JPH01285758A - Heat pump type room cooling and hot-water supplying machine - Google Patents

Abstract

PURPOSE:To improve an operating efficiency of the present device by a method wherein the simultaneous room cooling and hot-water supplying operations are controlled automatically within a range capable of maintaining a high energy efficiency in a relation between a hot-water temperature in a hot-water reserving tank and an atmospheric temperature. CONSTITUTION:The existence of the demand of supplying hot-water is discriminated when there is the demand of room cooling. When there is the demand of supplying hot-water also, an atmospheric temperature Tb detected by an atmospheric temperature sensor 35 and a detecting hot-water temperature Tw inputted from a hot-water supply controller 43 are read respectively and a temperature difference between the detecting hot-water temperature Tw and the atmospheric temperature Tb is compared with a preset reference value (e.g., 30 deg.C). When the temperature difference is lower than the reference value, the simultaneous operation control is effected and an operation under this operation mode may be started.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a heat pump type cooling water heater.

(Prior Art) As a conventional example of a heat pump type cooling water heater, there can be mentioned, for example, a device described in Japanese Patent Application Laid-Open No. 59-231354. In this device, an indoor unit having an indoor heat exchanger and a hot water supply unit having a heat exchanger for hot water supply arranged in a hot water storage tank are connected to an outdoor unit having a compressor and an outdoor heat exchanger. The cooling operation is performed by circulating the refrigerant discharged from the compressor from the outdoor heat exchanger to the indoor heat exchanger, and the cooling operation is performed by circulating the refrigerant discharged from the compressor from the outdoor heat exchanger to the outdoor heat exchanger. In addition to performing hot water heating operation to heat hot water,
Further, when there is a cooling operation request from the indoor unit and a hot water heating operation request from the hot water supply unit at the same time, the refrigerant discharged from the compressor is circulated from the hot water supply heat exchanger to the indoor heat exchanger. The system is designed to perform simultaneous cooling and hot water supply operation (hereinafter abbreviated as simultaneous operation).

In the refrigerant circulation cycle during simultaneous operation, the amount of heat exchanged on both the evaporation side and the condensation side is used for cooling and hot water heating, respectively. Therefore, the energy efficiency (hereinafter referred to as EER) during the above simultaneous operation is ) can be calculated as the sum of the heat exchange amounts on the evaporation side and condensation side divided by the input power to the compressor.On the other hand, the heat exchange amount in the outdoor heat exchanger is not utilized. Therefore, for example, in cooling operation, EEE is given by the ratio of the amount of heat exchange only on the evaporation side to the input power. As a result, in the above-mentioned simultaneous operation, an operation with a higher EER is usually performed compared to the cooling operation or the hot water heating operation.

(Problem to be solved by the invention) In recent years, by using a mixed refrigerant that has a variable condensing temperature range up to a higher temperature,
It has become possible to heat hot water in a hot water storage tank to a high temperature exceeding, for example, 60° C., and in such devices, the EER during the above-mentioned simultaneous operation may be lower than during cooling operation. This results in a refrigerant cycle with a large temperature difference between the evaporation temperature on the cooling side and the evaporation temperature on the cooling side. This requires a large amount of compression work in the compressor, resulting in an increase in input power and, therefore, a decrease in EER. On the other hand, in cooling operation when the outside temperature is low, the condensation temperature in the outdoor heat exchanger becomes low, so that the EER increases, contrary to the above. As a result, in relation to the hot water temperature and the outside air temperature, which influence each EER, there are cases where the EER during simultaneous operation is lower than during cooling operation. However, conventionally, when there is a demand for operation of both cooling and hot water heating at the same time, the above-mentioned simultaneous operation is performed uniformly, which has caused the problem that a sufficiently satisfactory operating efficiency cannot be obtained. there were.

The present invention has been made in view of the above, and an object thereof is to provide a heat pump type air-conditioning water heater that can improve operating efficiency compared to the conventional one.

