flow control valve 8, the outdoor heat exchanger 9, and the four-way valve 5. And returns to the suction side 4b of the compressor 4 via. In this hot water storage operation, the refrigerant flowing through the refrigeration cycle 2 is compressed by the compressor 4 and heats the hot water by the heat of condensation of the refrigerant in the water heating heat exchanger 6. In other words, the refrigeration cycle 2 heats (stores hot water) water by passing the refrigerant through the water heat exchanger 6 by switching the four-way valve 5, but does not cool the room. In this hot water storage operation, the actual operating frequency of the compressor 4 is 5
It is operated at 0 Hz.

As described above, the heat pump hot water supply air conditioner 1 is selected as shown in FIG. 2 by the control device 12 according to the presence or absence of a cooling operation command and the remaining amount of hot water (hot water temperature) in the hot water storage tank 14. The operation can be performed in three modes of a cooling operation, a cooling hot water storage operation, and a hot water storage operation.

Next, the operation of the heat pump hot water supply air conditioner 1 according to the present invention will be described.

The operation mode of the heat pump hot water supply air conditioner 1 is determined according to the procedure shown in FIG.

First, FIG. 1 shows. The control device 12 determines the indoor heat exchanger sensor 11s, the water temperature sensor 14
After reading the input signal from s, it is determined in step S2 whether there is a cooling command. And this judgment is Yes
If so, it is determined whether the temperature of the hot water in the hot water storage tank 14 detected by the water temperature sensor 14s in step S3 is higher or lower than 45 ° C. If this determination is Yes, the refrigeration cycle 2 enters the normal operation mode. If No, the operation enters the cooling hot water storage operation mode.

If No in step S2,
In step S4, similarly to step S3, it is determined whether the temperature of the hot water in the hot water storage tank 14 is higher or lower than 45 ° C. If this determination is Yes, refrigeration cycle 2
Is not operated and is kept stopped. If No, the operation mode is the hot water storage operation mode.

When the normal operation mode is selected in step S3, as shown in FIG. 3 and as described above, the refrigerant does not flow to the water heating heat exchanger 6, so that the room is cooled but the hot water is stored. Hot water (water) in the tank 14 is not newly heated.

When the cooling hot water storage operation mode is selected in step S3, as shown in FIG. 4 and as described above, the cooling hot water storage operation (remaining hot water small) requires indoor cooling and new water supply. In this cooling hot water storage operation (the remaining hot water is small), the refrigerant flowing through the refrigeration cycle 2 is condensed in the water heating heat exchanger 6 and heats the water in the hot water storage tank 14, and the outdoor heat exchanger 9 and It evaporates in the indoor heat exchanger 11 and cools the room by the indoor heat exchanger 11.

Further, in the cooling hot water storage operation (the remaining hot water is small), when the cooling operation required operation frequency is low (for example, 30).
7), the actual operating frequency of the compressor 4 is forcibly increased to 50 Hz by the control device 12 as shown in FIG. 7, and sufficient heat radiation from the water heating heat exchanger 6 is performed.
Large hot water storage capacity can be obtained. When the required cooling operation frequency is higher than 50 Hz, the actual operation frequency of the compressor 4 is the required cooling operation frequency.

The opening degree of the outdoor flow control valve 8 is 60% of the opening degree (300 pulses) with respect to the full opening (500 pulses), and the overall balance of the refrigeration cycle 2 is as follows. ((Temperature difference between indoor side heat exchanger sensor 11s and suction sensor 15s)) It is ensured by performing constant control, and heat pump hot water supply air conditioner 1 can be operated in a stable state. , The cooling capacity for cooling the room is controlled by adjusting the opening of the outdoor flow control valve 8 and controlling the flow rate of the refrigerant to the room side. Thus, the cooling capacity balanced with the load can be exhibited.

Further, as shown in FIG. 7, when the required cooling operation frequency is 50 Hz or more due to load fluctuation, the opening degree of the outdoor flow control valve 8 becomes 0 (fully closed). At this time, the hot water storage capacity further increases due to the increase in the operating frequency, and the refrigerant no longer flows to the outdoor flow control valve 8 as indicated by the solid arrow in FIG. Since the flow goes to 11, the cooling capacity is also increased, and a cooling capacity corresponding to the load is obtained.

In step S4, when the hot water storage operation mode is selected, as shown in FIG. 5 and as described above, the compressor 4 is operated at a constant frequency (50 Hz), and the refrigerant flowing through the refrigeration cycle 2 is the compressor 4 And heat is exchanged with water through the water-heating heat exchanger 6 to heat the water. However, the refrigerant does not flow through the indoor heat exchanger 11 and the room is not cooled. In this hot water storage operation, since the actual operation frequency of the compressor 4 is fixed to 50 Hz by the control device 12, sufficient heat radiation is performed from the water heating heat exchanger 6, and hot water storage capacity is obtained.

Heat pump hot water supply air conditioner 1 as described above
In the operation of (1), waste heat during refrigeration cycle operation is used for storing hot water (water heating), so that energy saving can be achieved. Further, cooling capacity can be increased in accordance with indoor load while hot water storage capacity is secured. Because it can be changed, it is also excellent in comfort. Further, the operation of the heat pump hot water supply air conditioner 1 is performed in three operation modes of a normal cooling operation, a cooling hot water storage operation, and a hot water storage operation. Hot water storage and cooling can be performed.

[0037]

According to the heat pump hot water supply air conditioner according to the present invention, it is possible to provide a heat pump hot water supply air conditioner that can utilize the exhaust heat of the indoor cooling refrigeration cycle and can operate comfortably during the indoor cooling hot water storage operation. Can be.

That is, a compressor, a four-way valve, a water heating heat exchanger for heating water, a flow control valve for an outdoor heat exchanger, an outdoor heat exchanger, and a four-way valve are sequentially connected by a refrigerant pipe. Since the flow control valve for the heat exchanger and the indoor heat exchanger are heat pump hot water supply air conditioners provided in parallel with the flow control valve for the outdoor heat exchanger and the outdoor heat exchanger, the exhaust heat during the cooling operation is stored in the hot water. It is possible to achieve energy saving by utilizing the above, and since the cooling capacity can be changed according to the load in the room while the hot water storage capacity is secured, the comfort is also excellent.

The heat pump hot water supply air conditioner has three operation modes of a normal cooling operation, a cooling hot water storage operation, and a hot water storage operation which are switched by a control device. Since the selection is made according to the water temperature, the hot water can be efficiently stored and cooled.

When the number of revolutions of the compressor is changed in accordance with the operation command frequency from the inverter and the required cooling frequency is low, the frequency of the compressor is fixed at a predetermined frequency, and the required cooling frequency is high. If
Since it is varied according to the required cooling frequency from the room, the actual operating frequency of the compressor is forcibly increased to a predetermined frequency, sufficient heat radiation from the water heating heat exchanger is performed, and hot water storage capacity is obtained. Further, even when the required cooling operation frequency is high, the indoor cooling capacity is also increased, and the capacity corresponding to the load can be obtained.

In the cooling hot water storage operation mode, the flow rate control valve for the indoor heat exchanger is controlled so that the superheat of the indoor heat exchanger becomes constant, and the opening degree is controlled in accordance with the required cooling frequency from the room. Therefore, the balance of the entire refrigeration cycle is secured, the heat pump hot water supply air conditioner can be operated in a stable state, and the hot water can be reliably stored.
Room comfort is obtained.

[Brief description of the drawings]

FIG. 1 is a refrigeration cycle diagram used for a heat pump hot water supply air conditioner according to the present invention.

FIG. 2 is an explanatory diagram showing an operation mode of the heat pump hot water supply air conditioner according to the present invention.

FIG. 3 is a refrigeration cycle diagram showing a normal operation state of the heat pump hot water supply air conditioner according to the present invention.

FIG. 4 is a refrigeration cycle diagram showing a cooling hot water storage operation state of the heat pump hot water supply air conditioner according to the present invention.

FIG. 5 is a refrigeration cycle diagram showing a hot water storage operation state of the heat pump hot water supply air conditioner according to the present invention.

FIG. 6 is a flowchart showing a procedure of a subroutine for determining an operation mode of the heat pump hot water supply air conditioner according to the present invention.

FIG. 7 is a comparison table showing operating conditions in a cooling hot water storage operation of the heat pump hot water supply air conditioner according to the present invention.

FIG. 8 is a refrigeration cycle diagram of a conventional heat pump hot water supply air conditioner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat pump hot-water supply air conditioner 2 Refrigeration cycle 3 Inverter 4 Compressor 5 Four-way valve 6 Water heat exchanger 7 Two-way valve 8 Flow control valve for outdoor heat exchanger 9 Outdoor heat exchanger 9a Outdoor electric fan 9s Outdoor heat exchange Heat sensor 10 Indoor-side heat exchanger flow control valve 11 Indoor-side heat exchanger 11a Indoor-side electric fan 11s Indoor-side heat exchanger sensor 12 Control device 13 Hot water supply device 14 Hot water storage tank 14s Water temperature sensor 15 Refrigerant pipe 15s Suction sensor

Claims (4)

[Claims] 1. A compressor, a four-way valve, a water heating heat exchanger for heating water, a flow rate control valve for an outdoor heat exchanger, an outdoor heat exchanger, and the four-way valve are sequentially connected by a refrigerant pipe, and A heat pump hot water supply air conditioner, wherein a flow control valve for an inner heat exchanger and an indoor heat exchanger are provided in parallel with the flow control valve for an outdoor heat exchanger and the outdoor heat exchanger. 2. The heat pump hot water supply air conditioner has three operation modes, a normal cooling operation, a cooling hot water storage operation, and a hot water storage operation, which are switched by a control device. The heat pump hot water supply air conditioner according to claim 1, wherein the heat pump hot water supply air conditioner is selected according to a water temperature of the heat pump. 3. When the rotation speed of the compressor is changed according to the operation command frequency from the inverter and the required cooling frequency is low, the compressor frequency is fixed to a predetermined frequency, and the required cooling frequency is reduced. If high,
3. The heat pump hot water supply air conditioner according to claim 1, wherein the heat pump hot water supply air conditioner is varied according to a required cooling frequency from a room. 4. In the cooling hot water storage operation mode, the indoor heat exchanger flow control valve is controlled so that the superheat of the indoor heat exchanger becomes constant, and the opening degree is adjusted in accordance with the required cooling frequency from the room. 3. The control according to claim 2, wherein
Or the heat pump hot water supply air conditioner according to 3.