Air conditioning and climate control systems

Abstract

An air conditioning system, according to a first aspect, comprises a heat source device including a refrigerant circuit circulating a refrigerant, an air conditioning unit configured to perform heating and cooling operations by heat exchange between the refrigerant and the indoor air, a hot water supply unit including a hot water storage tank configured to perform hot water supply operations by heating with the refrigerant, and a control unit configured to perform a first alternating operation of performing heating and hot water supply operations when a heating demand and a hot water supply demand are issued simultaneously, and to perform a second alternating operation of performing cooling and hot water supply operations.when a cooling request and a hot water supply request are issued simultaneously, the control unit being configured to perform control such that a first continuous operating time of the hot water supply operation in the first alternating operation differs from a second continuous operating time of the hot water supply operation in the second alternating operation.

Description

Technical area

[0001] The present disclosure relates to an air conditioning system and an air conditioning method. State of the art

[0002] In the related art, multi-purpose air conditioners are known that selectively perform an air conditioning operation of adjusting the indoor air temperature and a hot water supply operation of storing heat in a hot water storage tank by heating water in the hot water storage tank and heating the water. Some multi-purpose air conditioners cannot perform air conditioning operation during a period in which a hot water supply operation is performed. In such a multi-purpose air conditioner, the longer a period in which the hot water supply operation is performed, the longer a period in which hot water supply operation cannot be performed. When the hot water supply operation is performed for a long period, the indoor air temperature changes, which impairs comfort.

[0003] Even when a hot water demand for heated water is issued in response to a decrease in the amount of hot water in the hot water storage tank in the multi-purpose air conditioner, a technology is known to prevent indoor comfort from being impaired during the hot water demand. For example, an air conditioner disclosed in Patent Document 1 sets an upper limit time for continuing a hot water supply operation. This air conditioner stops the hot water supply operation and returns to the cooling operation if the water temperature in a hot water storage tank does not reach a target temperature even after exceeding the upper limit time. When the hot water supply operation is stopped, the air conditioner heats water in the hot water storage tank by supplying power to an auxiliary heater provided in a hot water storage tank. Citation listPatent document

[0004] Patent Document 1: PCT International Disclosure No. WO 2018 / 189942 Overview of the inventionThe problem to be solved by the invention

[0005] However, the air conditioner disclosed in Patent Document 1 starts a hot water supply operation using the auxiliary heater in response to returning to a cooling operation, and therefore, there is a problem that the amount of electricity consumed increases. In particular, since the auxiliary heater is an electric heater, a hot water supply operation using the auxiliary heater consumes more electricity than a hot water supply operation using an air conditioner and has lower operating efficiency, resulting in an increase in electricity consumption.

[0006] Even if the interruption time of an air conditioning operation is limited to an upper limit time by setting the upper limit time for a hot water supply operation as in Patent Document 1, the amount of change in indoor temperature may differ between cooling operation and heating operation. That is, if the air conditioning load is not the same between cooling operation and heating operation, the amount of change in indoor temperature between cooling operation and heating operation will differ even if the interruption time between cooling operation and heating operation is the same. Therefore, even if the upper limit time is set for a hot water supply operation as in the air conditioner of Patent Document 1, there is a concern that indoor comfort may be affected.

[0007] The present disclosure has been made to solve the problems described above, and an object thereof is to provide an air conditioner capable of suppressing an increase in power consumption and a decrease in indoor comfort even when the air conditioner performs a hot water supply operation using an auxiliary heater, and an air conditioning method. Means of solving the problem

[0008] An air conditioning system according to a first aspect comprises a heat source device having a refrigerant circuit in which a refrigerant circulates, an air conditioning unit configured to perform a heating operation and a cooling operation by heat exchange between the refrigerant and the indoor air, a hot water supply unit including a hot water storage tank and configured to perform a hot water supply operation by heating with the refrigerant, and a control unit configured to perform a first alternating operation in which the heating operation and the hot water supply operation are alternately performed when a heating request and a hot water supply request are issued simultaneously, and a second alternating operation in which the cooling operation and the hot water supply operation are alternately performed.when a cooling request and the hot water supply request are issued simultaneously, wherein the control unit is configured to perform control such that a first continuous operation time of the hot water supply operation in the first alternating operation is different from a second continuous operation time of the hot water supply operation in the second alternating operation.

[0009] An air conditioning method according to a second aspect is an air conditioning method in an air conditioning system including a heat source device including a refrigerant circuit in which a refrigerant circulates, an air conditioning unit configured to perform a heating operation and a cooling operation by heat exchange between the refrigerant and indoor air, and a hot water supply unit including a hot water storage tank and configured to perform a hot water supply operation by heating with the refrigerant, the air conditioning method comprising performing a first alternating operation in which the heating operation and the hot water supply operation are alternately performed when a heating request and a hot water supply request are issued simultaneously, and performing a second alternating operation,in which the cooling operation and the hot water supply operation are carried out alternately when a cooling request and the hot water supply request are issued simultaneously, wherein a first continuous operation time of the hot water supply operation in the first alternating operation is different from a second continuous operation time of the hot water supply operation in the second alternating operation. Effect of the invention

[0010] According to the present disclosure, it is possible to suppress an increase in power consumption and a decrease in indoor comfort even when an air conditioner performs a hot water supply operation using an auxiliary heater. Short description of the drawings Fig. 1 is a circuit diagram showing an example of a configuration of an air conditioner according to an embodiment. Fig. 2 is a block diagram showing an example of a functional configuration of the air conditioner according to the embodiment. Fig. 3 is a flowchart showing an example of a specific operation procedure performed by the air conditioner according to the embodiment. Fig. 4 is a diagram showing an operation of the air conditioner according to the embodiment, in which (a) is a diagram showing temporal changes in an operation mode of a heat source unit, (b) is a diagram showing temporal changes in water temperature in a hot water storage tank, and (c) is a diagram showing temporal changes in an operation of an electric heater. Fig. Figure 5 is a diagram showing an example of a relationship between an outside air temperature and a threshold T max (H) in the embodiment. Fig. 6 is a diagram showing an example of a relationship between an outside air temperature and a threshold T max (C) in the embodiment. Description of the embodiments

[0011] The embodiments of the present disclosure will be described below with reference to the drawings. The scope of the present disclosure is not limited to the following embodiment and can be arbitrarily modified within the scope of the technical idea of ​​the present disclosure. Furthermore, in the following drawings, the scale, number, and the like of each structure may differ from the scale, number, and the like of the actual structure to facilitate understanding of each configuration. (Configuration of an air conditioning system)

[0012] Fig. 1 is a circuit diagram showing an example of a configuration of an air conditioner according to an embodiment. The air conditioner includes, for example, a heat source unit 100, air conditioning units 200A and 200B, a hot water supply unit 300, an air conditioning controller 400, and a hot water supply controller 500. The air conditioner is, for example, a multi-purpose air conditioner that performs hot water supply operation, cooling operation, and heating operation by performing a vapor-compression refrigeration cycle operation. The air conditioner is installed in, for example, ordinary homes, but is not limited to this. Although the number of air conditioning units is two in the embodiment, the number is not limited to this and may be one, three, or more.A refrigerant in the air conditioning system can be, for example, a type of natural refrigerant such as R410A, R32, HFO-1234yf or hydrocarbons, but is not limited to these.

[0013] The heat source unit 100 functions as a heat source device in the air conditioner. The heat source unit 100 includes, for example, a compressor 102, a four-way valve 104, a heat source-side heat exchanger 106, a heat source-side blower 108, an accumulator 110, and a heat source control device 112. The heat source unit 100 includes, for example, a pressure sensor 120 and temperature sensors 122, 124, 126, and 128. The pressure sensor 120 and the temperature sensor 122 are provided in a refrigerant line on the outlet side of the compressor 102. The pressure sensor 120 detects a refrigerant pressure at the outlet side of the compressor 102. The temperature sensor 122, the temperature sensor 126, and the temperature sensor 124 are mounted on the liquid side of the heat source side heat exchanger 106 to measure the refrigerant temperature at an installation location.The refrigerant temperature sensor only needs to be capable of detecting a value equivalent to a refrigerant temperature, such as the temperature of a refrigerant line, or a value that can be converted to a refrigerant temperature. Temperature sensor 122 detects the temperature of the refrigerant line on the outlet side of compressor 102. Temperature sensor 124 detects the temperature of the refrigerant line near heat source-side heat exchanger 106. Temperature sensor 126 detects the temperature of the refrigerant line in heat source-side heat exchanger 106. The temperature detected by temperature sensor 126 is equivalent to a condensation temperature. Temperature sensor 128 detects the temperature of the air blown by heat source-side fan 108.

[0014] The heat source unit 100 is connected to the air conditioning unit 200A via the refrigerant lines 1a and 2a. The heat source unit 100 is connected to the air conditioning unit 200B via the refrigerant lines 1b and 2b. The heat source unit 100 is connected to the hot water supply unit 300 via the refrigerant lines 1c and 2c. A pressure reducing mechanism 130a is provided in the refrigerant line 2a. A pressure reducing mechanism 130b is provided in the refrigerant line 2b. A pressure reducing mechanism 130c is provided in the refrigerant line 2c.

[0015] Each of the air conditioning units 200A and 200B includes, for example, a heat exchanger 202, a blower 204, and an air conditioning control device 206. An air flow rate of the blower 204 can be adjusted. When the air conditioning units 200A and 200B are referred to collectively, they are simply referred to as "air conditioning units 200." Each of the air conditioning units 200A and 200B includes temperature sensors 210, 212, and 214. The temperature sensor 210 is provided on the gas side of the heat exchanger 202. The temperature sensor 212 is provided on the liquid side of the heat exchanger 202. The temperature sensors 210 and 212 detect a refrigerant temperature at an installation location. The temperature sensor 214 is provided at an air inlet of the blower 204. The temperature sensor 214 measures an air temperature in a room corresponding to the installation location of the air conditioning units 200A and 200B.

[0016] The hot water supply unit 300 includes, for example, a heat exchanger 302, a hot water storage tank 304, an electric heater 306, a hot water supply control device 308, and temperature sensors 310 and 312. The heat exchanger 302 exchanges heat between the water stored in the hot water storage tank 304 and a refrigerant. The hot water storage tank 304 stores the heat-exchanged water. The hot water storage tank 304 discharges hot water from the top of the tank in response to a hot water request issued by the hot water supply control device 308. Low-temperature water is supplied to the hot water storage tank 304 from a lower part of the tank in an amount equal to the amount of hot water discharged. The hot water storage tank 304 is, for example, a liquid-filled tank.The electric heater 306 is a heating unit that heats water in the hot water storage tank 304 by heating it in response to the supply of electrical energy. The electric heater 306 functions as an auxiliary heater that supports a hot water supply operation by the heat source unit 100. This allows the hot water supply unit 300 to perform a heating operation using the electric heater 306. The electric heater 306 functions as a second heat source in the air conditioner. The temperature sensor 310 is installed in the hot water storage tank 304 and measures the temperature of the water in the hot water storage tank 304. The temperature sensor 312 is installed on the liquid side of the hot water storage tank 304 and detects a refrigerant temperature at the installation site.

[0017] Fig. 2 is a block diagram showing an example of a functional configuration of the air conditioner according to the embodiment.

