TW201912264A - Air conditioning machine - Google Patents

Abstract

An air conditioning machine (100) is provided with: a refrigerant circuit (Q) wherein a refrigerant is circulated in a refrigeration cycle sequentially through a compressor (31), a condenser, an outdoor expansion valve (34), and an evaporator; and a control unit that controls at least the compressor (31) and the outdoor expansion valve (34). Either the compressor or the evaporator is an outdoor heat exchanger (32), and the other is an indoor heat exchanger (12). The control unit causes the indoor heat exchanger (12) to function as an evaporator, and ends freezing treatment for freezing or bedewing the indoor heat exchanger (12) when a first period (for instance, a first freezing time) elapses after starting the freezing treatment.

Description

Air conditioner

[0001] The present invention relates to an air conditioner.

[0002] As a technique for forming an indoor heat exchanger of an air conditioner in a clean state, for example, Patent Document 1 describes an air conditioner that is provided with water after the operation of the greenhouse. The moisture attached to the surface of the heat sink is attached to the mechanism. Further, the moisture attachment mechanism causes the water to adhere to the surface of the heat sink of the indoor heat exchanger by operating the cold room after the operation of the greenhouse. [Prior Art Document] [Patent Document] [0003] [Patent Document 1] Japanese Patent No. 4931566

[Problem to be Solved by the Invention] However, in the technique described in Patent Document 1, the amount of water attached to the indoor heat exchanger is cleaned in order to clean the indoor heat exchanger even after the operation of the greenhouse. There are still deficiencies. The present invention has been made to solve the above problems, and an object of the invention is to provide an air conditioner capable of appropriately cleaning an indoor heat exchanger. [Means for Solving the Problem] [0006] In order to achieve the above object, an air conditioner according to the present invention includes a refrigerant circuit that sequentially passes a refrigerant, a condenser, and a first expansion from a refrigerant in a refrigeration cycle. a valve and an evaporator for circulating; and a control unit that controls at least the compressor and the first expansion valve; one of the condenser and the evaporator is an outdoor heat exchanger, and the other is an indoor heat exchanger; and the control unit makes the indoor The heat exchanger functions as an evaporator, and after the first freezing period (for example, the first freezing time tc1) elapses after the freezing process of freezing or dew condensation of the indoor heat exchanger is started, the freezing process is terminated. Other aspects of the present invention will be described in the embodiments to be described later. [Effects of the Invention] According to the present invention, it is possible to provide an air conditioner that can appropriately clean an indoor heat exchanger.

[First Embodiment] [Configuration of Air Conditioner] Fig. 1 is a view showing an external configuration of an air conditioner 100 according to the first embodiment. FIG. 1 is a front view showing the indoor unit 10, the outdoor unit 30, and the remote controller 40 included in the air conditioner 100. The air conditioner 100 is a machine that circulates a refrigerant by a refrigeration cycle (heat pump cycle) to perform air conditioning. As shown in Fig. 1, the air conditioner 100 includes an indoor unit 10 installed indoors (in an air-conditioned space), an outdoor unit 30 installed outside the room, and a remote controller 40 operated by a user. [0010] The indoor unit 10 has a remote controller signal transmitting and receiving unit 11. The remote controller signal transmitting/receiving unit 11 transmits and receives a specific signal to and from the remote controller 40 by infrared communication or the like. For example, the remote controller signal transmitting/receiving unit 11 receives a signal such as an operation/stop command, a change in the set temperature, a change in the operation mode, and a setting of a timer from the remote controller 40. Further, the remote controller signal transmitting and receiving unit 11 transmits the detected value of the indoor temperature or the like to the remote controller 40. In addition, although not shown in FIG. 1, the indoor unit 10 and the outdoor unit 30 are connected via a refrigerant pipe, and are connected via a communication line. [Fig. 2] Fig. 2 is an explanatory view showing a vertical cross-sectional configuration of an indoor unit 10 of the air conditioner 100 according to the first embodiment. The indoor unit 10 includes an indoor heat exchanger 12, a water receiving tray 13, an indoor fan 14, a housing base 15, filters 16, 16 and a front panel in addition to the remote controller signal transmitting and receiving unit 11 (see Fig. 1). 