WO2017104086A1

WO2017104086A1 - Air conditioner

Info

Publication number: WO2017104086A1
Application number: PCT/JP2015/085587
Authority: WO
Inventors: 将一青木
Original assignee: 三菱電機株式会社
Priority date: 2015-12-18
Filing date: 2015-12-18
Publication date: 2017-06-22
Also published as: CN206637800U; JPWO2017104086A1; JP6501912B2

Abstract

This air conditioner has a refrigerant circuit in which a compressor, a flow passage switching apparatus, a heat source side heat exchanger, an expansion apparatus, and a use side heat exchanger are connected through refrigerant piping to circulate a refrigerant. The air conditioner is provided with an indoor machine accommodating the use side heat exchanger, and executes a dew condensation prevention operation of estimating a possibility of occurrence of dew condensation by using a detection result of a room temperature sensor, a detection result of a humidity sensor, and a detection result of a heat exchange temperature sensor, and of switching, when there is a possibility that dew condensation will occur, the flow passage switching apparatus to bring the detection result of the heat exchange temperature sensor closer to the detection result of the room temperature sensor.

Description

Air conditioner

This invention relates to an air conditioner that prevents the occurrence of condensation.

Conventionally, there has been known an air conditioner that estimates the possibility of the occurrence of condensation and starts the condensation prevention operation when the possibility of the occurrence of condensation is estimated (see, for example, Patent Document 1). In the conventional air conditioner described in Patent Literature 1, in the dew condensation prevention operation, the indoor unit performs a blowing operation or performs an internal drying operation in a heating cycle.

JP 2012-207811 A

However, in the conventional air conditioner described in Patent Document 1, in the dew condensation prevention operation, the stopped indoor unit suddenly performs the air blowing operation, so that the user feels uncomfortable. Furthermore, when the indoor unit performs the air blowing operation, the indoor temperature changes, and indoor comfort may be reduced. In addition, in the condensation prevention operation, when the internal drying operation in the heating cycle is performed, the operation in the heating cycle is executed until the interior of the indoor unit is dried, so that power consumption increases.

The present invention has been made against the background of the above problems, and an object thereof is to obtain an air conditioner capable of suppressing the occurrence of condensation without impairing the comfort of the user.

An air conditioner according to the present invention includes an air conditioner having a refrigerant circuit in which a compressor, a flow path switching device, a heat source side heat exchanger, an expansion device, and a use side heat exchanger are connected by a refrigerant pipe and the refrigerant circulates. The indoor unit includes an indoor unit that is installed indoors and accommodates the usage-side heat exchanger, and the indoor unit detects an indoor unit fan that blows air to the usage-side heat exchanger, and detects the temperature in the room A room temperature sensor, a heat exchange temperature sensor that detects the temperature of the use side heat exchanger, a humidity sensor that is housed in the indoor unit and detects the humidity of air before heat exchange with the use side heat exchanger, The indoor unit has a detection result detected by the room temperature sensor and a detection result detected by the humidity sensor during the operation stop of the indoor unit in which the indoor unit fan has stopped blowing. A detection result detected by the heat exchanger temperature sensor; Thus, the possibility of condensation is estimated, and when condensation is likely to occur, the flow switching device is switched to bring the detection result of the heat exchange temperature sensor closer to the detection result of the room temperature sensor. The dew condensation prevention operation is executed.

The air conditioner according to the present invention prevents the occurrence of condensation by bringing the temperature inside the indoor unit close to the temperature in the room, thereby preventing the occurrence of condensation without impairing the user's comfort. A possible air conditioner is obtained.

It is the figure which described typically an example of the structure of the air conditioner which concerns on Embodiment 1 of this invention. It is a figure explaining an example of a structure of the indoor unit of FIG. 1, and the control apparatus of an indoor unit. It is a figure explaining an example of operation | movement of the dew condensation prevention driving | operation of the air conditioner described in FIG.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and the description thereof is omitted or simplified as appropriate. In addition, the shape, size, arrangement, and the like of the configuration described in each drawing can be changed as appropriate within the scope of the present invention.