(Means for Solving the Problems) Therefore, the heat pump type cooling water heater of the present invention includes an outdoor unit x having a compressor 1 and an outdoor heat exchanger IO, and an indoor unit A-D having an indoor heat exchanger 19. , a hot water supply heat exchanger 23 for heating hot water in the hot water storage tank 31
As shown in FIG. 1, this is a heat pump cooling water heater connected to a hot water supply unit Y having a hot water supply unit Y, which includes a hot water temperature detection means 34 for detecting the temperature of the hot water, and an outside temperature detection means for detecting the outside temperature. When there is a cooling operation request signal from the indoor units A to D and the temperature difference obtained by subtracting the detected outside air temperature from the detected hot water temperature is below the reference value, the refrigerant discharged from the compressor 1 is Simultaneous operation control means 41 is provided for controlling the hot water to be circulated from the hot water supply heat exchanger 23 to the indoor heat exchanger 19 to perform cooling and hot water heating at the same time.

(Function) In the heat pump type cooling water heater described above, simultaneous operation of cooling and hot water heating is performed when the temperature difference obtained by subtracting the detected outside air temperature from the detected hot water temperature in the hot water storage tank 31 is below the reference value. It is carried out on a limited basis.

In other words, by determining in advance the temperature difference between the hot water temperature and the outside air temperature that makes the EER of simultaneous cooling/hot water heating operation and cooling operation approximately equal, and setting it as the above reference value, the EER of simultaneous cooling/hot water heating operation can be improved. Automatically limited to a range that remains high. As a result, it becomes possible to select a more efficient operating state and control the operation, and it is possible to improve the operating efficiency compared to the conventional method.

(Example) Next, a specific example of the heat pump type cooling water heater of the present invention will be described in detail with reference to the drawings.

First, FIG. 2 shows a refrigerant circuit diagram of a heat pump system configured to apply the present invention.

In the figure, X is an outdoor unit, and this outdoor unit y
To X has four indoor units A to D and a hot water supply unit Y.
are connected.

The above-mentioned outdoor unit Pipe 8 and second gas pipe 9 are connected. The compressor 1 has an inverter 5 for changing its rotational speed, that is, controlling its compression capacity, and the discharge pipe 2
A first solenoid valve 6 is interposed in the suction pipe 3, and an accumulator 7 is interposed in the suction pipe 3. The first gas pipe 8 is connected to an outdoor heat exchanger 10, and the second gas pipe 9 is connected to a header 11, with a first gas shutoff valve 12 interposed therebetween. An outdoor fan 30 is attached to the outdoor heat exchanger 10, and a liquid pipe 13 is also connected to the liquid pipe 13. Electric expansion valve 15
, a liquid receiver 16, and a first liquid closing top valve 17 are provided. And between the tip of the liquid pipe 13 and the header 11,
Multiple (four in the case of the figure) branch refrigerant pipes 18...18
are connected in parallel to each other, and these branch refrigerant pipes 18 and
・Indoor heat exchangers 19...19 (only one is shown) and second dynamic expansion valves 20...20 are installed in each of the indoor units A-D. The indoor unit A includes an exchanger 19 and an indoor fan 21.

Furthermore, the discharge pipe 2 of the compressor 1 is provided with a hot water supply gas pipe 2.
A hot water supply liquid pipe 24 is connected to a liquid receiver 16 interposed in the liquid pipe 13, and a hot water supply unit Y is connected between the hot water supply gas pipe 22 and the hot water supply liquid pipe 24. A hot water supply heat exchanger 23 is connected. The hot water supply gas pipe 22 is equipped with a second magnetic valve 25 and a second gas shutoff valve 28, and the hot water supply liquid pipe 24 is equipped with a cavity valve 26, a check valve 27, and a second liquid shutoff valve 29. Each of them is interposed in turn.