17. The left and right wind direction plates 18 and the up and down wind direction plates 19. [0012] The indoor heat exchanger 12 is a heat exchanger that exchanges heat between the refrigerant flowing through the heat transfer tubes 12g and the indoor air. The water receiving tray 13 is placed on the lower side of the indoor heat exchanger 12 to receive water dripping from the indoor heat exchanger 12. Further, the water dropped to the water tray 13 is discharged to the outside via a drain pipe (not shown). The indoor fan 14 is, for example, a cylindrical cross-flow fan, and is driven by an indoor fan motor 14a (see FIG. 4). The casing base 15 is provided with a casing of a machine such as the indoor heat exchanger 12 or the indoor fan 14. [0013] The filters 16 and 16 are provided on the upper side of the indoor heat exchanger 12 and the front side of the indoor heat exchanger 12 to remove dust from the air introduced through the air intake port h1 or the like. The front panel 17 is a panel provided to cover the filter 16 on the front side, and the lower end is a shaft that can be rotated toward the front side. Further, the front panel 17 may be configured to be non-rotating. [0014] The left and right wind direction plates 18 are plate-like members that adjust the flow direction of the air blown into the room in the left-right direction. The left and right wind direction plates 18 are disposed on the downstream side of the indoor fan 14 and are rotated in the left-right direction by the left and right wind direction plate motors 21 (see FIG. 4). [0015] The vertical wind direction plate 19 is a plate-shaped member that adjusts the flow direction of the air blown out into the room in the vertical direction. The vertical wind direction plate 19 is disposed on the downstream side of the indoor fan 14, and is rotated in the vertical direction by the vertical wind direction plate motor 22 (see FIG. 4). As described above, the air taken in through the air intake port h1 exchanges heat with the refrigerant flowing through the heat transfer tube 12g, and the air that has undergone heat exchange is guided to the blowing air passage h2. The air that has passed through the air blowing path h2 is guided to the specific direction by the left and right wind direction plates 18 and the vertical wind direction plate 19, and is blown out into the room through the air blowing port h3. [0017] FIG. 3 is an explanatory view showing a refrigerant circuit Q of the air conditioner 100 according to the first embodiment. Further, the solid arrow in Fig. 3 indicates the flow of the refrigerant during the operation of the greenhouse. Further, the dotted arrow in Fig. 3 indicates the flow of the refrigerant during the operation of the cold room. As shown in FIG. 3, the outdoor unit 30 includes a compressor 31, an outdoor heat exchanger 32, an outdoor fan 33, an outdoor expansion valve 34 (first expansion valve), and a four-way valve 35. [0018] The compressor 31 is a machine that compresses a low-temperature low-pressure gas refrigerant by a compressor motor 31a and discharges it as a high-temperature high-pressure gas refrigerant. The outdoor heat exchanger 32 is a heat exchanger that exchanges heat between the refrigerant passing through the heat transfer tubes (not shown) and the outside air fed from the outdoor fan 33. [0019] The outdoor fan 33 is provided in the vicinity of the outdoor heat exchanger 32 by a fan that sends outside air to the outdoor heat exchanger 32 by the driving of the outdoor fan motor 33a. The outdoor expansion valve 34 has a function of decompressing the refrigerant condensed by the "condenser" (one of the outdoor heat exchanger 32 and the indoor heat exchanger 12). Further, the refrigerant that has been depressurized by the outdoor expansion valve 34 is guided to the "evaporator" (the other of the outdoor heat exchanger 32 and the indoor heat exchanger 12). [0020] The four-way valve 35 is a valve that switches the flow path of the refrigerant in accordance with the operation mode of the air conditioner 100. That is, when the refrigerant operates in the cold room in the direction of the dotted arrow, the compressor 31, the outdoor heat exchanger 32 (condenser), the outdoor expansion valve 34, and the indoor heat exchanger 12 (evaporator) are looped via the four-way valve 35. In the refrigerant circuit Q in which the cells are sequentially connected, the refrigerant is circulated in a refrigeration cycle. [0021] When the refrigerant is operated in the greenhouse in the direction of the solid arrow, the compressor 31, the indoor heat exchanger 12 (condenser), the outdoor expansion valve 34, and the outdoor heat exchanger 32 (evaporator) are connected via a cross. In the refrigerant circuit Q in which the valves 35 are connected in a ring-like manner, the refrigerant is circulated in a refrigeration cycle. [0022] Specifically, the "condenser" and the "evaporation" are sequentially performed in the refrigerant circuit Q in which the refrigerant is circulated through the refrigeration cycle via the compressor 31, the "condenser", the outdoor expansion valve 34, and the "evaporator". One of the devices is the outdoor heat exchanger 32, and the other is the indoor heat exchanger 12. 