Embodiment 1 FIG.
[Air conditioner]
FIG. 1 is a diagram schematically illustrating an example of the configuration of an air conditioner according to Embodiment 1 of the present invention, and FIG. 2 is a diagram illustrating the configuration of the indoor unit and the indoor unit control device illustrated in FIG. It is a figure explaining an example. As shown in FIG. 1, an air conditioner 1 according to an example of this embodiment performs indoor air conditioning inside a room and has a refrigerant circuit 1A in which a refrigerant circulates. The refrigerant circuit 1A is formed by connecting the indoor unit 100A, the indoor unit 100B, and the outdoor unit 200 with a refrigerant pipe. The indoor unit 100A and the indoor unit 100B are connected in parallel to each other. In the example of FIG. 1, one outdoor unit 200 is described. However, the air conditioner 1 of this embodiment may include two or more outdoor units. In the example of FIG. 1, two indoor units, the indoor unit 100A and the indoor unit 100B, are described, but the air conditioner 1 of this embodiment has one or three or more indoor units. It may be a thing.

[Outdoor unit]
The outdoor unit 200 is installed outside the room, for example, and functions as a heat source unit that wastes or supplies the heat of the air conditioning. The outdoor unit 200 contains, for example, a compressor 202, a flow path switching device 204, and a heat source side heat exchanger 206 that are connected by refrigerant piping.

The compressor 202 sucks and compresses the refrigerant and discharges it in a high temperature / high pressure state. The compressor 202 is, for example, an inverter compressor that is controlled by an inverter, and can change the capacity (the amount of refrigerant sent out per unit time) by arbitrarily changing the operating frequency. The flow path switching device 204 is composed of, for example, a four-way valve or the like, and switches the flow path of the refrigerant circuit 1A between the cooling operation and the heating operation. For example, the heat source side heat exchanger 206 exchanges heat between the refrigerant and air.

Further, the outdoor unit 200 includes a heat source side heat exchanger fan 208 and an outdoor unit control device 250. The heat source side heat exchanger fan 208 blows air to the heat source side heat exchanger 206 and is installed, for example, in the vicinity of the heat source side heat exchanger 206. The outdoor unit control device 250 controls the outdoor unit 200 and includes, for example, an analog circuit, a digital circuit, a CPU, or a combination of two or more thereof.

As shown in FIG. 2, the outdoor unit control device 250 includes, for example, an outdoor unit control unit 252 and an outdoor unit communication unit 254. The outdoor unit control unit 252 controls, for example, the operating frequency of the compressor 202, controls the switching state of the flow path switching device 204, and controls the rotation speed of the heat source side heat exchanger fan 208. In addition, the outdoor unit control unit 252 can communicate with the indoor unit 100A and the indoor unit 100B via the outdoor unit communication unit 254.

[Indoor unit]
As shown in FIG. 1, the indoor unit 100A and the indoor unit 100B are installed inside a room and supply conditioned air to the room. For example, the indoor unit 100A and the indoor unit 100B are installed in different rooms, but the indoor unit 100A and the indoor unit 100B may be installed in the same room.

The indoor unit 100A has a use-side heat exchanger 102A and an expansion device 104A connected by refrigerant piping. The usage-side heat exchanger 102A exchanges heat between the refrigerant and air. The expansion device 104A depressurizes the refrigerant, and is, for example, an electronic expansion valve that can adjust the opening degree. Note that the expansion device 104A according to this embodiment may include a capillary tube and an on-off valve whose opening degree cannot be adjusted.

The indoor unit 100A includes a louver 107A, a heat exchange temperature sensor 130A, a room temperature sensor 132A, a humidity sensor 134A, an input device 136A, an indoor unit fan 140A, and an indoor unit control device 150A. Louver 107A is installed at air outlet 106A of indoor unit 100A and opens and closes air outlet 106A. The heat exchanger temperature sensor 130A detects the temperature of the use side heat exchanger 102A, and is attached to the use side heat exchanger 102A, for example. The room temperature sensor 132A detects the temperature of the indoor air, and is disposed, for example, in the air path between the suction port (not shown) of the indoor unit 100A and the use side heat exchanger 102A. The humidity sensor 134A is housed inside the indoor unit 100A and detects the humidity of air before heat exchange with the use-side heat exchanger 102A. The humidity sensor 134A is disposed, for example, in the air path between the suction port (not shown) of the indoor unit 100A and the use side heat exchanger 102A. The input device 136A inputs an instruction to the air conditioner 1, and is a sensor that receives a signal from a remote controller, for example, not shown. For example, the user uses a remote controller (not shown) to give instructions for starting and stopping the air conditioning operation, instructions for switching the operation mode, instructions for changing the set temperature, instructions for adjusting the air flow, and the like. Can do.

