JPH0463306B2 - - Google Patents

Description

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

(Conventional technology) Conventional examples of heat pump heating and water heaters include:
For example, Japanese Utility Model Publication No. 60-17641 can be mentioned, and this device returns the refrigerant discharged from the compressor to the compressor through an indoor heat exchanger, an expansion valve, and an outdoor heat exchanger. At the same time, it has a structure in which a hot water supply heat exchanger is connected in parallel with the indoor heat exchanger. In this device, heating is performed by condensing high-pressure gas refrigerant from the compressor in an indoor heat exchanger, and high-pressure gas refrigerant from the compressor is condensed in a heat exchanger for hot water supply. It is designed to heat the water in the tank. In the above device, a pressure regulating valve is installed on the liquid refrigerant outlet side of the hot water supply heat exchanger, so that the amount of refrigerant distributed to both the indoor heat exchanger and the hot water supply heat exchanger can be adjusted. This is done for the following reasons. In other words, when the water temperature in the hot water storage tank is low, the refrigerant condensation temperature in the hot water heat exchanger decreases, and most of the refrigerant is distributed to the hot water heat exchanger. In this case, the blowout temperature decreases due to a decrease in the amount of refrigerant distributed, which causes discomfort to the user, but in order to prevent this,
The pressure regulating valve apparently increases the condensing pressure to ensure the amount of refrigerant distributed to the indoor heat exchanger.

(Problems to be Solved by the Invention) By the way, in the conventional heat pump type heating and water heaters described above, no consideration has been given to operation control.In other words, heating and hot water supply must be operated simultaneously under any conditions. Because it is done this way, it has the following drawbacks. Even if the refrigerant distribution amount is adjusted using the pressure regulating valve as described above, when the heating load is large, such as immediately after heating starts, there will still be a lack of heating capacity.
This means that it causes discomfort to the user. In addition, as mentioned above, by apparently increasing the condensing pressure of the hot water heat exchanger with the pressure regulating valve, there is a drawback that the efficiency of the heat pump decreases by that amount. There is also the disadvantage that the structure of the device becomes complicated due to the use of . On the other hand, if the water temperature is high and the condensed refrigerant temperature on the hot water heat exchanger side is higher than the condensed refrigerant temperature on the indoor heat exchanger side, the condensed temperature of the refrigerant will be lower than the indoor heat exchanger for heating. The decision was made by the device,
A non-condensable refrigerant that does not exchange heat passes through the heat exchanger for hot water supply, which not only makes it impossible to heat the hot water, but also disrupts the refrigeration cycle, resulting in a decrease in efficiency.

This invention was made to solve the above-mentioned conventional drawbacks, and its purpose is to make it possible to simultaneously operate heating and hot water supply with high efficiency while maintaining a comfortable heating condition. The objective is to provide a heat pump type heating and water heater.

(Means for Solving the Problems) Therefore, in the heat pump type heating and water heater of the present invention, the refrigerant discharged from the compressor 1 is passed through the indoor heat exchanger 19, the expansion mechanism 15, and the outdoor heat exchanger 10 in sequence. As shown in FIG. vessel 19
Heating load detection means 42 for detecting heating load on the side
and a hot water supply load detection means 30 for detecting the load on the hot water supply heat exchanger 23 side, and further includes a heating only operation when only a heating operation is requested, and a hot water supply only operation when only a hot water supply operation is requested. On the other hand, when there is both a request for heating operation and a request for hot water supply operation, the valve is activated to perform simultaneous operation of heating and hot water supply when the heating load is below the reference value and the hot water supply load is above the reference value. An operation control means 43 for controlling the switching means 33 is provided.

(Function) In the heat pump heating and water heater described above, heating and hot water supply are operated simultaneously only when the heating load is below a reference value and the hot water supply load is within the reference range. As a result,
It is possible to maintain the efficiency of the heat pump at a high level by avoiding simultaneous operation of heating and hot water supply when the water temperature is low or when the hot water temperature is high. Moreover, since simultaneous operation is performed only when the heating load is below the reference value, even if the heating side is affected by the hot water supply side, discomfort to the user can be prevented.

(Embodiments) Next, specific embodiments of the heat pump type heating 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, and as shown, this air conditioner has an outdoor unit X, indoor units A to D, and a hot water supply unit Y. The outdoor unit X has a compressor 1, and a discharge pipe 2 and a suction pipe 3 of the compressor 1 are each connected to a four-way switching valve 4. Note that the compressor 1 has an inverter 5 for controlling its rotational speed, that is, its compression capacity.
Further, a first electromagnetic valve 6 is provided in the discharge pipe 2, and an accumulator 7 is provided in the suction pipe 3. A first gas pipe 8 and a second gas pipe 9 are connected to the four-way switching valve 4, and the first gas pipe 8 is connected to an outdoor heat exchanger 10, and the second gas pipe 9 is also connected to an outdoor heat exchanger 10. is connected to header 11, and
A gas shutoff valve 12 is interposed in the middle. Further, a first liquid pipe 13 is connected to the outdoor heat exchanger 10, and this first liquid pipe 13 is connected to a liquid receiver 14, and a first expansion valve 15 is provided in the middle thereof.
is interposed. A second liquid pipe 16 is connected to the liquid receiver 14, and this second liquid pipe 16 has a liquid shutoff valve 17 interposed in the middle.
Between the second gas pipe 9 and the second liquid pipe 16, there are a plurality of (four in the case of the figure) branch refrigerant pipes 18...1.
8 are connected in parallel to each other, and each branch refrigerant pipe 18...18 is connected to an indoor heat exchanger 19...1, respectively.
9 (only one is shown) and second expansion valves 20...2
0 is interposed. Furthermore, each indoor unit A~
Although only the first indoor unit A is illustrated, D is constituted by the indoor heat exchangers 19...19 and the indoor fans 21...21.

On the other hand, a third gas pipe 22 is further connected to the discharge pipe 2 of the compressor 1, and a hot water supply heat exchanger 23 is connected to the third gas pipe 22. Further, the third liquid pipe 24
It is connected to the liquid receiver 14 at. A second solenoid valve 25 is interposed in the third gas pipe 22,
Further, a capillary reach tube 26 and a check valve 27 are interposed in the third liquid pipe 24 . Note 2
8 is a hot water storage tank.

In the refrigerant branch pipes 18...18, each indoor heat exchanger 19...19 and the second expansion valve 20
...20, the first temperature sensor 29...
The first temperature sensors 29...29 are connected to the indoor heat exchangers 19...29 during heating operation.
This is for detecting the temperature of the liquid refrigerant condensed in the refrigerant 19. Also, in the third liquid pipe 24, a second temperature sensor 30 is attached at a position between the hot water supply heat exchanger 23 and the check valve 27; This is for detecting the temperature of the liquid refrigerant condensed in the hot water supply heat exchanger 23 during operation. Note that the temperature of the third liquid pipe 24 detected by the second temperature sensor 30 is approximately the same as the temperature of the hot water in the storage tank 28.

During heating operation of the heating water heater, the compressor 1 is operated with the first solenoid valve 6 opened and the second solenoid valve 25 closed. Then, the refrigerant is transferred to the four-way switching valve 4,
Each indoor heat exchanger 19...
19, then evaporated in the outdoor heat exchanger 10 via the second liquid pipe 16 and the first liquid pipe 13,
Thereafter, the flow returns to the compressor 1 via the first gas pipe 8 and the four-way switching valve 4.

Also, during hot water supply operation, the first solenoid valve 6 is closed and the second solenoid valve 6 is closed.
The solenoid valve 25 is opened to operate the compressor 1.
Then, the refrigerant passes through the third gas pipe 22 and is condensed in the hot water supply heat exchanger 23, and then passes through the third liquid pipe 24, the liquid receiver 14, and the first liquid pipe 13 to the outdoor heat exchanger. After that, the gas is evaporated in the gas pipe 10, and then the flow is diverted to the compressor 1 via the first gas pipe 8 and the four-way switching valve 4 in the same manner as described above.

When heating and hot water supply are to be operated simultaneously, both the first solenoid valve 6 and the second solenoid valve 25 are opened, and the refrigerant discharged from the compressor 1 is transferred to the indoor heat exchanger 19 and the hot water supply. It is supplied to both the heat exchanger 23 and the heat exchanger 23 in parallel.

The cooling operation in the above device is performed by switching the four-way switching valve 4 and circulating the refrigerant from the outdoor heat exchanger 10 side to the indoor heat exchanger 19 side, and cooling/hot water supply operation is performed by switching the four-way switching valve 4. The refrigerant discharged from 1 is condensed in the hot water supply heat exchanger 23 via the third gas pipe 22, and then transferred to the third liquid pipe 2.
4, the liquid is evaporated in each indoor heat exchanger 19...19 via the liquid receiver 14 and the second liquid pipe 16, and then the second
This is done by circulating the gas in a circuit that returns to the compressor 1 via the gas pipe 9 and the four-way switching valve 4.

Next, regarding the operation control system of the heating and water heater mentioned above,
This will be explained based on FIG. First, outdoor unit
is an outdoor control device 31 and an inverter control device 3
1, but this inverter control device 3
Reference numeral 2 is for controlling the frequency of the inverter 5, that is, the rotation speed of the compressor 1. Furthermore, temperatures detected by the first temperature sensors 29 . . . 29 and the second temperature sensor 30 are input to the outdoor control device 31 . 33 is a valve switching means, and this valve switching means 33 is connected to the outdoor control device 31.
The operation of the first solenoid valve 6, the second solenoid valve 25, the four-way switching valve 4, etc. is controlled in response to commands from the controller, thereby controlling operating states such as heating operation, hot water supply operation, and simultaneous heating and hot water supply operation. It's something to save up. Furthermore, a remote control box 34 placed indoors such as a kitchen is connected to the outdoor control device 31.
By operating a hot water tank heating switch 35 provided in this box 34, a hot water tank heating request signal can be output to the outdoor control device 31. In this case, a hot water temperature thermometer 36 is arranged in the hot water storage tank 28, and when the hot water storage tank heating request signal is output and there is an operation request signal from the hot water temperature thermometer 36, hot water supply operation is performed. It's summery.

On the other hand, each of the indoor units A to D has an indoor control device 37;
has a heating switch 38, a cooling switch 39, a room temperature setting switch 40, and an indoor thermostat 41, and each indoor control device 37 sends a heating request signal, a cooling request signal, an indoor thermostat 41 to the outdoor control device 31. Air conditioning request or stop signal by thermometer 41, ΔT based on the temperature difference between indoor temperature and set temperature
The signals are outputted respectively. In the outdoor control device 31, a load grasping circuit 44 constituting a part of the heating load detection means 42 detects ΔT from the indoor units A to D during operation.
The total sum ΣΔT of the signals can be calculated.

Next, regarding the operation control method of the heating water heater mentioned above,
A state in which a heating operation is requested (a heating request signal is output from the heating switch 38, and the indoor thermostat 41
When there is a hot water supply operation request (a state in which a hot water storage tank heating request signal is output from the hot water tank heating switch 35 and an operation request signal is received from the hot water temperature thermostat 36), The operation control method will be mainly explained based on FIG. 4. First, in step S1, it is determined whether there is a request for heating or not. If YES, the next step S2 is followed, and if NO, it is determined whether there is a request for hot water supply, respectively. If step S2 is NO, heating-only operation is started in step S4, and this operation is continued until an air conditioning stop signal is output from the indoor thermostat 41 (step S5), and the process returns to step S1. If step S3 is NO, the process directly returns to step S1, while if YES, hot water supply operation is performed independently in step S6. This hot water supply operation is performed when there is a heating request signal (step S7) or when the hot water temperature thermometer 36 is turned off (step S7).
If the hot water supply operation continues until S8) and ends the hot water supply operation as described above (Step S9), the above step is continued.
Return to S1.

On the other hand, if step S2 is YES, that is, if there are both requests for heating operation and hot water supply operation, the next value of ~ is read out in step S10. That is, the temperature difference ΔT between the room temperature and the set temperature in the indoor units A to D during operation, the detected temperatures TL1...TL4 of the first temperature sensor 29 in the indoor units A to D during operation, and the second Detection temperature TCA of temperature sensor 30,
It is. Note that the temperature TCA detected by the second temperature sensor 30 is detected and stored for each hot water supply operation.
The previous TCA is read out when proceeding to step S10. Then, in subsequent steps S1 to S13, other judgments (1) to (3) are made based on the above values, and only when all of (1) to (3) are satisfied, heating is performed in step S14. - Simultaneous operation of hot water supply is performed, and in other cases, the process moves to step S4 and individual heating operation is performed.

(1) The sum of ΔT of indoor units A to D during heating operation, that is, the absolute value of ΣΔT, is smaller than a reference value (for example, 2° C.) (step S11).

This is to determine whether the heating load on indoor units A to D during heating operation is smaller than a reference value. In other words, if heating and hot water supply are operated simultaneously when the heating load is heavy, heating capacity may be insufficient and comfortable air conditioning may be impaired. Therefore, this is to be prevented.

(2) Indoor units A to D whose TCA is in heating operation
must be less than or equal to the maximum value TLn of TL1...TL4 (step S12).