The hot water supply heat exchanger 23 is disposed on the bottom side of a hot water storage tank 31 constituted by a cylindrical sealed tank, and is configured to heat the hot water in the hot water storage tank 31 by the condensation heat of the condensed refrigerant. There is. A hot water supply pipe 32 is connected to the hot water supply port on the upper end side of the hot water storage tank 31, and a water supply pipe 33 is connected to the water supply port on the bottom side. When the valve is opened, the hot water in the hot water storage tank 31 is pushed up from the upper side into the hot water supply pipe 32 by the pressure of the tap water acting through the water supply pipe 33, and the amount of hot water dispensed is The same amount of water is replenished to the bottom side of the hot water storage tank 31 through the water supply pipe 33. And hot water tank 31
A hot water temperature sensor (water temperature detection means) 34 constituted by, for example, a thermistor is installed at the bottom side of the outer peripheral wall surface of the
is attached to detect the temperature of hot water in the hot water storage tank 31.

Furthermore, at an appropriate location within the outdoor unit X, preferably on the outside air inflow path when the outdoor fan 30 is in operation,
An outside temperature sensor (outside temperature detection means) 35 for detecting outside air temperature is provided.

In the heat pump system with the above configuration, first we will explain the refrigerant circulation control during heating operation.
The first solenoid valve 6 is opened, the second solenoid valve 25 is closed, and the compressor 1
The refrigerant discharged from the refrigerant is condensed in each indoor heat exchanger 19 via the four-way switching valve 4 and the second gas pipe 9, then evaporated in the outdoor heat exchanger 10 via the liquid pipe 13, and then, In this case, the degree of superheating of the evaporative refrigerant is controlled by returning the flow from the first gas pipe 8 and the four-way switching valve 4 to the compressor 1.
The second step is performed by the dynamic expansion valve 15, and the second is performed by the dynamic expansion valve 20...20.
Then, the amount of refrigerant distributed to each indoor heat exchanger I9...19 is controlled.

On the other hand, cooling operation is performed by switching the four-way switching valve 4 from the above to circulate the refrigerant discharged from the compressor 1 from the outdoor heat exchanger IO to each indoor heat exchanger 19. At this time, number one! The dynamic expansion valve I5 is fully opened, and each second electric expansion valve 2
0...20 controls the degree of superheating of the refrigerant. Note that the second electric expansion valve 20 connected to the indoor unit A of the room where cooling is stopped is fully opened.

Next, in the hot water heating operation, the first solenoid valve 6 is closed, and the second solenoid valve 2 is closed.
5 is opened and the compressor 1 is operated. Then, the refrigerant passes through the hot water supply gas pipe 22, condenses in the hot water supply heat exchanger 23, then passes through the hot water supply liquid pipe 24 and the liquid pipe 13, and discharges in the outdoor heat exchanger lo. The flow is returned to the compressor 1 via the first gas pipe 8 and the four-way switching valve 4. In this case, each of the second electric expansion valves 20 . . . 20 is fully closed, and the first electric expansion valve 15 controls the degree of superheating of the evaporative refrigerant.

For simultaneous operation of heating and hot water heating, both the first and second solenoid valves 6.25 are opened, the refrigerant is condensed in both the indoor heat exchanger 19 and the hot water heat exchanger 23, and outdoor heat exchange is performed. vessel 10
This can be done by circulating a refrigerant that is evaporated at a temperature.

In addition, the first solenoid valve 6 controls the simultaneous operation of cooling and hot water heating, that is, the operation of heating the hot water in the hot water storage tank 31 with the cooling waste heat.
is closed, the second electromagnetic valve 25 is opened, and the first electric expansion valve 15 is fully closed. Then, the refrigerant passes through the hot water supply gas pipe 22 and condenses in the hot water heat exchanger 23, and the hot water supply Liquid pipe 24
, liquid receiver 16, liquid pipe 13, and each indoor heat exchanger 19...
19, and then the second gas pipe 9, the four-way switching valve 4
is returned to the compressor 1 via . In this case, the degree of superheating of the evaporative refrigerant is controlled in each of the second electric expansion valves 20...20.