The indoor unit fan 140A blows air to the use side heat exchanger 102A, and is installed in the vicinity of the use side heat exchanger 102A, for example. When the indoor unit fan 140A operates, indoor air is sucked from the suction port (not shown) of the indoor unit 100A, and the sucked air passes through the use-side heat exchanger 102A and is heat-exchanged, thereby using-side heat exchange. The conditioned air heat-exchanged in the vessel 102A is blown out into the room from the air outlet 106A. The indoor unit control device 150A controls the indoor unit 100A, and includes, for example, an analog circuit, a digital circuit, a CPU, or a combination of two or more thereof.

As shown in FIG. 2, the indoor unit control device 150A includes, for example, an acquisition unit 152A, a storage unit 154A, an indoor unit communication unit 156A, and an indoor unit control unit 158A. The acquisition unit 152A acquires, for example, a detection result of the heat exchange temperature sensor 130A, a detection result of the room temperature sensor 132A, a detection result of the humidity sensor 134A, an instruction from the user input to the input device 136A, and the like. The data acquired by the acquisition unit 152A is input to the indoor unit control unit 158A. The storage unit 154A includes, for example, a non-volatile memory and stores a control program executed by the indoor unit control unit 158A, a threshold value used for controlling the indoor unit 100A, and the like. Further, for example, the storage unit 154A is used as a work area when the indoor unit control unit 158A executes processing. The indoor unit control unit 158A uses the data acquired by the acquisition unit 152A, for example, to control the opening / closing state of the expansion device 104A, to control the opening / closing state of the louver 107A, and to control the rotation speed of the indoor unit fan 140A. . In addition, the indoor unit control unit 158A can communicate with the outdoor unit 200 via the indoor unit communication unit 156A.

As shown in FIGS. 1 and 2, the indoor unit 100B has substantially the same configuration as the indoor unit 100A. That is, the use side heat exchanger 102B corresponds to the use side heat exchanger 102A, the expansion device 104B corresponds to the expansion device 104A, the louver 107B corresponds to the louver 107A, and the heat exchange temperature sensor 130B corresponds to the heat exchange temperature sensor 130A. The room temperature sensor 132B corresponds to the room temperature sensor 132A, the humidity sensor 134B corresponds to the humidity sensor 134A, the input device 136B corresponds to the input device 136A, the indoor unit fan 140B corresponds to the indoor unit fan 140A, The indoor unit control device 150B corresponds to the indoor unit control device 150A, the acquisition unit 152B corresponds to the acquisition unit 152A, the storage unit 154B corresponds to the storage unit 154A, and the indoor unit communication unit 156B corresponds to the indoor unit communication unit 156A. The indoor unit control unit 158B corresponds to the indoor unit control unit 158A. Hereinafter, in order to facilitate understanding of this embodiment, the description of the indoor unit 100B may be omitted or simplified. In the following description, the constituent elements of the indoor unit 100A and the indoor unit 100B, and the indoor unit 100A and the indoor unit 100B may be described with the subscript A or B omitted.

[Cooling operation]
Next, an example of the operation during the cooling operation of the air conditioner 1 will be described. During the cooling operation, as shown in FIG. 1, the flow path switching device 204 of the outdoor unit 200 is switched to a solid line state. The refrigerant compressed by the compressor 202 of the outdoor unit 200 flows into the heat source side heat exchanger 206 via the flow path switching device 204. The refrigerant flowing through the heat source side heat exchanger 206 is condensed by exchanging heat with air. The refrigerant condensed in the heat source side heat exchanger 206 flows out of the outdoor unit 200 and flows into the indoor unit 100A and the indoor unit 100B.

The refrigerant flowing into the indoor unit 100A is decompressed by the expansion device 104A. The refrigerant decompressed by the expansion device 104A evaporates by exchanging heat with air in the use side heat exchanger 102A. The refrigerant evaporated in the use side heat exchanger 102A flows out from the indoor unit 100A and flows into the outdoor unit 200. The refrigerant that has flowed into the outdoor unit 200 is sucked into the compressor 202 via the flow path switching device 204 and compressed again.