This is because in a state where the condensed refrigerant temperature on the hot water supply heat exchanger 23 side is higher than the condensed refrigerant temperature on the indoor heat exchanger 19 side, the refrigerant condensation temperature will be higher on the heating indoor heat exchanger 19 side. This is because a non-condensable refrigerant that does not undergo heat exchange passes through the hot water supply heat exchanger 23, which not only prevents hot water from being heated but also disturbs the refrigeration cycle and reduces efficiency.

(3) TCA is within the standard temperature range (e.g. 20℃≦TCA
<52.5℃) (Step S13).

This is TCA, which means that if the temperature of the hot water to be heated is lower than 20℃, the hot water supply load becomes excessive and cold draft occurs.
In indoor units A to D, the air outlet temperature may drop, making it impossible to provide comfortable air conditioning.
To prevent this, heating and hot water supply are operated simultaneously when the TCA is higher than the reference temperature. The upper limit of TCA was set to ensure the heat resistance limit of equipment such as piping and the efficiency of the refrigeration cycle.

The simultaneous operation of heating and hot water supply in step S14 is continued until either the air conditioning stop signal from the indoor thermometer 41 (step S15) or the stop signal from the hot water temperature thermometer 36 (step S16) is output.

As mentioned above, in the above heating and water heater, the air conditioning load (absolute value of ΣΔT) on the indoor units A to D side is
is smaller than the standard value, and the load on the hot water supply side, that is, the temperature TCA of the hot water to be heated, is lower than the indoor heat exchanger 1.
When the temperature of the condensate refrigerant on the 5th side is below TLn and above the reference temperature (20℃), heating and hot water supply are operated simultaneously, so the simultaneous operation described above can be used to maintain a comfortable heating condition. However, it is possible to perform the process with high efficiency.

In addition, in the above, heating load detection means 42
A method of determining the air conditioning load by determining the temperature difference ΔT between the room temperature detected by the indoor thermostat 41 and the set temperature in the indoor units A to D during operation, and determining the sum ΣΔT of this in the load determining circuit 44. However, other methods may be adopted.
Further, in the above, the second temperature sensor 30 is used as the hot water supply load detection means, and the third temperature sensor 30 is used as the hot water supply load.
Although an example has been shown in which the temperature of the liquid pipe 24 is detected, other methods such as directly detecting the hot water temperature are also possible.In addition, in the above, the operation control means 43
Although it is composed of steps S11 to S14 and step S4 in FIG. 4, these structures can be arbitrarily modified within the range of achieving the same function.

(Effects of the Invention) In the heat pump type heating and water heater of the present invention, when the indoor heating load is below the standard value and the hot water supply load is within the standard range, heating and hot water supply are operated simultaneously. Therefore, it is possible to carry out the above-mentioned simultaneous operation with high efficiency while maintaining a comfortable heating state.

[Brief explanation of the drawing]

The figures show an embodiment of the heat pump type heating and water heater of the present invention. Fig. 1 is a functional system diagram, Fig. 2 is a refrigerant circuit diagram, Fig. 3 is a block diagram of an operation control system, and Fig. 4 is an operation control system. FIG. 3 is a flowchart diagram for explaining a control method. 1...Compressor, 10...Outdoor heat exchanger, 15...
...First expansion valve, 19...Indoor heat exchanger, 23...
Heat exchanger for hot water supply, 30... second temperature sensor (hot water supply load detection means), 33... valve switching means, 41...
...Indoor thermostat, 42...Heating load detection means, 43
...Operation control means.

Claims (1)

[Claims] 1. The refrigerant discharged from the compressor 1 is returned to the compressor 1 via the indoor heat exchanger 19, the expansion mechanism 15, and the outdoor heat exchanger 10 in order, and hot water is supplied in parallel to the indoor heat exchanger 19. In a heat pump type heating and water heater connected to a water supply heat exchanger 23, a heating load detection means 42 detects a heating load on the indoor heat exchanger 19 side, and a heating load detection means 42 detects a load on the hot water supply heat exchanger 23 side. and hot water supply load detection means 30,
Furthermore, when there is only a request for heating operation, the individual heating operation is performed, and when there is only a request for hot water supply operation, the individual operation for hot water supply is performed, while when there is both a request for heating operation and a request for hot water supply operation, the above heating load is less than the standard value. A heat pump type heating water heater characterized by having an operation control means 43 that controls a valve switching means 33 to perform simultaneous operation of heating and hot water supply when the hot water supply load is within a reference range.