Each of the above-mentioned operations has a control configuration in which the indoor temperature and the hot water temperature in the hot water storage tank 31 are respectively detected, and each detected temperature approaches the set temperature. Operation control when performing air conditioning inside will be explained in more detail.

FIG. 3 shows the operation control system of the heat pump system. As shown in the figure, the outdoor unit X includes an outdoor control device 41 that functions as a simultaneous operation control means for cooling and heating hot water, as will be described later. In addition, each of the indoor units A to D has an indoor control device 42 (only indoor unit A is shown) and a hot water supply unit.
Each of the units Y is equipped with a hot water supply control device 43. A remote controller 44 for operation and a room temperature sensor 45 for detecting the room temperature are connected to each of the indoor control devices 42, and the remote controller 44 for operation operates a drive switch and a temperature setting for setting the desired room temperature. It has a switch. On the premise that the operation switch is ON, when the temperature detected by each room temperature sensor 45 is higher than the set temperature, a cooling operation request signal (hereinafter abbreviated as cooling request) is sent.
is outputted from each indoor control device 42 to the outdoor control device 41, and at the same time, a temperature difference signal between the detected temperature and the set temperature is outputted.

On the other hand, the hot water supply control device 43 includes the hot water temperature sensor 34.
is connected thereto, and further connected to a remote control box 46 placed in a kitchen or the like.

This remote control box 46 is provided with a hot water supply heating operation switch and a hot water temperature setting switch.

When the hot water heating operation switch is ON and the hot water temperature detected by the hot water temperature sensor 34 is lower than the set hot water temperature,
A hot water supply heating operation request signal (hereinafter abbreviated as hot water supply request) and the detected hot water temperature are outputted from the hot water supply control device 43 to the outdoor control device 41. Note that hot water in the hot water storage tank 31 can be heated to a maximum of 65° C. in the hot water supply heating operation, and any hot water temperature within this temperature range can be set as the set hot water temperature.

The outdoor control device 41 to which each of the above-mentioned driving request signals is inputted performs a process according to a control flowchart for specifying a driving mode, which will be described later, based on the outside temperature detected by the outside temperature sensor 35 connected to the outdoor control device 41. identify any one of the following operating modes: cooling operation, simultaneous cooling and hot water heating operation (hereinafter abbreviated as simultaneous operation), and hot water heating operation, and first output a specific mode signal to the valve switching control device 47;
As a result, the operations of the first and second solenoid valves 6.25, the four-way switching valve 4, and the first and second electric expansion valves 15.20 are controlled to provide refrigerant circulation paths according to each of the operation modes. Ru. Further, the outdoor control device 41 generates a frequency signal for driving the compressor, and outputs this to the inverter control device 48. During cooling operation and simultaneous operation, it first outputs the initial setting frequency according to the total rated capacity of the indoor units requesting cooling and the maximum value of the temperature difference signal for each indoor unit, and then changes the operating mode. switching,
Alternatively, until the number of operating rooms increases or decreases, changes in the maximum value of the temperature difference signal are made, for example, by PID control, in accordance with changes in the air conditioning load on the indoor side. Further, during the hot water heating operation, the output at a predetermined frequency is continued. The compressor 1 is driven by the inverter control device 48 at a compression capacity corresponding to such a frequency signal.

Next, based on each operation request signal, the outdoor control device 41
The specific operation of the driving mode performed in will be explained with reference to the control flowchart of FIG.

In the figure, step S1 is a step for determining whether or not there is a cooling request as described above; if there is a cooling request,
Next, in step S2, it is determined whether there is a request for hot water supply.