The refrigerant flowing into the indoor unit 100B is decompressed by the expansion device 104B. The refrigerant decompressed by the expansion device 104B evaporates by exchanging heat with air in the use side heat exchanger 102B. The refrigerant evaporated in the use side heat exchanger 102B flows out from the indoor unit 100B and flows into the outdoor unit 200. The refrigerant that has flowed into the outdoor unit 200 is sucked into the compressor 202 via the flow path switching device 204 and compressed again.

[Heating operation]
Next, an example of the operation | movement at the time of the heating operation of the air conditioner 1 is demonstrated. During the heating operation, the flow path switching device 204 of the outdoor unit 200 illustrated in FIG. 1 is switched to a broken line state. The refrigerant compressed by the compressor 202 of the outdoor unit 200 flows out of the outdoor unit 200 via the flow path switching device 204 and flows into the indoor unit 100A and the indoor unit 100B.

The refrigerant flowing into the indoor unit 100A is condensed by exchanging heat with air in the use-side heat exchanger 102A. The refrigerant condensed in the use side heat exchanger 102A is decompressed by the expansion device 104A, flows out from the indoor unit 100A, and flows into the outdoor unit 200. The refrigerant flowing into the outdoor unit 200 flows into the heat source side heat exchanger 206, exchanges heat with air, and evaporates. The refrigerant evaporated in the heat source side heat exchanger 206 is sucked into the compressor 202 via the flow path switching device 204 and compressed again.

The refrigerant flowing into the indoor unit 100B is condensed by exchanging heat with air in the use-side heat exchanger 102B. The refrigerant condensed in the use side heat exchanger 102B is decompressed by the expansion device 104B, flows out from the indoor unit 100B, and flows into the outdoor unit 200. The refrigerant flowing into the outdoor unit 200 flows into the heat source side heat exchanger 206, exchanges heat with air, and evaporates. The refrigerant evaporated in the heat source side heat exchanger 206 is sucked into the compressor 202 via the flow path switching device 204 and compressed again.

[Condensation prevention operation]
FIG. 3 is a diagram illustrating an example of the operation of the dew condensation prevention operation of the air conditioner described in FIG. For example, first, in step S02 of FIG. 3, when the air conditioner 1 that has received an instruction from the user starts an air conditioning operation of a cooling operation or a heating operation, the indoor unit 100A and the indoor unit 100B illustrated in FIG. Air conditioning.

In step S04 in FIG. 3, when one or more indoor units 100 are in the operation suspension state, the process proceeds to step S06. In the operation stop state of the indoor unit 100, for example, the operation of the indoor unit fan 140 is stopped, the expansion device 104 is closed, and the louver 107 closes the outlet 106. Note that, for example, the indoor unit 100 enters an operation suspension state upon receiving a user instruction. Further, for example, the indoor unit 100 enters an operation stop state by a timer operation stop by a timer, an automatic operation stop when the area where the indoor unit 100 is installed reaches a target temperature, or the like. In the following, an example in which the indoor unit 100A is in the operation suspension state will be described.

In the indoor unit 100A in the operation stop state, condensation may occur as described below.
For example, when the air conditioner 1 is performing the cooling operation, the operation of the indoor unit fan 140A is stopped in the indoor unit 100A in the operation suspension state, so that the temperature around the use side heat exchanger 102A gradually increases. To drop. Further, when the louver 107A closes the outlet 106A, the temperature drop around the use side heat exchanger 102A is further increased. Even when the expansion device 104A is in a closed state, the expansion device 104A may not be fully closed due to dust biting or the like, and may be slightly opened. In this case, the user side heat exchanger 102A may be opened. Since the low-temperature refrigerant slightly flows, the temperature of the use side heat exchanger 102A gradually decreases. Note that the expansion device 104A may be slightly opened in order to suppress the possibility that the expansion device 104A is fixed to the valve. As a result, in the indoor unit 100A in the operation suspended state, the temperature inside the indoor unit 100A is significantly lower than the room temperature, and the indoor unit 100A in the operation suspended state is in a place with high humidity such as a bathroom or a kitchen. When it is installed in the vicinity, there is a risk that condensation will occur inside the indoor unit 100A or at the outlet 106A. When condensation occurs, there is a risk that the condensed water may drip into the room.
Further, for example, when the air conditioner 1 is performing the heating operation, the operation of the indoor unit fan 140A is stopped in the indoor unit 100A in the operation suspension state, and therefore the temperature around the use side heat exchanger 102A Gradually rises. Further, when the louver 107A closes the outlet 106A, the temperature rise around the use side heat exchanger 102A is further increased. Even when the expansion device 104A is in a closed state, the expansion device 104A may not be fully closed due to dust biting or the like, and may be slightly opened. In this case, the user side heat exchanger 102A may be opened. Since the high-temperature refrigerant flows slightly, the temperature of the use side heat exchanger 102A gradually increases. Note that the expansion device 104A may be slightly opened in order to suppress the possibility that the expansion device 104A is fixed to the valve. Further, the expansion device 104A may be slightly opened in order to suppress the accumulation of the refrigerant in the indoor unit 100A in the operation stop state. As a result, in the indoor unit 100A in the operation suspended state, the temperature inside the indoor unit 100A is significantly higher than the indoor temperature, and the indoor unit 100A in the operation suspended state is in a place with high humidity such as a bathroom or a kitchen. If it is installed in the vicinity, there is a risk of condensation occurring inside the indoor unit 100A. When condensation occurs, there is a risk that the condensed water may drip into the room.

Therefore, in the air conditioner 1 of the example of this embodiment, in step S06, the detection result of the heat exchange temperature sensor 130A, the detection result of the room temperature sensor 132A, and the humidity sensor 134A of the indoor unit 100A in the operation stop state. And whether or not there is a possibility of dew condensation.
For example, when the air conditioner 1 is performing the cooling operation, the dew point temperature is calculated from the detection result of the room temperature sensor 132A and the detection result of the humidity sensor 134A. Then, using the dew point temperature and the detection result of the heat exchanger temperature sensor 130A, it is estimated whether or not condensation may occur.
For example, when the air conditioner 1 is performing the heating operation, the dew point temperature is calculated from the detection result of the heat exchange temperature sensor 130A and the detection result of the humidity sensor 134A. Then, using the dew point temperature and the detection result of the room temperature sensor 132A, it is estimated whether or not condensation may occur.
Therefore, for example, the detection result of the room temperature sensor 132 and the detection result of the heat exchanger temperature sensor 130 are compared to determine a high temperature having a high temperature and a low temperature having a low temperature, and the detection by the humidity sensor 134. The dew point temperature is calculated from the result and the high temperature temperature, and the possibility of dew condensation is estimated using the dew point temperature and the low temperature temperature.

If it is estimated in step S06 that condensation may occur, the process proceeds to step S08. In step S08, the operation of indoor unit 100B during normal operation is stopped. For example, the operation of the compressor 202 of the outdoor unit 200 is stopped, the expansion device 104B of the indoor unit 100B is closed, the operation of the indoor unit fan 140B is stopped, and the louver 107B closes the outlet 106B.

In step S10, the flow path switching device 204 is switched, and in step S12, the condensation prevention operation is started. At the time of the dew condensation prevention operation, the expansion device 104A of the indoor unit 100A in the operation stop state is opened, the operation of the indoor unit fan 140A is kept stopped, and the louver 107A is kept closed. Then, the compressor 202 is operated. In the dew condensation prevention operation, since the flow path switching device 204 is switched, the detection result of the heat exchange temperature sensor 130 approaches the detection result of the room temperature sensor 132. By bringing the temperature inside the indoor unit 100A close to the room temperature, the risk of condensation is suppressed.

In step S14, when the difference between the detection result of the heat exchange temperature sensor 130A and the detection result of the room temperature sensor 132A is equal to or less than the threshold value, the process proceeds to step S16 and the condensation prevention operation is terminated. For example, the threshold value T1 when the air conditioner 1 is performing the cooling operation and the threshold value T2 when the air conditioner 1 is performing the heating operation are different values, but the same value. There may be.

In step S16, for example, the operation of the compressor 202 is stopped, the expansion device 104A of the indoor unit 100A in the operation suspension state is closed, the operation of the indoor unit fan 140A is stopped, and the louver 107A is moved to the outlet 106A. When the is kept closed, the condensation prevention operation is terminated.

In step S18, the flow path switching device 204 is switched, and in step S20, the operation of the indoor unit 100A that has been normally operated is restarted. That is, the expansion device 104B of the indoor unit 100B that has been normally operated is opened, the operation of the indoor unit fan 140B is started, the louver 107B opens the outlet 106A, and the compressor 202 is operated.

As described above, in the air conditioner 1 of this embodiment, the compressor 202, the flow path switching device 204, the heat source side heat exchanger 206, the expansion device 104, and the use side heat exchanger 102 are refrigerant pipes. An air conditioner 1 having a refrigerant circuit 1A that is connected and in which a refrigerant circulates, includes an indoor unit 100 that is installed indoors and accommodates a use side heat exchanger 102. The indoor unit 100 is a use side heat exchanger. The indoor unit fan 140 that blows air to the room 102, the room temperature sensor 132 that detects the temperature of the room, the heat exchanger temperature sensor 130 that detects the temperature of the use side heat exchanger 102, and the indoor unit 100 that is housed and used. A humidity sensor 134 that detects the humidity of the air before heat exchange with the side heat exchanger 102, and the indoor unit 100 is in the operation stop state of the indoor unit 100 in which the indoor unit fan 140 stops air blowing. At room temperature The detection result detected by 132, the detection result detected by the humidity sensor 134, and the detection result detected by the heat exchange temperature sensor 130 are used to estimate the possibility of condensation, and the possibility of condensation When there is, the flow switching device 204 is switched to execute a dew condensation prevention operation in which the detection result of the heat exchange temperature sensor 130 is brought close to the detection result of the room temperature sensor 132.
For example, the air conditioner 1 further includes a control device that controls the air conditioner 1, and the control device compares the detection result of the room temperature sensor 132 with the detection result of the heat exchanger temperature sensor 130. , A high temperature with a high temperature and a low temperature with a low temperature are determined, a dew point temperature is calculated from the detection result of the humidity sensor 134 and the high temperature temperature, and dew condensation occurs using the dew point temperature and the low temperature temperature Estimate the possibility, and perform condensation prevention operation when condensation may occur. The “control device” of the present invention corresponds to the indoor unit control device 150 or the outdoor unit control device 250.
Further, for example, when the difference between the detection result of the heat exchange temperature sensor 130 and the detection result of the room temperature sensor 132 becomes equal to or less than the threshold value, the dew condensation prevention operation is terminated and the flow path switching device 204 is switched.
In the air conditioner 1 of the example of this embodiment, since the temperature inside the indoor unit 100 is brought close to the room temperature, the condensation prevention operation that prevents the occurrence of condensation is performed. By performing, it is suppressed that the indoor environment changes. For example, in the condensation prevention operation, the temperature inside the indoor unit 100 is only brought close to the room temperature, so that the change in the room temperature during the condensation prevention operation is suppressed. In addition, power consumption is reduced as compared with the prior art that dries the interior of the indoor unit.
Moreover, in the air conditioner 1 of the example of this embodiment, since the operation of the indoor unit fan 140 is stopped at the time of the dew condensation prevention operation, compared with the conventional technology that prevents the condensation by performing the air blowing operation, The risk of discomfort is suppressed. Furthermore, in the air conditioner 1 of the example of this embodiment, since the blowing is stopped during the dew condensation prevention operation, the change in the indoor temperature during the dew condensation prevention operation is suppressed.

For example, the air conditioner 1 includes a plurality of indoor units 100 connected in parallel to each other, and is in a normal operation in which a cooling operation or a heating operation is performed without stopping the indoor unit 100 that is not in operation. When performing the dew condensation prevention operation when there is an indoor unit 100, the indoor unit 100 during normal operation stops the indoor unit fan 140. By stopping the indoor unit fan 140 of the indoor unit 100 during normal operation during the condensation prevention operation, it is possible to suppress the possibility that the indoor temperature changes.

For example, each of the plurality of indoor units 100 has the expansion device 104, and when performing the condensation prevention operation, the indoor unit 100 during normal operation reduces the opening degree of the expansion device 104. Further, for example, when the dew condensation prevention operation is executed, the indoor unit 100 during normal operation closes the expansion device 104. By reducing or closing the opening degree of the expansion device 104 of the indoor unit 100 during normal operation during dew condensation prevention operation, refrigerant having a temperature different from that during normal operation flows into the use-side heat exchanger 102. Can be suppressed. As a result, after the condensation prevention operation is completed, the indoor unit 100 that has been normally operated can quickly return to the state before the condensation prevention operation is executed.

Each of the plurality of indoor units 100 has a louver 107 that opens and closes the air outlet 106 that blows out the conditioned air, and the indoor unit 100 during normal operation closes the louver 107 when performing the dew condensation prevention operation. When the dew condensation prevention operation is executed, the change in the indoor temperature can be suppressed by closing the louver 107 of the indoor unit 100 during the normal operation.

