JPH0676864B2 - Heat pump type water heater - Google Patents

Description

Description: TECHNICAL FIELD 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, for example, the device described in JP-A-59-231354 can be cited. The device is equipped with one outdoor heat exchanger, one indoor heat exchanger, and one hot water supply heat exchanger arranged in the hot water storage tank, and the refrigerant discharged from the compressor is transferred from the outdoor heat exchanger to the indoor heat exchanger. The cooling operation is performed by circulating the water to the exchanger, and the hot water heating operation for heating the hot water in the hot water storage tank is performed by circulating the hot water supply heat exchanger to the outdoor heat exchanger. The discharge refrigerant is circulated from the hot water supply heat exchanger to the indoor heat exchanger to perform the cooling / hot water simultaneous operation in which the cooling waste heat is utilized for heating the hot water. When performing this cooling and hot water supply simultaneous operation, the preset hot water temperature that is fixed in advance is given as the target heating temperature on the hot water supply heating side so that the cooling capacity will not drop, and this set hot water temperature can be operated simultaneously. It is designed to control driving as. In other words, when the temperature of the hot water in the hot water supply tank rises, the heat exchange capacity of the hot water supply heat exchanger with this hot water decreases, and as a result, the cooling capacity of the indoor heat exchanger side decreases. Therefore, the maximum hot water temperature capable of maintaining the cooling capacity within a predetermined range is obtained in advance, and this is set as the set hot water temperature during the simultaneous cooling and hot water supply operation.

(Problems to be solved by the invention) By the way, in recent years, commercialization is progressing as a heat pump system that is capable of air conditioning operation and hot water supply heating operation over multiple rooms by providing a plurality of indoor heat exchangers, When simultaneously performing the above-described cooling and hot water supply heating in such an apparatus, the total heat exchange amount for maintaining a predetermined cooling capacity on the indoor side greatly depends on the number of indoor heat exchangers to be cooled. Therefore, even if the set hot water temperature that is uniquely fixed as described above is given to the hot water supply heating side as described above, the balance state between the two is not sufficiently ensured, and as a result, the heat inside the room is reduced. When the set hot water temperature is high relative to the exchange amount, the cooling capacity is reduced as described above and cooling comfort is impaired, and in the opposite case, the simultaneous operating range is narrowed and the cooling exhaust heat recovery efficiency is reduced. The question is that Will cause a problem.

The present invention has been made in view of the above, and an object thereof is to provide a heat pump type cooling and hot water supply device capable of maintaining cooling comfort and improving recovery efficiency of cooling exhaust heat.

(Means for Solving the Problem) Therefore, the heat pump type cooling and hot water supply apparatus of the present invention has a plurality of indoor units A each having an indoor heat exchanger 19 in an outdoor unit X having a compressor 1 and an outdoor heat exchanger 10. ~ D
Is connected to a hot water supply unit Y having a hot water supply heat exchanger 23 for heating hot water in the hot water storage tank 31, and a cooling operation request signal from the indoor units A to D and the hot water storage tank 31. When there is a hot water supply operation request signal issued by the hot water supply unit Y at the same time when the hot water temperature has not reached the set hot water temperature, the refrigerant discharged from the compressor 1 is transferred from the hot water supply heat exchanger 23 to the indoor heat exchange. A heat pump type cooling and hot water supply device comprising an operation control means 41 for controlling the simultaneous operation of cooling and hot water supply by circulating the water to the device 19, and the cooling operation request signal as shown in FIG. Load capacity grasping means 46 for grasping the total load capacity in the indoor units A to D, set temperature storing means 56 for storing a set temperature corresponding to the magnitude of the load capacity, and the load capacity grasping means.
Hot water temperature setting means for setting the preset temperature corresponding to the total load capacity grasped at 46 as the preset hot water temperature in the hot water supply unit Y
55 and.

(Function) In the above heat pump type cooling and hot water supply apparatus, the total load capacity on the indoor side according to the number of units performing the cooling operation and the like is grasped and grasped from the cooling operation request signal issued by the indoor units A to D. A set temperature corresponding to the total load capacity is appropriately selected from the set temperature storage means 56 and set as the set hot water temperature for hot water heating. Therefore, the indoor cooling capacity is reduced by previously obtaining the maximum hot water temperature that does not impair the cooling capacity for various total load capacities of the indoor units A to D that perform the cooling operation and storing it as the set temperature. Without doing so, it is possible to always perform simultaneous cooling and hot water supply operation while maintaining a higher hot water temperature range, thereby maintaining and improving cooling comfort and at the same time.
It is possible to improve the cooling exhaust heat recovery efficiency.

(Embodiment) Next, a specific embodiment of the heat pump type cooling and 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 by applying the present invention. In the figure,
X is an outdoor unit, and four indoor units A to D and a hot water supply unit Y are connected to the outdoor unit X.

The outdoor unit X has a compressor 1, and a discharge pipe 2 and a suction pipe 3 of the compressor 1 are connected to a four-way switching valve 4, and the four-way switching valve 4 further includes a first gas. The pipe 8 and the second gas pipe 9 are connected. The compressor 1 has an inverter 5 for controlling its rotation speed, that is, its compression capacity.
A first solenoid valve 6 is provided in the suction pipe 3, and an accumulator 7 is provided in the suction pipe 3. The first gas pipe 8 is connected to an outdoor heat exchanger 10, the second gas pipe 9 is connected to a header 11, and a first gas shutoff valve 12 is provided midway. The outdoor heat exchanger 10 has an outdoor fan 30.
And a liquid pipe 13 is further connected to the liquid pipe 13. The dryer pipe 14, the first electric expansion valve 15, the liquid receiver 16, and the first liquid are sequentially connected to the liquid pipe 13 from the outdoor heat exchanger 10 side. A shutoff valve 17 is provided. A plurality of (four in the case of the figure) branch refrigerant pipes 18 ... 18 are connected in parallel with each other between the tip of the liquid pipe 13 and the header 11, and these branch refrigerant pipes 18. Indoor heat exchanger 19 ... 19
(Only one unit is shown) and the second electric expansion valves 20 ... 20 are interposed. Although each of the indoor units A to D is shown only for one indoor unit A, it is composed of the indoor heat exchanger 19 and the indoor fan 21, respectively.

Further, the discharge pipe 2 of the compressor 1 has a hot water supply gas pipe 22.
However, the hot water supply liquid pipes 24 are respectively connected to the liquid receivers 16 provided in the liquid pipes 13, and between the hot water supply gas pipes 22 and the hot water supply liquid pipes 24, A hot water supply heat exchanger 23 is connected. In addition, in the hot water supply gas pipe 22,
The second solenoid valve 25, the second gas closing valve 28, and the hot water supply pipe 24
Capillary tube 26, check valve 27, second liquid shutoff valve 29
Are sequentially installed.

The hot water supply heat exchanger 23 is arranged on the bottom side of the hot water storage tank 31 constituted by a cylindrical closed 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 of the hot water storage tank 31. When the valve is opened, the hot water in the hot water storage tank 31 is pushed up from above by the pressure of tap water acting through the water supply pipe 33.
Hot water is discharged to 32, and the same amount of water as the hot water is supplied to the bottom side of the hot water storage tank 31 through the water supply pipe 33. A hot water temperature sensor 34 formed of, for example, a thermistor or the like is attached to a position on the bottom side of the outer peripheral wall surface of the hot water storage tank 31 to output the temperature of the hot water in the hot water storage tank 31.

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

On the other hand, the cooling operation is performed by switching the four-way switching valve 4 from the above to cause the refrigerant discharged from the compressor 1 to flow from the outdoor heat exchanger 10 to the indoor heat exchangers 19. At this time, the first electric expansion valve 15 is fully opened, and the second electric expansion valves 20 ... 20
Controls the degree of superheat of the refrigerant.