If there is also a hot water supply request, then in steps S3 and 84, the outside temperature Tb detected by the outside temperature sensor 35 and the detected hot water temperature Tw inputted from the hot water supply control device 43 are read, respectively. , In step S5, the temperature difference obtained by subtracting Tb from Tw is compared with a preset reference value (for example, 30°C). If the temperature difference is less than or equal to the reference value, in step S6, the above-described simultaneous operation is controlled and operation in this operation mode is started. Thereafter, the processes from step S1 to step S6 are repeated to continue the simultaneous operation.

On the other hand, in step S5, if the temperature difference exceeds the reference value, or if the temperature of the hot water in the hot water storage tank 31 increases due to the continuation of the simultaneous operation, the temperature difference exceeds the reference value. , move from step S5 to 36 and start cooling operation or switch to cooling operation,
In other words, even though a hot water supply request is issued, the hot water supply is not heated and the cooling operation is performed solely. In other words, if the water temperature is high and the outside temperature is low (and the above temperature difference becomes large), as mentioned above, the energy efficiency during simultaneous operation will decrease, resulting in a reduction in cooling operation and hot water heating compared to simultaneous operation. Operating costs as a whole will be lower if these operations are performed independently of each other.In this way, the relationship between the hot water temperature and the outside temperature at which the operating efficiency is reversed is determined in advance and set as the above reference value. Therefore, depending on the determination result in step S5, a more efficient driving mode is automatically selected and the driving is performed.

In the flowchart of FIG. 4, when there is a cooling request and no hot water supply request, the cooling operation is performed by the process from steps S1 and S2 to step S7; In this case, the hot water supply heating operation is performed through the processes from step Sl to steps S8 and S9, and if there is no request for both cooling and hot water supply, the operation is stopped while continuing the repeated processes of steps S1 and S8.510. is maintained.

Although one embodiment of the present invention has been described above,
The above embodiments do not limit the present invention, and various changes can be made within the scope of the present invention. For example, in the above embodiment, a heat pump system having an air conditioning function for four rooms was explained as an example, but other devices having a function of cooling one room or multiple rooms other than four rooms and a hot water heating function may also be used. This invention can be applied.

(Effects of the Invention) As described above, in the heat pump type cooling water heater of the present invention, the simultaneous operation of cooling and hot water supply and heating is performed within a range where the EER is maintained high in relation to the hot water temperature in the hot water storage tank and the outside temperature. As a result of the automatic restriction, more efficient operation can be performed as appropriate, so it is possible to improve operational efficiency compared to the past.

[Brief explanation of the drawing]

Fig. 1 is a functional block diagram of the present invention, Fig. 2 is a refrigerant circuit diagram of a heat pump system constructed by applying the present invention, Fig. 3 is an operation control system diagram of the heat pump system, and Fig. 4 is a diagram of the heat pump system. 12 is a control flowchart for specifying the driving mode in FIG. 1...Compressor, 10...Outdoor heat exchanger, I9...
Indoor heat exchanger, 23... Heat exchanger for hot water supply, 31...
Hot water storage tank, 34... hot water temperature sensor (hot water temperature detection means),
35...Outside temperature sensor (outside temperature detection means), 41...
・Outdoor control device (simultaneous operation control means L A, B, C, D
...Indoor unit 1, X...Outdoor unit, Y...
・Hot water unit. Patent applicant: Daikin Industries, Ltd. Figure 1 Figure 3 Figure 4

Claims (1)

[Claims] 1. An outdoor unit (X) having a compressor (1) and an outdoor heat exchanger (10), indoor units (A) to (D) having an indoor heat exchanger (19), and a hot water storage tank (31). A heat pump cooling water heater connected to a hot water supply unit (Y) having a hot water heat exchanger (23) for heating hot water, the hot water temperature detection means (34) for detecting the temperature of the hot water. and an outside temperature detection means (
35), the compressor (1)
Simultaneous operation control means (41) is provided for controlling the refrigerant discharged from the hot water supply heat exchanger (23) to the indoor heat exchanger (19) to perform cooling and hot water heating operations simultaneously. A heat pump type air conditioner and water heater that is characterized by: