TWI705222B - air conditioner - Google Patents

Abstract

The air conditioner (100) is equipped with a refrigeration cycle (RC) with a compressor (32) and an indoor heat exchanger (64), a drain pan (140) that temporarily stores water that has adhered to the indoor heat exchanger and dropped as drainage, and A drain pump (PO) that discharges the drain water stored in the drain pan to the outside, and a control device (20) that controls the operation of the refrigeration cycle and the drain pump. The control device executes the freezing operation in which the indoor heat exchanger functions as an evaporator and the surface temperature of the indoor heat exchanger is below freezing to meet the requirements of "driving time of the drain pump after the normal cooling operation is completed <freezing operation The drain pump is driven based on the relationship of the driving time of the subsequent drain pump.

Description

air conditioner

The present invention relates to an air conditioner.

The indoor unit of the air conditioner is provided with a drain pan that temporarily stores water that has adhered to the indoor heat exchanger and dropped. Hereinafter, the water stored in the drain pan is referred to as "drain". The drain is drained to the outside through the pipe, but if the drain is not performed well, it will remain in the drain pan. As a result, odor and mildew may be generated. Therefore, there is an air conditioner in which an indoor unit of the air conditioner includes a drain pump for forcibly discharging drain water to the outside (for example, refer to Patent Document 1).

On the other hand, the so-called "freeze washing operation" is performed in an air conditioner. "Freezing and washing operation" is the following operation: after making ice (including frost) adhere to the surface of the indoor heat exchanger, the ice is thawed (melted), and the resulting water drop is used to make the heat adhere to the room. The fine dust of the exchanger flows down. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Application Publication No. 2018-25355

[The problem to be solved by the invention]

However, in the conventional air conditioner, it is not considered to drive the drain pump in connection with the freezing and washing operation. Therefore, in the conventional air conditioner, when the freezing and washing operation is performed, it is unclear which drain pump drive control can be performed to reliably reduce the residual amount of drain.

The present invention was made in order to solve the aforementioned problems, and its main object is to provide an air conditioner that reduces the residual amount of drain when the freeze washing operation is performed. [Means to solve the problem]

In order to achieve the foregoing object, the present invention is an air conditioner, including: a refrigeration cycle, which has: a compressor that compresses a refrigerant, and an indoor heat exchanger; and a drain pan that drops water that adheres to the indoor heat exchanger Temporary storage as drainage; a drainage pump, which discharges the drainage stored in the drainage pan to the outside; and a control device, which controls the operation of the aforementioned refrigeration cycle and the aforementioned drainage pump; the aforementioned control device, which executes the indoor The heat exchanger functions as an evaporator and the surface temperature of the indoor heat exchanger is frozen at the freezing point to meet the requirements of "driving time of the drain pump after the end of the normal cooling operation <drain after the freezing operation Drive the aforementioned drain pump based on the relationship of the pump drive time". Other methods will be described later. [Invention Effect]

According to the present invention, it is possible to reduce the residual amount of drain water when the freeze washing operation is performed.

Hereinafter, an embodiment of the present invention (hereinafter referred to as "this embodiment") will be described in detail with reference to the drawings. In addition, each drawing is only shown schematically to the extent that the present invention can be fully understood. Therefore, the present invention is not limited to the illustrated example. In addition, in each figure, the same reference numerals are given to the common constituent elements and the same constituent elements, and repetitive descriptions of these are omitted.

＜Configuration of air conditioner＞ Next, referring to Fig. 1, the configuration of the air conditioner 100 of the present embodiment will be described. Fig. 1 is a system diagram of an air conditioner 100 according to this embodiment.

As shown in Fig. 1, the air conditioner 100 includes an outdoor unit 30, an indoor unit 60, and a control device 20 that controls these. The indoor unit 60 sets the operation mode (cooling room, heating room, dehumidification, ventilation, etc.), indoor air volume (swift wind, strong wind, weak wind, etc.), target indoor temperature, etc., based on the signal input from the remote controller 90.

(Configuration of control device) The control device 20 is equipped with CPU (Central Processing Unit), DSP (Digital Signal Processor), RAM (Random Access Memory), ROM (Read Only Memory), etc. as general computer hardware, and the control program executed by the CPU is stored in the ROM And various materials, etc. The control device 20 controls each part of the outdoor unit 30 and the indoor unit 60 based on the control program. Furthermore, the details will be described later.

(Configuration of outdoor unit) The outdoor unit 30 includes a compressor 32, a four-way valve 34, and an outdoor heat exchanger 36. The compressor 32 includes a motor 32 a, and has a function of compressing the refrigerant flowing in through the four-way valve 34. The pipe a1 is provided with a suction-side temperature sensor 41 that detects the temperature of the refrigerant sucked into the compressor 32 and a suction-side pressure sensor 45 that detects the pressure of the refrigerant sucked into the compressor 32. In addition, the pipe a2 is provided with a discharge-side temperature sensor 42 that detects the temperature of the refrigerant discharged from the compressor 32 and a discharge-side pressure sensor 46 that detects the pressure of the refrigerant discharged from the compressor 32. In addition, a compressor temperature sensor 43 that detects the temperature of the compressor 32 is installed on the compressor 32.

The four-way valve 34 has a function of switching the direction of the refrigerant supplied to the indoor unit 60 according to whether the indoor heat exchanger 64 of the indoor unit 60 functions as an evaporator or a condenser. When the indoor heat exchanger 64 functions as an evaporator, for example, during cooling operation, the four-way valve 34 is switched so as to connect the pipes a2 and a3 along a path of a solid line and to connect the pipes a1 and a6. In this case, the high-temperature and high-pressure refrigerant discharged from the compressor 32 is cooled by the outdoor heat exchanger 36. The cooled refrigerant is supplied to the indoor unit 60 through the pipe a5.

In addition, when the indoor heat exchanger 64 functions as a condenser, for example, during heating operation, the four-way valve 34 is switched so that the pipes a2 and a6 are connected along the path of the broken line and the pipes a1 and a3 are connected. In this case, the high-temperature and high-pressure refrigerant discharged from the compressor 32 is supplied to the indoor unit 60 through the pipes a2 and a6. The outdoor fan 48 includes a motor 48 a and blows air to the outdoor heat exchanger 36.

The outdoor heat exchanger 36 is a heat exchanger that performs heat exchange between the air sent from the outdoor fan 48 and the refrigerant, and is connected to the compressor 32 through a four-way valve 34. In addition, the outdoor unit 30 is equipped with an outdoor heat exchanger inlet temperature sensor 51 that detects the temperature of the air flowing into the outdoor heat exchanger 36, and an outdoor heat exchanger refrigerant that detects the temperature of the gas side refrigerant of the outdoor heat exchanger 36. A gas temperature sensor 53 and an outdoor heat exchanger refrigerant liquid temperature sensor 55 that detects the temperature of the liquid side refrigerant of the outdoor heat exchanger 36.

The power supply unit 54 receives a three-phase AC voltage from the commercial power supply 22. The power measuring unit 58 is connected to the power supply unit 54 to measure the power consumption of the air conditioner 100. The DC voltage output from the power supply unit 54 is supplied to the motor control unit 56. The motor control unit 56 includes an inverter (not shown), and supplies AC voltage to the motor 32 a of the compressor 32 and the motor 48 a of the outdoor fan 48. In addition, the motor control unit 56 controls the motors 32a and 48a without sensors, thereby detecting the rotation speeds of the motors 32a and 48a.

(Construction of indoor unit) The indoor unit 60 includes an indoor expansion valve 62, an indoor heat exchanger 64, an indoor fan 66, a motor control unit 67, and a remote control communication unit 68 that performs bidirectional communication with the remote control 90. The indoor fan 66 includes a motor 66 a and blows air to the indoor heat exchanger 64. The motor control unit 67 includes an inverter (not shown), and supplies AC voltage to the motor 66a. In addition, the motor control unit 67 controls the motor 66a in a sensorless manner, thereby detecting the rotation speed of the motor 66a.

The indoor expansion valve 62 is inserted between the pipes a5 and a7 and has a function of adjusting the flow rate of the refrigerant flowing through the pipes a5 and a7 and reducing the pressure of the refrigerant on the secondary side of the indoor expansion valve 62. The indoor heat exchanger 64 is a heat exchanger that performs heat exchange between the indoor air sent from the indoor fan 66 and the refrigerant, and is connected to the indoor expansion valve 62 through a pipe a7.

In addition, the indoor unit 60 includes an indoor heat exchanger inlet air temperature sensor 70, an indoor heat exchanger exhaust air temperature sensor 72, an indoor heat exchanger inlet humidity sensor 74, and an indoor heat exchanger refrigerant liquid temperature sensor. Refrigerator 25, and indoor heat exchanger refrigerant gas temperature sensor 26. Here, the indoor heat exchanger inlet air temperature sensor 70 detects the temperature of the air sucked in by the indoor fan 66. In addition, the indoor heat exchanger discharge air temperature sensor 72 detects the temperature of the air discharged from the indoor heat exchanger 64.

In addition, the indoor heat exchanger inlet humidity sensor 74 detects the humidity of the air sucked by the indoor fan 66. In addition, the indoor heat exchanger refrigerant liquid temperature sensor 25 and the indoor heat exchanger refrigerant gas temperature sensor 26 are provided at the connection location between the indoor heat exchanger 64 and the pipe a6, and detect the temperature of the refrigerant circulating in the location. In this way, the compressor 32, the four-way valve 34, the outdoor heat exchanger 36, the indoor expansion valve 62, the indoor heat exchanger 64, and the pipes a1 to a7 form a refrigeration cycle RC.

＜Constitution of indoor unit＞ Next, referring to Fig. 2, the structure of the indoor unit 60 will be described. FIG. 2 is a side sectional view of the indoor unit 60. In this embodiment, a case where the indoor unit 60 is a ceiling-mounted device will be described. The ceiling installation type refers to a configuration in which the ceiling 130 is buried and the lower surface is exposed to the air-conditioning room. However, the indoor unit 60 may be a wall-mounted type, a ceiling-buried type, a floor-mounted type, or the like.

As shown in FIG. 2, the indoor heat exchanger 64 is formed in a plate shape bent in a substantially V shape, and is provided in the center of the indoor unit 60. The indoor fan 66 has fins arranged in a substantially cylindrical shape, and is arranged in front of the indoor heat exchanger 64. Below the indoor heat exchanger 64 and the indoor fan 66, a drain pan 140 that receives the water that has condensed and dropped on the surfaces of these and temporarily stores it is arranged. Hereinafter, the water stored in the drain pan 140 is referred to as "drain". The indoor unit 60 is provided with a drain pump PO for forcibly discharging the drain water stored in the drain pan 140 to the outside. In the present embodiment, the description will be made as a structure that the volume of the drain pan 140 is the same as or slightly smaller than the hypothetical generation amount of drain generated in a short time in the freeze washing operation described later.

An inclined air filter 142 is provided behind the indoor heat exchanger 64. In addition, the lower surface of the indoor unit 60 is covered by a decorative plate 143. In addition, an air suction port 144 formed by cutting a slit into the decorative plate 143 is formed below the air filter 142. The indoor heat exchanger inlet air temperature sensor 70 is provided between the indoor heat exchanger 64 and the air filter 142.

An air blowing duct 146 is formed in front of the indoor fan 66. The left-right wind direction board 148 is provided in the middle of the air blowing duct 146, and controls the direction of airflow in the left-right direction (vertical direction with respect to the paper surface). The up-and-down wind direction plate 150 is provided at the exit portion of the air blowing channel 146, and rotates around the fulcrum 150a to control the direction of the airflow in the up and down direction. The left and right wind direction plates 148 and the up and down wind direction plates 150 are rotationally driven by the control device 20 (refer to FIG. 1). The up-and-down wind direction plate 150 shown by the solid line in FIG. 2 shows the position in the fully opened state.

When the air conditioner 100 is stopped, the up-and-down wind direction plate 150 rotates to the fully closed position 152 indicated by the one-dot chain line. In addition, when the washing operation described later is performed, the up-and-down wind direction plate 150 rotates to the position 156 indicated by the one-dot chain line, and then rotates to the washing operation position 154. In addition, the larger the opening degree of the up-and-down wind direction plate 150 is, the smaller the duct resistance of the air blowing duct 146 is. However, even when the vertical wind direction board 150 is closed at the fully closed position 152, a gap FS is formed between the vertical wind direction board 150 and the decorative board 143, and some air flows through the gap FS.

In addition, in the present embodiment, for example, when it is necessary to clean the interior of the indoor unit 60, a cleaning lamp (not shown) for indicating this is provided on the decorative panel 143. In addition, a suction panel (not shown) for selectively sucking air in the air-conditioned room is provided between the air suction port 144 and the air filter 142.

＜Operation during freezing and washing operation of air conditioner＞ The air conditioner 100 of this embodiment can perform a freezing washing operation. The "freeze washing operation" is the operation of thawing (melting) ice (including frost) on the surface of the indoor heat exchanger 64, and using the force of the resulting water drop to make the heat adhere to the room The fine dust of the exchanger 64 flows down. In the "freezing and washing operation", a larger amount of drainage than normal cooling operation is generated in a short time.

Next, the operation of the air conditioner 100 during the freezing and washing operation will be described with reference to FIGS. 3 and 4. 3 is a flowchart showing the operation of the air conditioner 100 during the cleaning operation. 4 is a flowchart showing the operation of the air conditioner 100 during the freezing and washing operation.

In the sequence of processing shown in FIG. 3, when the user operates the remote controller 90 to instruct the execution of the freezing and washing operation, and when it is time to automatically perform the freezing and washing operation, a freezing operation request is generated, and the request is passed in response to the situation. The control of the control device 20 is executed.

As shown in FIG. 3, the process of freezing and washing operation is started when a freezing operation request is generated. Then, the control device 20 determines whether the freezing operation can be performed (step S105). In step S105, when it is determined that the freezing operation cannot be performed (in the case of "NO"), the freezing washing operation is stopped (step S110). On the other hand, in step S105, when it is determined that the freezing operation can be performed (in the case of YES), the control device 20 drives the drain pump PO (step S115). In addition, since drainage is generated in the initial stage of the freezing operation, the drainage pump PO can be driven in the initial stage of the freezing operation.

Next, the control device 20 starts the freezing operation (step S120), and after that, if a desired time has passed (if sufficient ice adheres to the indoor heat exchanger 64), the freezing operation is stopped (step S125). Next, the control device 20 starts a thawing operation for letting the dust on the surface of the indoor heat exchanger 64 flow down (step S130), and then, if a desired time has elapsed, stops the drain pump PO (step S135), and starts a drying operation (step S135) S140). After that, when a desired time has passed, the control device 20 stops a series of processing (processing of the freezing and washing operation). In addition, the process of step S135 (the process of stopping the drain pump PO) is deleted according to operation, or it can be moved to after step S140 (process of the drying operation).

Fig. 4 shows an example of a case where the freezing and washing operation is performed by inserting during the normal cooling operation. In the example shown in FIG. 4, the processes of "operation stop (of normal cooling operation)" processing, "compressor protection" operation, "air supply" operation, and "freeze washing" operation are sequentially performed. In the "freeze washing" operation, each process of "freeze" operation, "thaw" operation, and "dry" operation is performed. In addition, during the "dry" operation, each process of "air supply" operation, "heating" operation, and "heat dissipation" operation is performed.

Here, the "compressor protection" operation is an operation operation of stopping the driving of the compressor 32 and protecting the compressor 32. By stopping the drive of the compressor 32, the lubricating oil floating in the internal space falls in the direction of the oil reservoir (not shown), and the lubricating oil does not flow out of the compressor 32. The “air blowing” operation is an operation of driving the indoor fan 66 to blow wind to the indoor heat exchanger 64. The “freezing” operation is an operation operation that lowers the temperature of the indoor heat exchanger 64 and makes ice adhere to the surface of the indoor heat exchanger 64. The “thawing” operation is an operation that raises the temperature of the indoor heat exchanger 64 to defrost (melt) the ice adhering to the indoor heat exchanger 64 and to cause dust on the surface of the indoor heat exchanger 64 to flow down. The “drying” operation is an operation for drying the surface of the indoor heat exchanger 64. The “heating” operation is an operation operation for raising the temperature of the indoor heat exchanger 64. The “heat dissipation” operation is an operation operation for releasing the heat of the indoor heat exchanger 64 to the surroundings.

In the example shown in FIG. 4, the following processing is performed. First, from the time t0 to the time t1, the "operation stop" process of the cooling operation is performed. In addition, the "compressor protection" operation is performed from time t1 to time t2. In addition, the "air blowing" operation is performed from time t2 to time t3. In addition, the "freezing" operation is performed from time t3 to time t5. In addition, the "thawing" operation is performed from time t5 to time t6. In addition, the "air blowing" operation is performed from time t6 to time t7. In addition, the "heating" operation is performed from time t7 to time t8. In addition, the "heat dissipation" operation is performed from time t8 to time t9. In addition, the "air blowing" operation is performed after time t9. In addition, the "freeze washing" operation is performed from time t3 to time t9. In addition, the "dry" operation is performed from time t6 to time t9.

In the "operation stop" from time t0 to time t1, the state is as follows. The indoor fan 66, the outdoor fan 48, and the compressor 32 operating during the cooling operation until time t0 stop driving. The up and down wind direction plate 150 descends (opens) downward at an arbitrary angle. The suction panel (not shown) opens at any angle. Turn on the cleaning lamp (not shown). The drain pump PO is driven. Hereinafter, regarding each operation action, the constituent elements of the state change will be described.

In the "compressor protection" operation from time t1 to time t2, the indoor fan 66 and the outdoor fan 48 are each driven at a desired rotation speed. The inclination of the upper and lower wind direction plates 150 is set to an upward angle dedicated to freezing. The drain pump PO is driven from time t1 to time t1a, and stops driving at time t1a. In addition, time t1a is the time between time t1 and time t2.

In the "air blowing" operation from time t2 to time t3, the indoor fan 66 continues to be driven. The rotation speed of the indoor fan 66 during the "air blowing" operation is faster than the rotation speed during the period from time t1 to time t2 (the period during the "compressor protection" operation) (the same applies hereinafter).

In the "freezing" operation from time t3 to time t5, the indoor fan 66 is driven to time t4, and the driving is stopped at time t4. The outdoor fan 48 is driven to time t5, and the driving is stopped at time t5. The compressor 32 is driven to time t5, and the drive is stopped at time t5. The rotation speed of the indoor fan 66 during the "freezing" operation is faster than the rotation speed during the period from time t1 to time t2 (the period during the "compressor protection" operation), and is higher than the rotation speed from time t2 to time t3 ( During the "air supply" operation, the rotation speed is slow. In addition, the rotation speed of the outdoor fan 48 during the "freezing" operation is faster than the rotation speed during the period from time t1 to time t3 (the period during the "compressor protection" operation and the "air blowing" operation).

In the "thawing" operation from time t5 to time t6, the indoor fan 66, the outdoor fan 48, and the compressor 32 stop driving.

In the "air blowing" operation from time t6 to time t7, the indoor fan 66 is driven, and the inclination of the up-and-down wind direction plate 150 is set to a downward angle dedicated to freezing.

In the "warm room" operation from time t7 to time t8, the indoor fan 66 continues to be driven, and the driving is stopped at time t8. The outdoor fan 48 is driven to time t8, and the driving is stopped at time t8. The rotation speed of the outdoor fan 48 during the "heating" operation is faster than the rotation speed during the period from time t1 to time t3 (the period during the "compressor protection" operation and the "blowing" operation), and is faster than the rotation speed from time t3 to time t3. During the period of t5 (the period during which "freezing" is in operation), the rotation speed is slow.

During the "heat dissipation" operation from time t8 to time t9, the indoor fan 66, the outdoor fan 48, and the compressor 32 stop driving. In the "air blowing" operation after time t9, the indoor fan 66 is driven.

＜Main features of air conditioners＞ The air conditioner 100 of this embodiment has the following characteristics.

(1) As shown in FIG. 4, the control device 20 executes a freezing operation in which the indoor heat exchanger 64 functions as an evaporator and the surface temperature of the indoor heat exchanger 64 is below freezing, so as to satisfy the "normal cooling operation end". The drain pump PO is driven in the relationship of the subsequent drive time of the drain pump<the drive time of the drain pump after the freezing operation".

In addition, in the example shown in FIG. 4, the "driving time of the drain pump after the normal cooling operation ends" is the time from time t1 to time t1a. In addition, the "driving time of the drain pump after freezing operation" is the time after time t5.

In the "freezing and washing operation", a larger amount of drainage than normal cooling operation is generated in a short time. The air conditioner 100 of this embodiment drives the drain pump PO so as to satisfy the aforementioned relationship, so that the drain can be discharged to the outside efficiently and reliably. Therefore, the air conditioner 100 of the present embodiment can reliably reduce the residual amount of drainage when the freeze washing operation is performed. The air conditioner 100 of this embodiment can prevent the drain from being discharged from the drain pan 140, and can suppress the generation of malodor and mildew caused by the drain remaining in the drain pan 140.

(2) The control device 20 executes the thawing operation after the freezing operation ends, and it is preferable to drive the drain pump PO for at least a part of the time during the thawing operation. Thereby, the air conditioner 100 of the present embodiment can reduce the residual amount of drain water when the freezing and washing operation is performed.

(3) The control device 20 executes the drying operation after the freezing operation ends, and it is preferable that the drain pump PO can be driven during at least a part of the time during the thawing operation and the drying operation. Thereby, the air conditioner 100 of the present embodiment can more effectively reduce the residual amount of drain water when the freezing washing operation is performed.

(4) It is preferable that the control device 20 drives the drain pump PO while driving the indoor fan 66 in the drying operation.

In the interior of the indoor unit 60, while the indoor fan 66 is being driven, water generated during the thawing of the ice attached to the indoor heat exchanger 64 drops to the drain pan 140, and the drain may stay in the drain pan 140. Therefore, the air conditioner 100 of the present embodiment drives the drain pump PO while driving the indoor fan 66 in the drying operation. Thereby, the air conditioner 100 of the present embodiment can effectively and reliably reduce the residual amount of drainage when the freezing washing operation is performed.

(5) It is preferable that the control device 20 continuously turns on the driver of the drain pump PO for at least a part of the freezing operation, the thawing operation, and the drying operation.

The drain pump PO generates a relatively loud sound when the drive is switched on/off. Therefore, the control device 20 of the air conditioner 100 of the present embodiment continues to turn on the drive of the drain pump PO for at least a part of the freezing operation, the thawing operation, and the drying operation. Thereby, the air conditioner 100 of this embodiment can reduce the generation of noise caused by the drain pump PO.

(6) The control device 20 preferably stops the drain pump PO after a predetermined time or more has passed after the normal cooling operation ends, and thereafter, stops the drain pump PO continuously until the freezing operation starts. Thereby, the air conditioner 100 of this embodiment can ensure the time to stop the drain pump PO. Therefore, the air conditioner 100 of the present embodiment can achieve a corresponding reduction in energy consumption, that is, energy saving.

(7) It is preferable that the control device 20 continues to drive the drain pump PO for a certain period of time after the end of the drying operation. In addition, in the example shown in FIG. 4, "after the end of the drying operation" indicates the time t9 or later. The air conditioner 100 of this embodiment can discharge substantially all of the drain water remaining in the drain pan 140 to the outside by continuing to drive the drain pump PO for a certain period of time after the completion of the drying operation. Therefore, the air conditioner 100 of the present embodiment can effectively and reliably reduce the residual amount of drain when the freezing and washing operation is performed.

As described above, according to the air conditioner 100 of the present embodiment, it is possible to reduce the residual amount of drain water when the freeze washing operation is performed.

In addition, the present invention is not limited to the aforementioned embodiment, and various changes and modifications can be made without departing from the gist of the present invention.

For example, the foregoing embodiment is explained in order to easily and clearly explain the gist of the present invention. Therefore, the present invention is not limited to an aspect that must include all the components described. In addition, the present invention can add another component to a certain component or replace a part of the component with another component. In addition, the present invention can also delete some of the constituent elements.

For example, in the foregoing embodiment, the indoor unit 60 is described as an embodiment in which the indoor unit 60 is a ceiling-mounted device. However, the present invention can be applied even if the indoor unit 60 is a wall-mounted, ceiling-embedded, or floor-mounted device.

For example, the operation of the air conditioner 100 may be modified in the manner of the first modification example shown in FIG. 5 and the second modification example shown in FIG. 6. FIG. 5 is a flowchart showing the operation of the first modification of the air conditioner 100. FIG. 6 is a flowchart showing the operation of the second modification of the air conditioner 100.

(First modification) The operation of the first modified example shown in FIG. 5 is an operation when a stop operation by the user is accepted during the freezing operation. The operation of the first modified example shown in FIG. 5 is different from the operation of the aforementioned embodiment shown in FIG. 4 in that the indoor fan 66 is stopped by receiving a stop operation.

As shown in FIG. 5, in the operation of the first modification example, the time from the end of the normal cooling operation to the start of the drive of the discharge pump PO (that is, the time from the time t1a when the drain pump PO is stopped to the time t3) ) Is T11. On the other hand, the time from acceptance of the stop operation until the start of driving of the drain pump PO (that is, the time from time tA to time tB) is T12. In addition, the time T12 is a value larger than the time T11 (that is, a value satisfying the relationship of "T12>T11"). That is, in the operation of the first modification example, the time from the stop operation in the case of receiving the stop operation by the user during the freezing operation to the start of the drive of the drain pump PO is longer than the end of the operation in the normal cooling operation. It takes a long time until the drive of the drain pump PO starts.

The operation of this first modification can ensure the time for the lubricating oil floating in the internal space of the compressor 32 to fall in the direction of the oil reservoir (not shown). Thereby, the operation of the first modification can suppress the lubricating oil floating in the internal space of the compressor 32 from flowing out to the outside of the compressor 32 to reduce the operating efficiency of the refrigeration cycle RC.

(Second modification) The operation of the second modification example shown in FIG. 6 is an operation in a case where the drain pan 140 has a size such that the drain water generated in a short time during the freeze washing operation can be stored without overflowing. The operation of the second modification example shown in FIG. 6 is different from the operation of the aforementioned embodiment shown in FIG. 4 in that the drain pump PO is stopped during at least a part of the drying operation.

The operation of this second modification can ensure the time to stop the drain pump PO. Therefore, the operation of the second modification example can achieve a corresponding reduction in energy consumption, that is, energy saving. In addition, in the operation of the second modification example, the generation of noise can be suppressed by the time when the drain pump PO is stopped.

20: control device 22: Commercial power supply 25: Indoor heat exchanger refrigerant liquid temperature sensor 26: Indoor heat exchanger refrigerant gas temperature sensor 30: outdoor unit 32: Compressor 32a, 48a, 66a: Motor 34: Four-way valve 36: outdoor heat exchanger 41: Suction side temperature sensor 42: Discharge side temperature sensor 43: Compressor temperature sensor 45: suction side pressure sensor 46: Discharge side pressure sensor 48: outdoor fan 51: outdoor heat exchanger inlet temperature sensor 53: Outdoor heat exchanger refrigerant gas temperature sensor 54: Power Supply Department 55: Outdoor heat exchanger refrigerant liquid temperature sensor 56, 67: Motor Control Department 58: Electricity Measurement Department 60: Indoor unit 62: Indoor expansion valve 64: Indoor heat exchanger 66: Indoor fan 68: Remote control communication department 70: Indoor heat exchanger inlet air temperature sensor 72: Indoor heat exchanger exhaust air temperature sensor 74: Indoor heat exchanger inlet humidity sensor 90: remote control 100: Air conditioner 130: ceiling 140: drain pan 142: Air filter 143: decorative board 144: Air suction port 146: Air blowing channel 148: Left and right wind direction board 150: Up and down wind direction board 150a: pivot 152: fully closed position 154: Cleaning operation position 156: Location a1, a2, a3, a5, a6, a7: piping FS: gap PO: Drain pump RC: refrigeration cycle

[Fig. 1] is a system diagram of the air conditioner according to the embodiment. [Fig. 2] is a side sectional view of the indoor unit of the air conditioner according to the embodiment. [Fig. 3] Fig. 3 is a flowchart showing the operation during the freezing and washing operation of the air conditioner according to the embodiment. [Fig. 4] Fig. 4 is a flowchart showing the operation during the freezing and washing operation of the air conditioner according to the embodiment. [Fig. 5] is a flowchart showing the operation of the first modification of the air conditioner. [Fig. 6] is a flowchart showing the operation of the second modification of the air conditioner.

Claims (8)

An air conditioner with: The refrigeration cycle has: a compressor that compresses the refrigerant and an indoor heat exchanger; Drain pan, which temporarily stores the falling water attached to the aforementioned indoor heat exchanger as drain; A drain pump, which discharges the drain water stored in the drain pan to the outside; and A control device, which controls the actions of the aforementioned refrigeration cycle and the aforementioned drain pump; The aforementioned control device is Perform freezing operation in which the indoor heat exchanger functions as an evaporator and the surface temperature of the indoor heat exchanger is below freezing, The drain pump is driven so as to satisfy the relationship of "driving time of the drain pump after the end of the normal cooling operation<driving time of the drain pump after the freezing operation". Such as the air conditioner of claim 1, in which, The aforementioned control device is After the aforementioned freezing operation is completed, the thawing operation is executed, The drain pump is driven for at least a part of the time during the thawing operation. Such as the air conditioner of claim 2, in which, The aforementioned control device is After the aforementioned freezing operation is completed, the drying operation is executed, The drain pump is driven during at least a part of the time during the thawing operation and the drying operation. Such as the air conditioner of claim 3, in which, With indoor fan; The control device drives the drain pump while the indoor fan is driven in the dry operation. Such as the air conditioner of claim 3, in which, The control device continuously turns on the drive of the drain pump during at least a part of the freezing operation, the thawing operation, and the drying operation. Such as the air conditioner of claim 1, in which, When the normal cooling operation ends, the control device stops the drain pump after a predetermined time or more has passed, and then continues to stop the drain pump until the freezing operation starts. Such as the air conditioner of claim 4, in which, The control device continues to drive the drain pump for a certain period of time or longer even after the drying operation ends. Such as the air conditioner of claim 1, in which, The time from the start of the stop operation in the case of receiving the stop operation by the user during the aforementioned freezing operation to the start of the driving of the aforementioned drain pump is longer than the time from the end of the aforementioned normal cooling operation to the end of the operation. The time before the start of driving of the drain pump is long.

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