4 is a block diagram showing a control function of the air conditioner 100 according to the first embodiment. The indoor unit 10 shown in FIG. 4 includes an imaging unit 23, an environment detecting unit 24, and an indoor control circuit 25 in addition to the above configuration. The imaging unit 23 is an imaging element such as a CCD sensor (Charge Coupled Device) or a CMOS sensor (Complementary Metal Oxide Semiconductor). Based on the imaging result of the imaging unit 23, the indoor control circuit 25 detects a person (in the room) who is present indoors. Further, the "person detecting unit" for detecting the person present in the air-conditioned space includes the imaging unit 23 and the indoor control circuit 25. [0024] The environment detecting unit 24 has a function of detecting the state of the room and the state of the device of the indoor unit 10, and includes an indoor temperature sensor 24a, a humidity sensor 24b, and an indoor heat exchanger temperature sensor 24c. The indoor temperature sensor 24a is a sensor that detects the temperature of the room (the air-conditioned space). The indoor temperature sensor 24a is disposed on the suction side of the air more than the filters 16, 16 (see FIG. 2). Thereby, as will be described later, when the indoor heat exchanger 12 is frozen, the detection error accompanying the influence of the heat radiation can be suppressed. [0025] The humidity sensor 24b is a sensor that detects the humidity of the air in the room (air-conditioned space), and is installed at a specific position of the indoor unit 10. The indoor heat exchanger temperature sensor 24c is a sensor that detects the temperature of the indoor heat exchanger 12 (see FIG. 2) and is installed in the indoor heat exchanger 12. The detected values of the indoor temperature sensor 24a, the humidity sensor 24b, and the indoor heat exchanger temperature sensor 24c are output to the indoor control circuit 25. [0026] The indoor control circuit 25 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). ), and various electronic circuits such as interfaces. Further, it reads out the program stored in the ROM and expands it in the RAM, and the CPU executes various processes. [0027] As shown in FIG. 4, the indoor control circuit 25 includes a storage unit 25a and an indoor control unit 25b. The memory unit 25a stores, in addition to the specific program, the imaging result of the imaging unit 23, the detection result of the environment detecting unit 24, the data received via the signal transmitting/receiving unit 11 of the remote controller signal, and the like. The indoor control unit 25b performs specific control based on the data stored in the storage unit 25a. The processing performed by the indoor control unit 25b is as will be described later. [0028] In addition to the above configuration, the outdoor unit 30 includes an outdoor temperature sensor 36 and an outdoor control circuit 37. The outdoor temperature sensor 36 is a sensor that detects the temperature of the outdoor (outside air temperature) and is installed at a specific portion of the outdoor unit 30. Further, although not shown in FIG. 4, the outdoor unit 30 further includes various sensors for detecting the suction temperature, the discharge temperature, the discharge pressure, and the like of the compressor 31 (see FIG. 3). The detected values of the respective sensors including the outdoor temperature sensor 36 are output to the outdoor control circuit 37. [0029] The outdoor control circuit 37, which is not shown, includes an electronic circuit such as a CPU, a ROM, a RAM, and various interfaces, and is connected to the indoor control circuit 25 via a communication line. As shown in Fig. 4, the outdoor control circuit 37 has a storage unit 37a and an outdoor control unit 37b. In the memory unit 37a, in addition to the specific program, the detected values of the various sensors including the outdoor temperature sensor 36 are stored. The outdoor control unit 37b controls the compressor motor 31a (that is, the compressor 31), the outdoor fan motor 33a, the outdoor expansion valve 34, and the like based on the data stored in the storage unit 37a. Hereinafter, the indoor control circuit 25 and the outdoor control circuit 37 will be referred to as "control unit K". [0030] Next, a process for washing the indoor heat exchanger 12 (see FIG. 2) will be described. As described above, the upper side of the indoor heat exchanger 12 and the front side (the suction side of the air) are provided with a filter 16 for collecting dust and dust (see Fig. 2). However, since fine dust and dust may pass through the filter 16 and adhere to the indoor heat exchanger 12, it is desirable to periodically clean the indoor heat exchanger 12. In the present embodiment, the moisture contained in the air contained in the indoor unit 10 is frozen by the indoor heat exchanger 12, and then the ice of the indoor heat exchanger 12 is melted, and the indoor heat exchanger 12 is washed. . Such a series of processes is referred to as "washing treatment" of the indoor heat exchanger 12. [ Fig. 5] Fig. 5 is a flowchart showing a washing process executed by the control unit K of the air conditioner 100 according to the first embodiment. This flowchart will be described with reference to Figs. 3 and 4 as appropriate. In addition, it is assumed that the air conditioning operation (cold room operation, warm room operation, etc.) is performed until the "start" of the fifth drawing. [0032] Further, the start condition of the washing process of the indoor heat exchanger 12 is set to be "starting". The "starting condition of the washing process" is, for example, a condition in which the cumulative value of the execution time of the air-conditioning operation reaches a specific value from the end of the previous washing process (the surface of the indoor heat exchanger 12 has dirt adhesion). And the timing to be washed). Further, it is also possible to set a time zone for performing the cleaning process in accordance with the operation of the remote controller 40 by the user. [0033] In step S101, the control unit K stops the air-conditioning operation for a specific time (for example, several minutes). The specific time mentioned above is used to stabilize the time of the refrigeration cycle and is preset. For example, when the indoor warming operation is interrupted until the start of the "start", and the indoor heat exchanger 12 is frozen (S102), the control unit K controls the four-way valve 35 to flow the refrigerant so as to reverse the operation of the greenhouse. Here, assuming that the flow direction of the refrigerant is suddenly changed, there is an overload on the compressor 31, and the sound or the like that is emitted may cause an abnormal feeling to the user. Therefore, in the present embodiment, the air-conditioning operation is stopped for a predetermined period of time before the freezing of the indoor heat exchanger 12 (S102) (S101). In this case, the control unit K may perform the freezing of the indoor heat exchanger 12 after a certain period of time has elapsed after the air-conditioning operation is stopped. [0035] Further, in the case where the cold room operation is interrupted and the indoor heat exchanger 12 is frozen, the process of step S101 may be omitted. This is because the direction in which the refrigerant flows during the operation of the cold room (in the beginning) is the same as the direction in which the refrigerant flows in the freezing of the indoor heat exchanger 12 (S102). [0036] Next, in step S102, the control unit K freezes the indoor heat exchanger 12 (the control unit K performs the freezing process). In other words, the control unit K causes the indoor heat exchanger 12 to function as an evaporator, so that the moisture contained in the air contained in the indoor unit 10 is frosted on the surface of the indoor heat exchanger 12 and frozen. Further, the time of the freezing treatment and the like will be described later. [0037] In step S103, the control unit K thaws the indoor heat exchanger 12 (ice attached to the surface thereof). For example, the controller K functions to melt the ice on the surface of the indoor heat exchanger 12 by causing the indoor heat exchanger 12 to function as a condenser. Thereby, the dust and the eschar attached to the indoor heat exchanger 12 are washed away. Further, it may be naturally thawed, or the indoor fan 14 may be rotated to be defrosted by the wind. [0038] In step S104, the control unit K causes the indoor heat exchanger 12 to dry. For example, the control unit K drives the indoor fan 14 to dry the water on the surface of the indoor heat exchanger 12. Thereby, the indoor heat exchanger 12 can be formed in a clean state. After the processing of step S104 is performed, the control unit K terminates a series of processes (terminating). [0039] Next, the details of the steps of FIG. 5 are explained. Fig. 6 is a flowchart showing a process for freezing the indoor heat exchanger 12 (S102 in Fig. 5, freezing processing) (refer to Figs. 3 and 4 as appropriate). In step S11, the control unit K performs initial setting. The initial setting item includes the elapsed time of the variable (the first elapsed time et1, the second elapsed time et2, and the third elapsed time et3), and the constant freezing time (the first freezing time tc1, the second freezing time tc2, and the third freezing) Time tc3), the temperature of the constant freezing reference (freezing upper limit temperature Tu, freezing lower limit temperature Td). Specifically, it will be described with reference to FIGS. 7 and 8. Moreover, each elapsed time of the variable is initialized to zero. In addition, et is an abbreviation for elapsed time. [0040] FIG. 7 is an explanatory diagram showing an example of temporal changes in the temperature of the indoor heat exchanger 12. The horizontal axis of Fig. 7 is the elapsed time from the "start" of Fig. 6. The vertical axis of Fig. 7 is the temperature TE of the indoor heat exchanger 12 (detected value of the indoor heat exchanger temperature sensor 24c: see Fig. 4). Further, the temperature is less than 0 ° C, and includes the freezing reference temperature, which is the upper limit of the upper limit of the freezing, and the lower limit temperature Td, which is the lower limit of the lower limit of the freezing. [0041] The temperature TE of the indoor heat exchanger 12 is roughly classified into a case where the freezing is hardly advanced (curve C1) based on the relative humidity of the air in the indoor air (air-conditioned space) after the start of the freezing process, and the freezing is smooth. The case of advancement (curve C2) and the case of rapid freezing (curve C3). In this case, as in the case of the curve C1, the time of the freezing process in the step S102 is the first freezing time tc1, and the temperature TE from the indoor heat exchanger 12 is frozen as the curve C2 is smoothly advanced. When the freezing time from when the upper limit temperature Tu is equal to or less than the second freezing time tc2, and when the freezing is rapidly performed as in the curve C3, the freezing time from when the temperature TE of the indoor heat exchanger 12 becomes equal to or lower than the freezing lower limit temperature Td The third freezing time tc3 is set. [0042] The relationship between the freezing times is tc1>tc2>tc3. In other words, as in the case of the curve C1, when the temperature TE of the indoor heat exchanger 12 falls below 0 ° C and slowly freezes, the first freezing time tc1 is set to be long; and as in the curve C3, the freezing is rapidly performed. At the time of advancement, the third freezing time tc3 is set to be short. For example, the first freezing time tc1 is 20 minutes, the second freezing time tc2 is 10 minutes, and the third freezing time tc3 is 5 minutes. In addition, in order to reliably terminate the washing process of FIG. 5, the first freezing time tc1 may be set to be not very long. [0043] As the variable corresponding to each freezing time, the elapsed time from the start time of the freezing process in step S102 is the first elapsed time et1, and when the temperature TE of the indoor heat exchanger 12 becomes the freezing upper limit temperature Tu or less The elapsed time is the second elapsed time et2, and the freezing time from when the temperature TE of the indoor heat exchanger 12 becomes equal to or lower than the freezing lower limit temperature Td is the third elapsed time et3. As shown in FIG. 7, as the "elapsed time" from the start of the specific control for freezing the indoor heat exchanger 12 is lengthened, the temperature of the indoor heat exchanger 12 gradually becomes lower. In the case of the curve C1, the freezing process (in this example, 20 minutes) is terminated when the first elapsed time et1 reaches the first freezing time tc1. In the case of the curve C2, the freezing process is terminated when the second elapsed time et2 reaches the second freezing time tc2. In the case of the curve C3, the freezing process is terminated when the third elapsed time et3 reaches the third freezing time tc3. Thereby, a sufficient amount of water necessary for washing the indoor heat exchanger 12 can be frozen by the indoor heat exchanger 12 at the time of reaching each freezing time. [0045] FIG. 8 is a diagram showing the relationship between the relative humidity of indoor air and the freezing time. The horizontal axis of Fig. 8 is the relative humidity of the indoor air, and is detected by the humidity sensor 24b (refer to Fig. 4). The vertical axis of Fig. 8 is the freezing time set corresponding to the relative humidity of the indoor air. The first freezing time tc1, the second freezing time tc2, and the third freezing time tc3 shown in Fig. 7 may be relatively changed in accordance with the freezing time in Fig. 8. As shown in FIG. 8, the higher the relative humidity of the indoor air in the control unit K, the shorter the freezing time for freezing the indoor heat exchanger 12 (for example, the first freezing time tc1 can be shortened). ). This is because the higher the relative humidity of the indoor air, the greater the amount of moisture contained in the indoor air of a specific volume, and the moisture tends to adhere to the indoor heat exchanger 12. By setting the freezing time in this manner, an appropriate amount of moisture necessary for cleaning the indoor heat exchanger 12 can be adhered to the indoor heat exchanger 12 and further frozen. [0047] Further, instead of the drawing (data table) shown in FIG. 8, a specific mathematical expression may be used. Further, instead of the relative humidity of the indoor air, the control unit K sets the freezing time based on the absolute humidity of the indoor air. That is, the control unit K can shorten the freezing time when the absolute humidity of the indoor air is higher. [0048] Returning to FIG. 6, in step S12, the control unit K controls the four-way valve 35. In other words, the control unit K controls the four-way valve 35 such that the outdoor heat exchanger 32 functions as a condenser and the indoor heat exchanger 12 functions as an evaporator. Moreover, when the cold room operation is performed immediately before the "cleaning process" (the series of processes shown in FIG. 5), the control device maintains the state of the four-way valve 35 in step S12. [0049] Next, in step S18 of FIG. 6, the control unit K sets the turning speed of the compressor 31. Specifically, the control unit K sets the rotation speed of the compressor motor 31a based on the detected outdoor temperature sensor 36, that is, the outdoor temperature, to drive the compressor 31. [0050] FIG. 9 is a diagram showing the relationship between the outdoor temperature and the rotational speed of the compressor 31. When the indoor heat exchanger 12 is frozen, the control unit K is as shown in Fig. 9, and the higher the outdoor temperature is, the more the rotation speed of the compressor motor 31a is increased. This is because, in order to take heat from the indoor air in the indoor heat exchanger 12, the heat release of the outdoor heat exchanger 32 must be sufficiently performed. For example, when the outdoor temperature is high, the control unit K increases the temperature and pressure of the refrigerant discharged from the compressor 31 by increasing the rotational speed of the compressor motor 31a. Thereby, the heat exchange of the outdoor heat exchanger 32 is appropriately performed, and even the freezing of the indoor heat exchanger 12 is appropriately performed. Further, instead of the drawing (data sheet) shown in Fig. 9, a specific mathematical formula can also be used. Incidentally, in the general air-conditioning operation (cooling operation or warm room operation), the rotation speed of the compressor 31 is controlled based on the temperature of the refrigerant discharged from the compressor 31 or the like. On the other hand, when the indoor heat exchanger 12 is frozen, since the temperature of the refrigerant discharged from the compressor 31 tends to be lower than that during normal air-conditioning operation, the outdoor temperature is used as another variable. In step S19 of FIG. 6, the control unit K adjusts the opening degree of the outdoor expansion valve 34. Further, in step S19, it is desirable to reduce the opening degree of the outdoor expansion valve 34 when the cold room is normally operated. Thereby, the refrigerant which is a low temperature and a low pressure during the operation of the general cold room flows into the indoor heat exchanger 12 via the outdoor expansion valve 34. Therefore, the water adhering to the indoor heat exchanger 12 becomes easy to be frozen, and the amount of power consumption necessary for the freezing of the indoor heat exchanger 12 can be reduced. [0053] Next, in step S20, the control unit K performs a termination process of the freezing process. The termination processing of the freezing process is constituted by steps S21 to S28. Refer to Figure 7 as appropriate. [0054] In step S21, the control unit K adds Δt (control time interval) as a constant to the first elapsed time et1 in the timer measurement, and determines whether the first elapsed time et1 is the first freezing time in step S22. Tc1 or more (t1≧tc1). When the first elapsed time et1 is equal to or greater than the first freezing time tc1 (S22: YES), the freezing process is terminated. If the first elapsed time et1 has not reached the first freezing time tc1 (S22: NO), the process proceeds to step S23. [0055] In step S23, the control unit K determines whether or not the temperature TE of the indoor heat exchanger 12 in the sensor measurement is equal to or lower than the freezing upper limit temperature Tu (TE≦Tu). When the temperature TE of the indoor heat exchanger 12 is equal to or less than the freezing upper limit temperature Tu (S23: YES), the process proceeds to step S24, and if the temperature TE of the indoor heat exchanger 12 is not equal to or lower than the freezing upper limit temperature Tu (S23: NO), the process returns to Step S21. [0056] In step S24, the control unit K adds Δt (control time interval) as a constant to the second elapsed time et2 in the timer measurement, and determines whether the second elapsed time et2 is the second freezing time tc2 in step S25. Above (t2≧tc2). When the second elapsed time et2 is equal to or longer than the second freezing time tc2 (S25: YES), the freezing process is terminated. If the second elapsed time et2 has not reached the second freezing time tc2 (S25: NO), the process proceeds to step S26. [0057] In step S26, the control unit K determines whether or not the temperature TE of the indoor heat exchanger 12 in the sensor measurement is equal to or lower than the freezing lower limit temperature Td (TE≦Td). When the temperature TE of the indoor heat exchanger 12 is equal to or less than the freezing lower limit temperature Td (S26: YES), the process proceeds to step S27, and if the temperature TE of the indoor heat exchanger 12 is equal to or lower than the freezing lower limit temperature Td (S26: NO), the process returns to Step S21. [0058] In step S27, the control unit K adds a constant Δt (control time interval) to the third elapsed time et3 in the timer measurement, and determines in step S28 whether or not the third elapsed time et3 is the third freezing time tc3 or more. (t3≧tc3). When the third elapsed time et3 is equal to or longer than the third freezing time tc3 (S28: YES), the freezing process is terminated. If the third elapsed time et3 has not reached the third freezing time tc3 (S28: NO), the process returns to step S21. [0059] The processing of step S20 described above will be specifically described below with reference to FIG. 7. In the case of the curve C1, at the time t when the first elapsed time et1 reaches the first freezing time tc1 _G The freezing process of step S102 of Fig. 6 (Fig. 5) is terminated. Thereby, it is possible to proceed positively to the next step. Further, the first freezing time tc1 should be set to a time when the indoor heat exchanger 12 is frozen. [0060] In the case of curve C2, at time t _E (the second elapsed time et2 from the time when the temperature TE of the indoor heat exchanger 12 becomes the freezing determination condition, that is, the freezing upper limit temperature Tu), and the time t to reach the second freezing time tc2 _F The freezing process of step S102 of Fig. 6 (Fig. 5) is terminated. Thereby, in the case where the freezing is smoothly advanced, the first freezing time tc1 is not waited, and the next step can be surely advanced. [0061] In the case of curve C3, since time t _A The second elapsed time et2 is monitored until the temperature TE of the indoor heat exchanger 12 is equal to or lower than the freezing upper limit temperature Tu. On the other hand, the elapsed time from the time tc (the time when the temperature TE of the indoor heat exchanger 12 is equal to or lower than the freezing lower limit temperature Td) is the elapsed time from the third elapsed time et3 to the third freezing time tc3. _D The freezing process of step S102 of Fig. 6 (Fig. 5) is terminated. This is because, time t _D Not at time t _A The second elapsed time et2 reaches the time t of the second freezing time tc2 _B Caused. As a result, when the curve C3 is more rapidly advanced than the curve C1 and the curve C2, the first freezing time tc1 and the second freezing time tc2 are not waited for, and the second step can be surely advanced. Further, although not shown in FIG. 6, when the indoor heat exchanger 12 is frozen (that is, during a period until a specific freezing time elapses), the control unit K can set the indoor fan 14 to the stop state. Further, the indoor fan 14 can be driven at a specific turning speed. This is because, in either case, the freezing of the indoor heat exchanger 12 is promoted. In the case where the outdoor temperature is equal to or lower than the freezing point, the control unit K preferably does not perform the freezing of the indoor heat exchanger 12. This is because it is necessary to prevent the amount of water flowing down due to the thawing of the indoor heat exchanger 12 to be frozen in the drain pipe (not shown), and further prevent the drainage through the drain pipe from being hindered. [0064] FIG. 10 is an explanatory diagram of switching of ON/OFF of the compressor 31 and the indoor fan 14. The horizontal axis of Fig. 10 is the time. The vertical axis of Fig. 10 indicates ON/OFF of the compressor 31 and ON/OFF of the indoor fan 14. In the example shown in FIG. 10, the specific air-conditioning operation system such as the cold room and the warm room is driven to the time t1, and the compressor 31 and the indoor fan 14 are driven (that is, in the ON state). Then, at time t1 to t2, the compressor 31 and the indoor fan 14 are stopped (step S101 in Fig. 5). Then, at time t2 to t3, the freezing of the indoor heat exchanger 12 is performed (step S102 of Fig. 5). Further, as described above, when the air-conditioning operation is a cold room, the stop of the time t1 to t2 can be omitted. [0066] The time from the time t2 to t3 is the time determined by the freezing process in step S102 (refer to FIG. 6). Specifically, as shown in FIG. 7, in the case of the curve C1, the time from the time t2 to the time t3 is from the start of the freezing process to the time t. _G The time until then. In the case of the curve C2, the time from the time t2 to the time t3 is from the start of the freezing process to the time t _F The time until then. In the case of curve C3, the time from time t2 to t3 is from the beginning of the freezing process to the time t _D The time until then. [0067] In the example shown in FIG. 10, In the freezing of the indoor heat exchanger 12, The indoor fan 14 is stopped. With this, Because the cold wind does not blow out indoors, Can be used without the comfort of the user, The indoor heat exchanger 12 is frozen. also, The processing after time t3 is as follows. 11 is a flowchart showing a process for thawing the indoor heat exchanger 12 (S103 in FIG. 5) (refer to FIG. 3 as appropriate, Figure 4). The control unit K freezes the indoor heat exchanger 12 by the process of the above-described step S102 (refer to FIG. 6). Perform a series of processing as shown in Figure 11. [0069] In step S103a, The control unit K determines whether or not the indoor temperature (the temperature of the air-conditioned space) is equal to or greater than a specific value. This specific value is a threshold value for determining whether or not the indoor heat exchanger 12 functions as a condenser. Pre-set. [0070] In step S103a, When the indoor temperature is a certain value or more (S103a: Yes), next, The control unit K terminates the process (terminate) for thawing the indoor heat exchanger 12. As explained below, This is because, When the indoor heat exchanger 12 is thawed, Same as when the greenhouse is running, The four-way valve 35 is controlled, However, when the indoor temperature is a certain value or more, The heat load on the