[0018] The heat source control device 112 is a computer implemented, for example, by a central processing unit (CPU) that executes a program. The heat source control device 112 controls the heat source unit 100 based on an air conditioning request issued by the air conditioning controller 400 or a hot water supply request issued by the hot water supply controller 500. The heat source control device 112 includes, for example, a measuring unit 112a, a communication unit 112b, a control unit 112c, and a storage unit 112d. The measuring unit 112a measures various temperatures and pressures by inputting signals detected by the temperature sensors 122, 124, 126, and 128 and the pressure sensor 120, and performs calculations based on the input signals.The communication unit 112b is connected to each part of the heat source unit 100 via communication lines and sends and receives various data and information. The communication unit 112b inputs an air conditioning request output from the air conditioning controller 400 (for example, a remote air conditioning controller) via the air conditioning control device 206 and delivers it to the control unit 112c. The air conditioning request is, for example, information indicating an operation mode of the air conditioner, such as a cooling request and a heating request. The air conditioning request may include information indicating a target temperature in the operation mode. The communication unit 112b inputs the hot water supply request output from the hot water supply controller 500 and delivers it to the control unit 112c.Alternatively, the hot water demand output from the hot water controller 500 (remote hot water supply controller) is transmitted via the hot water supply control device 308 and delivered to the control unit 112c. The control unit 112c controls the compressor 102, the four-way valve 104, the pressure reducing mechanisms 130a, 130b, and 130c, and the heat source-side blower 108 based on the measured temperatures and pressures, the air conditioning demand, and the hot water supply demand. The storage unit 112d includes a semiconductor memory and the like.The storage unit 112d stores, for example, a refrigerant temperature of each part in the air conditioner, a refrigerant pressure of each part in the air conditioner, air temperatures such as an indoor temperature and an outdoor air temperature, an operating state quantity such as a water temperature, set values ​​such as a target temperature, and various information in the heat source unit 100.

[0019] The air conditioning control device 206 is, for example, a computer implemented by a CPU that executes a program. The air conditioning control device 206 controls the air conditioning unit 200 based on an air conditioning request output from the air conditioning controller 400. The air conditioning control device 206 includes, for example, a measuring unit 206a, a control unit 206b, and a communication unit 206c. The measuring unit 206a measures various temperatures by inputting signals detected by the temperature sensors 210, 212, and 214 and performs calculations based on the input signals. The communication unit 206c is connected to each part of the air conditioning unit 200 via communication lines and sends and receives various data and information. The communication unit 206c receives an input of an air conditioning request output from the air conditioning controller 400.The control unit 206b controls the fan 204 based on the measured temperature and the air conditioning request.

[0020] The hot water supply control device 308 is, for example, a computer implemented by a CPU that executes a program. The hot water supply control device 308 controls the hot water supply unit 300 based on the hot water supply request issued by the hot water supply controller 500. The hot water supply control device 308 includes, for example, a measuring unit 308a, a control unit 308b, and a communication unit 308c. The measuring unit 308a measures various temperatures by inputting signals detected by the temperature sensors 310 and 312 and performs calculations based on the input signals. The communication unit 308c is connected to each part of the hot water supply unit 300 via communication lines and sends and receives various data and information.The communication unit 308c receives an input of a hot water supply request issued by the hot water supply controller 500. The control unit 308b controls the electric heater 306 based on the measured temperature and the hot water supply request. Specifically, the control unit 308b issues a hot water supply request when it detects that the water temperature in the hot water storage tank 304 has decreased based on the information output from the hot water controller 500. For example, when a hot water supply setting temperature is set to 55°C and a water temperature is 45°C or less based on a detection signal from the temperature sensor 310, resulting in a water temperature 10°C lower than the hot water supply setting temperature, the control unit 308b issues the hot water supply request.

[0021] The air conditioning controller 400 is, for example, a remote control for an air conditioner, but is not limited to this, and may be a tablet, a personal computer, or a smartphone on which application software is installed. The air conditioning controller 400 includes, for example, an input unit 410, a communication unit 420, and a display unit 430. The input unit 410 is an operation interface that receives user operations. The display unit 430 displays various information about the air conditioning system, such as the input results based on the operations and the state of the air conditioning unit 200. The communication unit 420 transmits information based on the operations received from the input unit 410 to the air conditioning control device 206 and the heat source control device 112.

[0022] The hot water supply controller 500 is, for example, but is not limited to, a remote control for the hot water supply and may be a tablet, a personal computer, or a smartphone on which application software is installed. The hot water supply controller 500 includes, for example, an input unit 510, a communication unit 520, and a display unit 530. The input unit 510 is an operation interface that receives user operations. The display unit 530 displays various information about the hot water supply, such as the input results based on operations and the status of the hot water supply unit 300. The communication unit 520 sends information based on the operation received from the input unit 510 to the hot water supply control device 308 and the heat source control device 112.

[0023] The air conditioner supplies a cooling request or a heating request selected by the air conditioning units 200A and 200B to the heat source control device 112 and supplies a hot water request of the hot water supply unit 300 to the heat source control device 112. Thereby, the air conditioner controls each part of the heat source unit 100, the air conditioning unit 200, and the hot water supply unit 300 through the heat source control device 112.

[0024] The following describes an operating mode of the air conditioning system described above.

[0025] The air conditioner in the embodiment performs a hot water supply operation mode according to a hot water supply request set by the hot water supply controller 500, a cooling operation mode according to a cooling request set by the air conditioning controller 400, and a heating operation mode according to a heating request set by the air conditioning controller 400. An operation of the air conditioner in each operation mode and the flow state of a refrigerant are described below. When a hot water supply request and a cooling request are given simultaneously, an alternating operation is performed in which a cooling operation and a hot water supply operation are alternately performed, and the cooling operation is resumed when there is no longer a hot water supply request.When a hot water demand and a heating demand are simultaneously issued, an alternating operation is performed in which a heating operation and a hot water supply operation are performed alternately, and the heating operation is resumed when the hot water demand is no longer present. In principle, an air conditioner performs a hot water supply operation with priority over a cooling operation and a heating operation. The reason why the hot water supply operation is performed with priority is to prevent the occurrence of a hot water shortage in which the hot water storage tank 304 runs out of hot water.

[0026] First, a hot water supply operation will be described. During the hot water supply operation, the heat source control device 112 connects the outlet side of the compressor 102 and the refrigerant line 1 by controlling the four-way valve 104, and connects a suction side of the compressor 102 and a gas side of the heat source-side heat exchanger 106. Further, the heat source control device 112 performs control such that the pressure reducing mechanisms 130a and 130b are set to be in a closed state (closed circuit). A high-temperature and high-pressure refrigerant gas discharged from the compressor 102 flows into the heat exchanger 302 after passing through the refrigerant line 1c via the four-way valve 104. As a result, a gas heats the water in the hot water storage tank 304 via a wall surface of the hot water storage tank 304.Thereafter, the refrigerant flows out of the heat exchanger 302, is expanded by the pressure reducing mechanism 130c via the refrigerant line 2c, and flows into the heat source-side heat exchanger 106. As a result, the refrigerant becomes a low-pressure gaseous refrigerant through heat exchange with the air (also referred to as heat source air) supplied from the heat source-side blower 108. The low-pressure gaseous refrigerant flowing out of the heat source-side heat exchanger 106 passes through the accumulator 110 via the four-way valve 104 and is then re-sucked into the compressor 102. In the hot water supply operation, heat can be exchanged between the refrigerant and a water circuit (not shown), and heat can be exchanged between the water circuit and the water in the hot water storage tank 304.

[0027] During hot water supply operation, the heat source control device 112 performs control so that the operating frequency of the compressor 102 becomes the maximum frequency. Furthermore, the heat source control device 112 performs control so that the rotation speed of the heat source-side fan 108 is set to a set value. Furthermore, the heat source control device 112 controls the opening degree of the pressure reducing mechanism 130c so that the outlet temperature of the pressure reducing mechanism 130c becomes a set value. The set value of the outlet temperature is, for example, a saturation temperature of the temperature sensor 122 provided on an outlet side of the compressor 102.

[0028] Next, a cooling operation will be described. The heat source control device 112 controls the four-way valve 104 to connect the discharge side of the compressor 102 and the gas side of the heat source-side heat exchanger 106, and to connect the suction side of the compressor 102 and a downstream side of the accumulator 110.

[0029] A high-temperature, high-pressure gas refrigerant discharged from the compressor 102 flows into the heat-source-side heat exchanger 106 via the four-way valve 104 and radiates heat to the heat-source air blown by the heat-source-side blower 108, thereby converting the refrigerant into a high-pressure liquid refrigerant. The high-pressure liquid refrigerant then flows out of the heat-source-side heat exchanger 106 and is decompressed into a low-pressure two-phase refrigerant by the pressure-reducing mechanisms 130a and 130b. The low-pressure two-phase refrigerant flows out of the heat-source unit 100 and into the air-conditioning units 200A and 200B via the refrigerant lines 7a and 7b. Thereafter, the two-phase low-pressure refrigerant is cooled by the room air in the respective heat exchangers 202 and becomes a low-pressure gaseous refrigerant.The low-pressure gaseous refrigerant flows from the air conditioning units 200A and 200B, via the refrigerant lines 1a and 1b into the heat source unit 100, into the accumulator 110, and is sucked again into the compressor 102.

[0030] During cooling operation, the heat source control device 112 controls the opening degree of the pressure reduction mechanisms 130a and 130b to set an outlet temperature to a set value. Furthermore, the heat source control device 112 controls the operating frequency of the compressor 102 to set an evaporation temperature to a set value. The evaporation temperature is the minimum temperature between a temperature detected by the temperature sensor 210 and a temperature detected by the temperature sensor 212. The heat source control device 112 controls the heat source-side fan 108 to set a condensation temperature to a set value. The condensation temperature is, for example, a temperature detected by the temperature sensor 126.

[0031] Next, an operating state of the heating operation will be described. The heat source control device 112 controls the four-way valve 104 to connect the discharge side of the compressor 102 and the refrigerant line 1, and to connect the suction side of the compressor 102 and the gas side of the heat source-side heat exchanger 106.

[0032] The high-temperature, high-pressure refrigerant gas discharged from the compressor 102 flows through the refrigerant lines 1a and 1b via the four-way valve 104 and then flows into the heat exchanger 202 to heat the indoor air, becoming a high-pressure liquid refrigerant. The high-pressure liquid flows out of the air conditioning units 200A and 200B, is decompressed by the pressure reducing mechanisms 130a and 130b, and flows into the heat source-side heat exchanger 106. The high-pressure liquid exchanges heat with the heat source air supplied from the heat source-side blower 108 and becomes a low-pressure refrigerant gas. The low-pressure gaseous refrigerant flowing out of the heat source-side heat exchanger 106 then flows through the accumulator 110 via the four-way valve 104 and is then sucked into the compressor 102 again.

[0033] During a heating operation, the heat source control device 112 controls the opening degrees of the pressure reducing mechanisms 130a and 130b so that an outlet temperature becomes a set value, and performs control to set the pressure reducing mechanism 130c to be in a closed state (closed loop). Furthermore, the heat source control device 112 controls the operating frequency of the compressor 102 so that a condensing temperature becomes a set value. The condensing temperature is obtained as the maximum temperature among a temperature detected by the temperature sensor 210 and a temperature detected by the temperature sensor 212.

[0034] Next, a heating operation using the electric heater 306 will be described. The electric heater 306 is installed so that it is immersed inward from the inner wall surface of the hot water storage tank 304. The hot water supply unit 300 heats water in the hot water storage tank 304 by electrifying the electric heater 306. Due to this, the air conditioner can heat water by electrifying the electric heater 306 even when the heat source unit 100 is not performing a hot water supply operation.

[0035] For example, if the hot water supply controller 500 sets a hot water temperature such that it is difficult to complete heating in the hot water supply operation by the heat source unit 100, the air conditioner starts a heating operation using the electric heater 306 when a water temperature increases to a set value during the hot water supply operation of the heat source unit 100. The set value for starting the heating operation by the electric heater 306 is stored in the storage unit 112d. During the heating operation using the electric heater 306, a hot water supply request issued from the hot water supply controller 308 to the heat source controller 112 remains issued.If no air conditioning request is issued to the heat source control device 112 during the heating operation with the electric heater 306, the heat source unit 100 is stopped. On the other hand, if an air conditioning request is issued to the heat source control device 112 from one of the air conditioning units 200A and 200B, the heat source control device 112 restarts an air conditioning operation by the heat source unit 100 even if the hot water supply request continues to be issued. This allows the air conditioner to restart the air conditioning operation at an early stage, thus preventing indoor comfort from being impaired.

[0036] For example, the set point (threshold) for starting heating by the electric heater 306 during the hot water supply operation is set to 55°C. This is because when R32 or R410A is used as the refrigerant gas, the refrigerant pressure is close to 4.0 MPaG and close to a maximum allowable refrigerant pressure of the heat source unit 100 when the heating temperature reaches 55°C.

[0037] Fig. 3 is a flowchart showing an example of a specific operation method of the air conditioner according to the embodiment. The air conditioner performs a heating operation based on a heating request issued from the air conditioning controller 400 (step S10). During the heating operation, the water temperature in the hot water storage tank 304 decreases, and a hot water supply request is issued from the hot water supply control device 308 to the heat source control device 112 (step S12). A set value of a hot water supply temperature (also referred to as a target hot water supply temperature) corresponding to the hot water supply request is, for example, 60°C. In response to receiving the hot water supply request, the heat source control device 112 interrupts the heating operation and starts a hot water supply operation by the heat source unit 100 (step S14).

[0038] The heat source control device 112 determines whether a hot water supply request time of the heat source unit 100 is equal to or less than a maximum hot water supply period (first continuous operation time) when the heating request is given (step S16). The maximum hot water supply period when the heating request is given is also referred to as the threshold value T max (H). When the hot water supply operating time of the heat source unit 100 is equal to or less than the threshold value T max(H) (step S16: Yes), the heat source control device 112 determines whether a water temperature in the hot water storage tank 304 is equal to or lower than a threshold temperature (e.g., 55°C) (step S18). The threshold water temperature is, for example, 55°C, which is lower than a target hot water supply temperature of 60°C. The difference between the threshold temperature and the target hot water supply temperature is a temperature range that can be increased by heating the electric heater 306 and can be arbitrary. If the water temperature in the hot water storage tank 304 reaches a threshold (step S18: Yes), the heat source control device 112 returns to step S16 for processing.If the water temperature in the hot water storage tank 304 is not the threshold (step S18: No), the heat source control device 112 starts heating (heating operation) by the electric heater 306 and starts (permits) a heating operation by the heat source unit 100 (step S24). The heat source control device 112 stops the electric heater 306 and resumes the heating operation when there is no longer a hot water supply demand during the heating operation (step S26).

[0039] In this way, when the water temperature increases due to the hot water supply operation and reaches the threshold temperature, the heat source control device 112 stops the hot water supply operation of the heat source unit 100 and starts heating by the electric heater 306. This allows the heat source control device 112 to restart a heating operation by the heat source unit 100. Thereafter, when the water temperature in the hot water storage tank 304 reaches a target hot water supply temperature and there is no longer a hot water demand, the air conditioner stops heating by the electric heater 306 and resumes the heating operation.

[0040] According to the air conditioner, a hot water request takes priority over an air conditioning request, and therefore, air conditioning operation cannot be performed during a period when a hot water request is issued, but air conditioning operation can be restarted before the water temperature reaches 60°C. Therefore, according to the air conditioner, it is possible to suppress deterioration of indoor comfort.

[0041] If a requested hot water supply time of the heat source unit 100 is not equal to or less than the threshold T max(H) (step S16: No), the heat source control device 112 interrupts the hot water supply operation by the heat source unit 100 and restarts a heating operation (step S20). Thereafter, the heat source control device 112 determines whether a heating operation time of the heat source unit 100 is equal to or less than a maximum continuous time of the air conditioning (step S22). If the heating operation time is less than or equal to the maximum continuous time of the air conditioning at a hot water supply request (step S22: Yes), the heat source control device 112 maintains the interruption of the hot water supply operation and the continuation of the heating operation by the heat source unit 100.If the heating operation time is not equal to or less than the maximum continuous time of the air conditioning when the hot water supply is requested (step S22: No), the heat source control device 112 interrupts the heating operation and restarts the hot water supply operation (step S14).

[0042] In step S18, it is determined whether to start a heating operation using the electric heater 306 based on the water temperature in the hot water storage tank 304, but the present disclosure is not limited thereto. The air conditioner may determine whether to switch from the hot water supply operation of the heat source unit 100 to the heating operation using the electric heater 306 when the condensing temperature during the hot water supply operation becomes equal to or higher than a set value. The set value of the condensing temperature during the hot water supply operation is, for example, 58°C. The condensing temperature during the hot water supply operation is a saturation temperature at a pressure detected by the pressure sensor 120 (high pressure sensor) during the hot water supply operation.At low outside air temperature, the pressure of a refrigerant sucked into the compressor 102 decreases, and the lower the outside air temperature, the lower the condensation temperature becomes, regardless of the water temperature in the hot water storage tank 304. Therefore, the heat source unit 100 can continue the hot water supply operation for a longer period of time by determining whether to switch from the hot water supply operation of the heat source unit 100 to the heating operation using the electric heater 306 based on whether the condensation temperature has exceeded the set value during the hot water supply operation. As a result, according to the air conditioner, it is possible to reduce the amount of energy consumed for heating water.

[0043] When the heating operation using the electric heater 306 is started based on the fact that the condensing temperature during the hot water supply operation becomes equal to or higher than the set value in step S18, the heating capacity for water in the hot water storage tank 304 decreases as the rotation frequency of the compressor 102 decreases, and thus the condensing temperature is reduced during the hot water supply operation. As the condensing temperature decreases during the hot water supply operation, a hot water supply operation time becomes longer, and the indoor temperature may change, resulting in a decrease in comfort. The lowest value of the rotation frequency of the compressor 102 during the hot water supply operation is made larger than the lowest value of the rotation frequency during an air conditioning operation.This allows the air conditioner to prevent the time until the condensing temperature reaches the set point during hot water supply operation from becoming longer, thereby suppressing a reduction in indoor comfort.

[0044] The air conditioner suppresses a decrease in indoor comfort by restarting an air-conditioning operation while the electric heater 306 starts a heating operation. However, when the water temperature in the hot water storage tank 304 is low and the hot water supply operation period of the heat source unit 100 becomes longer, indoor comfort may decrease. To prevent this, the air conditioner interrupts the hot water supply operation of the heat source unit 100 and restarts the heating operation when the hot water supply operation period of the heat source unit 100 reaches a continuous operation time of the hot water supply continuous operation time when a heating request is given (steps S18 and S20).Thereafter, when the heating operation period reaches the maximum continuous time of air conditioning, if a hot water supply request is given, the air conditioner restarts the heating operation and restarts the hot water supply operation of the heat source unit 100. In this way, the air conditioner can suppress a decrease in indoor comfort by alternately repeating the heating operation and the hot water supply operation. However, when a load of the heating operation is high, the change rate of the indoor temperature is high during the interruption of the heating operation, and thus the air conditioner can restart the heating operation when the electric heater 306 starts the heating operation. Thereby, according to the air conditioner, it is possible to further suppress a decrease in indoor comfort even when the load of the air conditioning operation is high.

[0045] Fig. Fig. 4 is a diagram showing an operation of the air conditioner according to the embodiment, wherein (a) is a diagram showing temporal changes in an operation mode of the heat source unit 100, (b) is a diagram showing temporal changes in the water temperature in the hot water storage tank 304, and (c) is a diagram showing temporal changes in an operation of the electric heater 306. The operation of the air conditioner is described together with the above-described operation in Fig. 3 described.

[0046] The air conditioner suppresses a decrease in indoor comfort by allowing (restarting) a heating operation after starting a heating operation of the electric heater 306 (step S24). However, if the rate of increase of the water temperature in the electric heater 306 is slow, it takes a while to restart a hot water supply operation, resulting in a decrease in indoor comfort. On the other hand, the air conditioner starts a hot water supply operation when a hot water request is issued (t1) while performing a heating operation in response to the hot water request, and the air conditioner continues the hot water supply operation until a threshold T max (H) is reached when the water temperature in the hot water storage tank 304 is 55 °C or less (steps S16 and S18). When the hot water supply operating time exceeds the threshold T max(H) (t2), the hot water supply operation is interrupted and a heating operation is restarted (step S20). After that, if a heating operation time does not reach the threshold THmax, the heating operation is resumed (step S22). When the heating operation time reaches the threshold THmax (t3), the heating operation is interrupted and the hot water supply operation is restarted (step S14). By repeating such operations, the air conditioner can alternately perform the heating operation and the hot water supply operation.

[0047] When the heating operation and the hot water supply operation are alternately performed, when the water temperature in the hot water storage tank 304 reaches 55°C (t4, step S18), the electric heater 306 is switched to an on-state to start a heating operation and restart the heating operation (step S24). When the electric heater 306 is turned on, the water temperature in the hot water storage tank 304 continues to rise, and when the water temperature reaches 60°C, which corresponds to a target hot water supply temperature (t5), there is no longer a hot water demand, and heating of the electric heater 306 ends (step S26). After that, the air conditioner continues the heating operation until there is no longer a hot water demand.

[0048] As described above, according to the air conditioner, the water temperature does not reach the target hot water supply temperature even when a heating operation and a hot water supply operation are performed alternately, and a heating operation can be restarted by heating with the electric heater 306 even if the hot water supply time becomes longer. This allows the air conditioner to prevent both a decrease in the amount of hot water in the hot water storage tank 304 and a decrease in indoor comfort.

[0049] On the other hand, the air conditioner prevents heating by the electric heater 306 when performing an alternating heating operation in which the heating operation and the hot water supply operation are alternately performed (step S20). The air conditioner prevents heating by the electric heater 306 when performing an alternating cooling operation in which the cooling operation and the hot water supply operation are alternately performed (step S20). This allows the air conditioner to heat with lower power consumption than when the electric heater 306 is used for heating and improves energy saving performance. As a result, according to the air conditioner, it is possible to completely suppress the decrease in the amount of hot water in the hot water storage tank 304, suppress the decrease in indoor comfort, and improve energy saving performance.

[0050] In the embodiment described above, the heating operation and the hot water supply operation are alternately performed (first alternating operation), but a “heating request” can be read as a “cooling request”, a “heating operation” can be read as a “cooling operation”, an “alternating operation of alternately performing a heating operation and a hot water supply operation” can be read as an “alternating operation in which a cooling operation and a hot water supply operation are alternately performed (second alternating operation)”, and a “maximum continuous time of hot water supply when a heating request is given (threshold T max (H))” can be defined as “maximum continuous time of hot water supply when a cooling request is given (threshold T max(C), second continuous operating time)." This allows the air conditioning system to prevent both a reduction in the amount of hot water in the hot water storage tank 304 and a reduction in indoor comfort, even when a cooling demand and a hot water demand exist simultaneously.

[0051] A continuous operating time of a hot water supply system in alternating operation is described below.

[0052] Whether the air conditioner's heating load is higher in winter or cooling load is higher in summer depends on the air conditioner's installation environment. For example, in summer, when sunlight penetrates well into a room and the average outdoor air temperature is high, the rate of increase in room temperature increases during a cooling interruption period in alternating mode. Conversely, in winter, when the average outdoor air temperature is low, the rate of decrease in room temperature increases during a heating interruption period in alternating mode.

[0053] Due to this, the air conditioning system carries out a control so that the threshold value T max (H) in the alternating operation of alternately performing a heating operation and a hot water supply operation (step S14 to step S22) deviates from the threshold value T max(C) in the alternating operation of alternately performing a cooling operation and a hot water supply operation (step S14 to step S22). For example, the air conditioner sets the threshold value T max (H) and the threshold value T max (C) to different times based on the installation environment of the air conditioner and stores them in the storage unit 112d. When the air conditioner is performing a heating operation, the air conditioner reads in step S16 in Fig. 3 Information about the threshold T max (H) from the storage unit 112d and limits a continuous operating time of a hot water supply operation. When the air conditioner performs a cooling operation, the air conditioner reads information about the threshold value T max (C) from the storage unit 112d in step S16 in Fig. 3 and limits the continuous operating time of a hot water supply operation. This allows the air conditioner to separately set the maximum continuous operating time of hot water supply for heating and cooling operation in alternating mode based on the air conditioner's installation environment. This allows the air conditioner to provide indoor comfort in both summer and winter.

[0054] For example, assume that the installation environment in winter (heating season) has an indoor temperature of 20°C and an outdoor air temperature of 7°C, the temperature difference between the indoor temperature and the outdoor air temperature is 13°C. For example, assume that the installation environment in summer (cooling season) has an indoor temperature of 27°C and an outdoor air temperature of 35°C, the temperature difference between the indoor temperature and the outdoor air temperature is 8°C. In this way, the temperature difference between indoor and outdoor is higher in winter than in summer, and thus the air conditioning load in heating mode is higher than in cooling mode. Due to this, the air conditioner sets the threshold T max (H) so that it is smaller than the threshold value T max (C). This can cause air conditioning to reduce indoor comfort during the heating season when there is a large temperature difference between indoor and outdoor.

[0055] Fig. Figure 5 is a diagram showing an example of a relationship between an outside air temperature and a threshold T max (H) in the embodiment. The air conditioner can set the threshold T max (H) based on an outside air temperature. The air conditioner sets the threshold T max (H) so that it is smaller as the outdoor air temperature decreases. This is because the lower the outdoor air temperature, the higher the heating load and the greater the likelihood of the room temperature decreasing during hot water supply operation.

[0056] Fig. 6 is a diagram showing an example of a relationship between an outside air temperature and a threshold T max (C) in the embodiment. The air conditioner can set the threshold T max(C) based on the outside air temperature. The air conditioner sets the threshold T max (C) to decrease as the outside air temperature increases. This is because the higher the outside air temperature, the higher the cooling load and the greater the likelihood of the room temperature increasing during hot water supply operation.

[0057] The air conditioner stores the relationship between the outside air temperature and the Fig. 5 shown threshold T max (H) and the relationship between the outside air temperature and the Fig. 6 shown threshold T max (C) in the storage unit 112d. This allows the air conditioner to limit the hot water supply operating time in alternating operation to a value corresponding to a detected value of the outside air temperature. The threshold value T max (H) and the threshold T max(C) for the outside air temperature are stored in the storage unit 112d of the heat source control device 112, and the threshold value T max (H) and the threshold T max (C) can be determined in relation to the detected value of the outside air temperature. The air conditioner can both determine the threshold value T max (H) and the threshold value T max (C) based on the outside air temperature or change the threshold T max (H) and / or the threshold value T max (C) change.

[0058] In particular, the air conditioner can store the relationships of the following equations and coefficients a, b, c, and d. The coefficients a and b are calculated based on a change in T max (H) is set in relation to the outside air temperature as in Fig. 5. The coefficients c and d are calculated based on a change in T max (C) set in relation to the outside air temperature as in Fig.6 shown. Tmax(H)=b+a×outside air temperature Tmax(C)=d−c×outside air temperature

[0059] The air conditioner can set a suitable hot water supply operating time according to changes in the air conditioning load by setting the threshold value T max (H) and the threshold T max (C) based on the outside air temperature.

[0060] When the indoor temperature reaches the set temperature during the alternating operation in step S22, the air conditioner can restart the hot water supply operation even if the heating operation time does not reach the maximum continuous air conditioning time. This allows the air conditioner to restart the hot water supply operation at an early stage without waiting for the maximum continuous air conditioning time to be reached. As a result, the air conditioner can suppress a decrease in the amount of hot water in the hot water storage tank 304.

[0061] In step S18, the air conditioner determines a heating start timing of the electric heater 306 based on a water temperature in the hot water storage tank. However, the air conditioner may instead determine the heating start timing of the electric heater 306 based on a hot water supply condensing temperature. The hot water supply condensing temperature is a saturation temperature at a pressure detected by the pressure sensor 120 (high pressure sensor) during a hot water supply operation. As the water temperature in the hot water storage tank 304 increases during the hot water supply operation, the hot water supply condensing temperature also increases. The air conditioner starts heating by the electric heater 306 when the hot water supply condensing temperature becomes equal to or higher than the condensing temperature (threshold, e.g., 60°C) at which the electric heater 306 starts heating.Since an upper limit for the operating pressure in the heat source unit 100 is set, the air conditioner can continue the hot water supply operation to the extent that the heat source unit 100 can operate by determining whether to start heating the electric heater 306 using the hot water supply condensing temperature. This allows the air conditioner to further suppress power consumption during the hot water supply operation.

[0062] Furthermore, in the air conditioner, the minimum frequency of the compressor 102 during the hot water supply operation is set higher after step S14 than the minimum frequency of the compressor 102 during the air conditioning operation after step S10. In the air conditioner, the minimum frequency of the compressor 102 during the hot water supply operation can be set to be higher than the minimum frequency of the compressor 102 during the cooling operation state and / or the heating operation state. The operating frequency of the compressor 102 increases with increasing air conditioning load. On the other hand, the air conditioner sets the minimum frequency at which the compressor 102 operates to be higher during the hot water supply operation than during the air conditioning operation, for example, even when the outside air temperature is the same during the heating operation and the cooling operation.

[0063] When the operating frequency of the compressor 102 decreases during the hot water supply operation, the heating capacity for heating is reduced, and it takes a long time to complete the hot water supply. On the other hand, it is necessary to be able to reduce the minimum frequency so that the operating frequency of the compressor 102 is suppressed when the load is low during the air conditioning operation. According to the air conditioner, the minimum frequency of the compressor 102 is set high during the hot water supply operation, and thus the heating capacity can be prevented from becoming extremely low. Furthermore, according to the air conditioner, it is possible to start heating by the electric heater 306 at an early stage by raising the hot water supply condensing temperature slightly earlier. By doing so, according to the air conditioner, it is possible to suppress a decrease in the amount of hot water in the hot water storage tank 304.

[0064] As described above, according to the air conditioning system, it is possible to provide a hot water supply air conditioner that achieves both air conditioning performance and hot water supply performance and has high user satisfaction even if there are seasonal changes in the installation environment.

[0065] Although the embodiment of the present disclosure has been described above in detail with reference to the drawings, the specific configuration is not limited to the above-described embodiment, and designs and the like that fall within the scope of the spirit of the present disclosure are also included. List of reference symbols 1, 1a, 1b, 1c refrigerant line 2a, 2b, 2c refrigerant line 7a, 7b refrigerant line 100 heat source unit 102 Compressor 104 Four-way valve 106 Heat source side heat exchanger 108 Heat source side fan 110 accumulator 112 Heat source control device 112a measuring unit 112b Communication unit 112c control unit 112d storage unit 120 pressure sensor 122, 124, 126, 128 Temperature sensor 130a, 130b, 130c Pressure reduction mechanism 200, 200A, 200B air conditioning unit 202 heat exchangers 204 air blower 206 Climate control device 206a measuring unit 206b control unit 206c communication unit 210, 212, 214 temperature sensor 300 hot water supply unit 302 heat exchangers 304 hot water storage tanks 306 Electric Heater 308 Hot water supply control device 308a measuring unit 308b control unit 308c communication unit 310 temperature sensor 312 Temperature sensor 400 climate control 410 input unit 420 communication unit 430 display unit 500 hot water supply control 510 input unit 520 communication unit 530 display unit QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] WO 2018 / 189942

[0004]

Claims

[1] Air conditioning system, comprising: a heat source device comprising a refrigerant circuit in which a refrigerant circulates; an air conditioning unit configured to perform a heating operation and a cooling operation by heat exchange between the refrigerant and indoor air; a hot water supply unit including a hot water storage tank and configured to perform a hot water supply operation by heating with the refrigerant; and a control unit configured to perform a first alternating operation in which the heating operation and the hot water supply operation are alternately performed when a heating request and a hot water supply request are issued simultaneously, and to perform a second alternating operation in which the cooling operation and the hot water supply operation are alternately performed when a cooling request and the hot water supply request are issued simultaneously, wherein the control unit is configured to perform control such that a first continuous operation time of the hot water supply operation in the first alternating operation is different from a second continuous operation time of the hot water supply operation in the second alternating operation. [2] The air conditioner according to claim 1, wherein the control unit is configured to set the first continuous operation time shorter than the second continuous operation time. [3] The air conditioner according to claim 1 or 2, wherein the control unit is configured to change the first continuous operation time and / or the second continuous operation time based on an outside air temperature. [4] Air conditioning system according to claim 1 or 2, wherein the hot water supply unit comprises a heating unit, and wherein the control unit is configured to cause the heating unit to start heating and start the heating operation in the first alternating operation, and to cause the heating unit to start heating and start the cooling operation in the second alternating operation. [5] The air conditioner according to claim 4, wherein the control unit is configured to cause the heating unit to start heating when a water temperature in the hot water storage tank reaches a threshold value. [6] The air conditioner according to claim 4, wherein the control unit is configured to cause the heating unit to start heating when a condensing temperature of the refrigerant reaches a threshold during the hot water supply operation. [7] The air conditioner according to claim 5 or 6, wherein the control unit is configured to prevent the heating unit from starting heating when the heating operation is performed in the first alternating operation or when the cooling operation is performed in the second alternating operation. [8] The air conditioner according to claim 7, wherein the control unit is configured to allow the heating unit to perform the heating operation when the heating operation is performed in the first alternating operation or the cooling operation is performed in the second alternating operation and an indoor temperature reaches a target temperature. [9] Air conditioning system according to claim 1 or 2, wherein the heat source device comprises a compressor, wherein a minimum frequency of the compressor in hot water supply mode is greater than a minimum frequency of the compressor in heating mode, and where the minimum frequency of the compressor in hot water supply mode is greater than a minimum frequency of the compressor in cooling mode. [10] A method for air conditioning in an air conditioning system comprising a heat source device including a refrigerant circuit in which a refrigerant circulates, an air conditioning unit configured to perform a heating operation and a cooling operation by heat exchange between the refrigerant and an indoor air, and a hot water supply unit including a hot water storage tank and configured to perform a hot water supply operation by heating with the refrigerant, the method for air conditioning comprising: Performing a first alternating operation in which the heating operation and the hot water supply operation are performed alternately when a heating request and a hot water supply request are issued simultaneously; and Performing a second alternating operation in which the cooling operation and the hot water supply operation are carried out alternately when a cooling request and the hot water supply request are issued simultaneously, wherein a first continuous operation time of the hot water supply operation in the first alternating operation is different from a second continuous operation time of the hot water supply operation in the second alternating operation.

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