Next, in the hot water heating operation, the first solenoid valve 6 is closed and the second solenoid valve 25
Is opened to operate the compressor 1. Then, the refrigerant condenses in the hot water supply heat exchanger 23 via the hot water supply gas pipe 22, then evaporates in the outdoor heat exchanger 10 via the hot water supply liquid pipe 24 and the liquid pipe 13, and thereafter, The flow returns to the compressor 1 via the first gas pipe 8 and the four-way switching valve 4. In this case, the second electric expansion valves 20 ... 20 are fully closed, and the first electric expansion valve 15 controls the degree of superheat of the evaporated refrigerant. In the simultaneous operation of heating and hot water supply, both the first and second solenoid valves 6 and 25 are opened, the refrigerant is condensed in both the indoor heat exchanger 19 and the hot water supply heat exchanger 23, and the outdoor heat exchange is performed. This can be done by circulating the refrigerant that is evaporated in the vessel 10.

In addition, the first solenoid valve 6 is closed, the second solenoid valve 25 is opened, and the first electric expansion valve 15 is operated in the simultaneous operation of cooling and hot water supply heating, that is, an operation of heating the hot water in the hot water storage tank 31 by the cooling waste heat. Make it fully closed. Then, the refrigerant is condensed in the hot water supply heat exchanger 23 via the hot water supply gas pipe 22, and the hot water supply liquid pipe 24, the liquid receiver 16,
After being evaporated in each indoor heat exchanger 19 ... via the liquid pipe 13, it is then returned to the compressor 1 via the second gas pipe 9 and the four-way switching valve 4. In this case, the degree of superheat of the evaporated refrigerant is controlled in each of the second electric expansion valves 20.

Each of the above operations has a control configuration such that the detected temperature approaches the set temperature while detecting the indoor temperature and the hot water temperature in the hot water storage tank 31, respectively. The control of the hot water supply heating operation when performing cooling inside will be described in more detail.

FIG. 3 shows an operation control system of the heat pump system. As shown in the figure, the outdoor unit X is provided with an outdoor control device (operation control means) 41, each indoor unit A to D is provided with an indoor control device 42 (only the actual unit A is shown), and the hot water supply unit Y is provided. Hot water supply controller 43
The indoor control device 42 is connected to a driving remote controller 44 and a room temperature sensor 45 for detecting the room temperature. The operation remote controller 44 has an operation switch and a temperature setting switch for setting a desired room temperature, and on the assumption that the operation switch is ON, the temperature detected by each room temperature sensor 45 is When the temperature is higher than the set temperature (when the indoor thermostat is ON), the cooling operation request signal (hereinafter abbreviated as cooling request) is sent to each indoor control device.
42 is output to the outdoor control device 41, and at the same time, a temperature difference signal between the detected temperature and the set temperature is output.

The outdoor control device 41 is provided with a load capacity grasping section (load capacity grasping means) 46, a frequency control section 47 and a valve control section 48, and the cooling request is made by the load capacity grasping section 46 and the valve control section. Entered as 48. First, the valve control unit 48, the cooling request, according to the generation state of the hot water supply heating operation request signal further described below, the cooling operation, also hot water heating operation,
Either cooling or hot water heating simultaneous operation is specified, and the operation of each valve is controlled to provide each refrigerant circulation path. The second electric expansion valve 20 communicating with the indoor unit A, which does not require the cooling, is fully closed.

Next, the drive control of the compressor 1 by the frequency control unit 47 in the case where the cooling request is made and therefore the cooling operation is performed will be described. For this reason, the load capacity grasping unit 46 causes the room in which the cooling request is issued. Each load level of the unit A ... Is read from the load level storage unit 49, and the total load capacity .SIGMA.S obtained by summing these is calculated. The load level storage unit 49 stores "1" when the indoor unit has a rated capacity of 2240 kcal / h, "1.25" when the indoor unit has a rated capacity of 2800 kcal / h, and 3550 kcal / h.
The load levels set as "1.5" in the above, "2" in 4500 kcal / h, etc. are stored in advance for the respective indoor units A to D.

Further, the load capacity grasping unit 46 is generated at the time of start-up and when the total load capacity ΣS is changed, that is, the ON / OFF operation of the cooling operation switch in each room and the switching of the thermo ON / OFF accompanying the cooling operation. When the number of operating rooms increases or decreases, a load capacity change signal is generated, and when this signal is generated, the frequency control unit 47 reads the total load capacity ΣS. The temperature control unit 47 also receives the temperature difference signal ΔT from the indoor unit A, ... Which has a cooling request, and stores the initial setting frequency for the combination of the maximum value and the total load capacity ΣS as the initial frequency. It is read from the unit 50 and is output to the inverter post-natal device 51. The initial frequency storage unit 50 stores in advance a proper initial set frequency as a data table for each combination of various load capacities and temperature differences. The inverter controller 51 drives the compressor 1 at the initial setting frequency, and thereafter, after the rotational speed reaches the initial setting frequency, based on the subsequent change in the temperature difference signal ΔT. , The frequency control unit
At 47, for example, a frequency corresponding to a change in load is sequentially generated by PID control. In this way, by performing fine control of the compression capacity that can immediately respond to a large load change such as an increase or decrease in the number of operating rooms on the indoor side, a comfortable air conditioning operation can be performed.

It is premised that the cooling operation for the above-mentioned cooling request is performed prior to the hot water heating operation, but in the above, it is automatically switched to the simultaneous operation of cooling and hot water heating within the range where the cooling capacity is not impaired. The control configuration for this purpose will be described below.

The hot water temperature control device 43 of the hot water supply unit Y includes the hot water temperature sensor.
34 is connected, and further inside, a hot water temperature setting unit (hot water temperature setting means) 55 and a set temperature storage unit (set temperature storage means)
56 is provided, and the total load capacity ΣS and the load capacity change signal are input to the hot water temperature setting section 55 from the load capacity grasping section 46 of the outdoor control device 41.
Corresponding to various load capacity values in the set temperature storage unit 56, the upper limit hot water temperature that does not impair the cooling capacity during the cooling / hot water heating simultaneous operation described later is stored in advance, and in the hot water temperature setting unit 55. The set hot water temperature t is set according to the total load capacity ΣS according to the flowchart shown in FIG. That is, when the generation of the load capacitance change signal is determined in step S1, the total load capacitance ΣS is read in step S2, and then, for example, ΣS is determined according to the result of the magnitude determination step from step S3 to S7. When the value is 1 or less (including ΣS being 0, that is, the case where there is no cooling request), the process proceeds from step S3 to S8, and the set temperature storage unit 56 reads A (for example, the maximum temperature 65 that can be heated in the hot water heating operation). (° C.) is read and this is used as the set hot water temperature t. If ΣS exceeds 5, step
In S13, F (for example, 40 ° C.) lower than A is determined as the set hot water temperature t. Further, when ΣS is between 1 and 5, B, C, D, and E, which are set to have successively lower temperatures between A and F, are set to the set hot water temperature t. There is. And, assuming that the hot water supply heating operation switch (not shown) is ON, the hot water temperature sensor
When the detected hot water temperature at 34 is lower than the preset hot water temperature t, a hot water supply heating operation request signal (hereinafter abbreviated as hot water supply request) is generated by the hot water supply control device 43, and this is issued by the outdoor control device 41.
Is output to.

As a result of the above control, simultaneous cooling / hot water heating operation is performed in a temperature range in which the set hot water temperature is lowered as the total load capacity ΣS increases. For example, when there is a cooling request from all the rooms on the indoor side, and therefore ΣS exceeds 5, while the hot water temperature in the hot water storage tank 31 is lower than 40 ° C, simultaneous operation of cooling and hot water supply is performed, and Hot water supply heating operation that utilizes the cooling exhaust heat is performed. Then, when the temperature reaches 40 ° C., the hot water supply request is no longer generated, the cooling only operation is switched to, and the hot water supply heating is stopped. That is, as the hot water temperature rises, the heat exchange efficiency in the hot water supply heat exchanger 23 decreases, the condensing temperature rises, and the indoor heat exchanger
At 19 the evaporation temperature and the blowout temperature rise, and the cooling capacity is reduced. Therefore, the maximum hot water temperature at which the cooling capacity can be maintained within a predetermined range is obtained in advance, and this temperature range is controlled as the simultaneously operable range. In addition, when the number of operating indoors decreases and the total load capacity ΣS decreases, the total amount of heat exchange within the range where the predetermined indoor cooling capacity is maintained also decreases.
The range of simultaneous operation can be performed up to a temperature higher than 40 ° C without impairing the cooling capacity. Therefore, for example, in the above case, when the cooling alone operation is continued, there is a room in which the thermostat is turned off and the operation is stopped, and the number of operating units decreases and the total load capacity ΣS becomes 2.5, for example.
The set hot water temperature t is changed to the value of C (for example, 52.5 ° C),
As a result, a hot water supply request is again generated for the hot water temperature condition of 40 ° C. in the hot water heating operation described above, which causes
Simultaneous operation of cooling and hot water heating up to 2.5 ℃ is started.

As described above, the set hot water for hot water supply heating is changed to the maximum heating temperature that does not impair the cooling capacity according to the total load capacity on the indoor side performing the cooling operation, thereby maintaining and improving the cooling comfort. At the same time, the operation in which the simultaneous cooling / hot water supply operation range is maintained wider is performed, so that the operation with improved cooling exhaust heat recovery efficiency is performed. In the hot water supply independent operation without a cooling request, the above-mentioned value of, for example, 65 ° C. is set as the set hot water temperature, and the hot water supply request is input to the frequency control unit 47 together with the valve control unit 48. The specific frequency is output from the frequency control unit 47 to perform the operation.

As described above, one embodiment of the present invention has been described.
The above embodiment is not intended to limit the present invention, and various modifications can be made within the scope of the present invention. For example, the total load capacity grasped by the load capacity grasping section 46 in the above embodiment is a rating of each indoor unit. If the capacities are almost the same, it is possible to configure them as the number of operating machines. It is also possible to configure the load capacity grasping section 46 to grasp as an indoor unit whose operation switch is ON even in the thermo OFF state.

(Effects of the Invention) As described above, in the heat pump type cooling and hot water supply apparatus of the present invention, the set hot water for hot water supply heating is changed to a set hot water temperature according to a change in the number of indoor units performing the cooling operation. As a result, it is possible to operate with a wider range of simultaneous operation of cooling and hot water supply without deteriorating the cooling capacity on the indoor side, thereby maintaining and improving cooling comfort and improving cooling exhaust heat recovery efficiency. It becomes possible to do.

[Brief description of drawings]

1 is a functional block diagram of the present invention, FIG. 2 is a refrigerant circuit diagram of a heat pump system configured by applying the present invention, FIG. 3 is an operation control system diagram of the heat pump system, and FIG. 4 is the heat pump system. 3 is a control flowchart of a hot water temperature setting unit in FIG. 1 …… Compressor, 10 …… Outdoor heat exchanger, 19 …… Indoor heat exchanger, 23 …… Hot water heat exchanger, 31 …… Hot water storage tank, 41 ……
Outdoor control device (operation control means), 46 ... Load capacity grasping section (load capacity grasping means), 55 ... Hot water temperature setting section (hot water temperature setting means), 56 ... Set temperature storage section (set temperature storage means) .

Claims (1)

[Claims] 1. An indoor heat exchanger (1) is attached to an outdoor unit (X) having a compressor (1) and an outdoor heat exchanger (10), respectively.
A plurality of indoor units (A) to (D) having 9) and a hot water supply unit (Y) having a hot water supply heat exchanger (23) for heating hot water in the hot water storage tank (31) are connected. , A cooling operation request signal from the indoor units (A) to (D), and a hot water supply operation issued by the hot water supply unit (Y) when the hot water temperature in the hot water storage tank (31) has not reached the set hot water temperature. Simultaneous operation of cooling and hot water heating by circulating the discharge refrigerant from the compressor (1) from the hot water supply heat exchanger (23) to the indoor heat exchanger (19) when there is a request signal at the same time. A heat pump type cooling and hot water supply device comprising an operation control means (41) for controlling to perform a load for grasping a total load capacity of the indoor units (A) to (D) having the cooling operation request signal. Capacity grasping means (46) and setting according to the size of load capacity Temperature setting means (56) for storing the degree of temperature, and hot water temperature setting for setting the set temperature corresponding to the total load capacity grasped by the load capacity grasping means (46) as the set hot water temperature in the hot water supply unit (Y). Means (55)
And a heat pump type cooling and hot water supply device.