The present invention is not limited to the above embodiment, and can be variously modified within the scope of the present invention. That is, the configuration of the above embodiment may be improved as appropriate, or at least a part of the configuration may be replaced with another configuration. Further, the configuration requirements that are not particularly limited with respect to the arrangement are not limited to the arrangement disclosed in the embodiment, and can be arranged at a position where the function can be achieved.

1 air conditioner, 1A refrigerant circuit, 100 indoor unit, 100A indoor unit, 100B indoor unit, 102 usage side heat exchanger, 102A usage side heat exchanger, 102B usage side heat exchanger, 104 expansion device, 104A expansion device, 104B expansion device, 106 outlet, 106A outlet, 106B outlet, 107 louver, 107A louver, 107B louver, 130 heat exchanger temperature sensor, 130A heat exchanger temperature sensor, 130B heat exchanger temperature sensor, 132 room temperature sensor, 132A room temperature sensor , 132B room temperature sensor, 134 humidity sensor, 134A humidity sensor, 134B humidity sensor, 136A input device, 136B input device, 140 indoor unit fan, 140A indoor unit fan, 140B indoor unit fan, 150 indoor unit control device 150A indoor unit controller, 150B indoor unit controller, 152A acquisition unit, 152B acquisition unit, 154A storage unit, 154B storage unit, 156A indoor unit communication unit, 156B indoor unit communication unit, 158A indoor unit control unit, 158B indoor unit control Part, 200 outdoor unit, 202 compressor, 204 flow path switching device, 206 heat source side heat exchanger, 208 heat source side heat exchanger fan, 250 outdoor unit control unit, 252 outdoor unit control unit, 254 outdoor unit communication unit.

Claims

An air conditioner having a refrigerant circuit in which a compressor, a flow path switching device, a heat source side heat exchanger, an expansion device, and a use side heat exchanger are connected by a refrigerant pipe and the refrigerant circulates,
An indoor unit installed indoors and containing the use side heat exchanger;
The indoor unit is
An indoor unit fan for blowing air to the use side heat exchanger;
A room temperature sensor for detecting the temperature in the room;
A heat exchanger temperature sensor for detecting the temperature of the use side heat exchanger;
A humidity sensor that is housed in the indoor unit and detects the humidity of the air before heat exchange with the user-side heat exchanger;
The indoor unit is stopped during operation of the indoor unit in which the indoor unit fan stops blowing air.
Using the detection result detected by the room temperature sensor, the detection result detected by the humidity sensor, and the detection result detected by the heat exchanger temperature sensor, the possibility of condensation is estimated, and condensation occurs. When there is a possibility
Switching the flow path switching device to bring the detection result of the heat exchanger temperature sensor closer to the detection result of the room temperature sensor, performing a dew condensation prevention operation,
Air conditioner.
A control device for controlling the air conditioner;
The control device compares the detection result of the room temperature sensor and the detection result of the heat exchanger temperature sensor to determine a high temperature temperature having a high temperature and a low temperature temperature having a low temperature,
Calculate the dew point temperature from the detection result of the humidity sensor and the high temperature temperature,
Using the dew point temperature and the low temperature temperature, the possibility of condensation is estimated, and when condensation is likely to occur, the condensation prevention operation is performed.
The air conditioner according to claim 1.
When the difference between the detection result of the heat exchange temperature sensor and the detection result of the room temperature sensor is equal to or less than a threshold value, the condensation prevention operation is terminated, and the flow path switching device is switched.
The air conditioner according to claim 1 or 2.
A plurality of indoor units connected in parallel to each other;
When there is the indoor unit during the operation stop and the indoor unit during the normal operation that is performing the cooling operation or heating operation without stopping the operation, when performing the dew condensation prevention operation,
The indoor unit during normal operation stops the indoor unit fan,
The air conditioner according to any one of claims 1 to 3.
Each of the plurality of indoor units has the expansion device,
When performing the anti-condensation operation,
The indoor unit during the normal operation reduces the opening of the expansion device,
The air conditioner according to claim 4.
When performing the anti-condensation operation,
The indoor unit during normal operation closes the expansion device;
The air conditioner according to claim 5.
Each of the plurality of indoor units has a louver that opens and closes an outlet for blowing out conditioned air,
When performing the anti-condensation operation,
The indoor unit during normal operation closes the louver,
The air conditioner according to any one of claims 4 to 6.