condensation side of the refrigeration cycle (here, the indoor heat exchanger 12) becomes too large, It is not possible to obtain a balance with the evaporation side (here, the outdoor heat exchanger 32). also, This is still because, In the case of high indoor temperatures, The ice of the indoor heat exchanger 12 is naturally dissolved by the passage of time. [0071] processing after step S103b, Different from time t3~t4 in Figure 10, It is the control method of the variation. In step S103b, The control unit K controls the four-way valve 35. Specifically, The control unit K functions to cause the indoor heat exchanger 12 to function as a condenser. The four-way valve 35 is controlled such that the outdoor heat exchanger 32 functions as an evaporator. that is, The control unit K controls the four-way valve 35 in the same manner as when the greenhouse is in operation. [0072] In step S103c, The control unit K closes the vertical wind direction plate 19 (see Fig. 2). With this, Even if the indoor fan 14 is driven later (S103d), It also prevents water droplets from flying out into the room with the air. [0073] In step S103d, The control unit K drives the indoor fan 14. With this, The air is taken in via the air intake port h1 (see Fig. 2). Further, the incorporated air leaks into the room through the gap between the vertical louver 19 and the front panel 17. therefore, It is possible to suppress the temperature of the indoor heat exchanger 12 (condenser) from becoming excessively high. [0074] In step S103e, The control unit K sets the rotation speed of the compressor 31 to a specific value. The compressor 31 is driven. In step S103f, The control unit K adjusts the opening degree of the outdoor expansion valve 34. In this way, by appropriately controlling the compressor 31 and the outdoor expansion valve 34, The high-temperature refrigerant flows through the indoor heat exchanger 12 as a condenser. The result is that The ice of the indoor heat exchanger 12 is melted in one breath, Therefore, dust and angling attached to the indoor heat exchanger 12 will be washed away. then, The water containing dust and water falls to the water tray 13 (refer to Figure 2). It is discharged to the outside via a drain pipe (not shown). [0075] In step S103g, The control unit K determines whether or not a specific time has elapsed since the "start" of Fig. 11. This specific time is the time required for the thawing of the indoor heat exchanger 12, Pre-set. In step S103g, In the case where the specific time has not elapsed since the beginning (S103g: no), The process of the control unit K returns to step S103f. on the other hand, When a certain time has elapsed since the beginning (S103g: Yes), The control unit K terminates a series of processes (termination) for thawing the indoor heat exchanger 12. [0076] Again, Instead of one of the series shown in Figure 11, As shown in the timing diagram of Figure 10 (time t3~t4), The compressor 31 and the indoor fan 14 can be maintained in a stopped state. This is because, Even if the indoor heat exchanger 12 is not functioning as a condenser, The ice of the indoor heat exchanger 12 is still caused by natural melting at room temperature. With this, The power consumption required for thawing of the indoor heat exchanger 12 can be reduced. and, It is possible to suppress water droplets from adhering to the inside of the vertical wind direction plate 19 (see FIG. 2). 12 is a flow chart showing a process for drying the indoor heat exchanger 12 (S104 of FIG. 5). The control unit K defrosts the indoor heat exchanger 12 by the processing of the above steps S103a to S103g (see FIG. 11). Perform a series of processing as shown in Figure 12. [0078] In step S104a, The control unit K maintains the four-way valve 35, Compressor 31, The driving state of the indoor fan 14 or the like. that is, The control unit K controls the four-way valve 35 in the same manner as the defrosting of the indoor heat exchanger 12, and the indoor heat exchanger 12 serves as a condenser. Further, the compressor 31 and the indoor fan 14 and the like are continuously driven. By doing the same control as when the greenhouse is running, The high temperature refrigerant flows in the indoor heat exchanger 12, Moreover, air is incorporated into the indoor unit 10. The result is that The water attached to the indoor heat exchanger 12 evaporates. [0079] Second, In step S104b, The control unit K determines whether or not a specific time has elapsed since the start of the process of step S104a. Without a specific time (S104b: no), The processing of the control unit K returns to step S104a. on the other hand, In the case of a specific time (S104b: Yes), The process of the control unit K proceeds to step S104c. [0080] In step S104c, The control unit K performs a blowing operation. Specifically, The control unit K stops the compressor 31, The indoor fan 14 is driven at a specific turning speed. With this, Since the interior of the indoor unit 10 is dry, It can exert antibacterial and anti-mildew effects. [0081] Again, In the processing of step S104a and step S104c, The up-and-down wind direction plate 19 (refer to FIG. 2) can be closed. Moreover, the up-and-down wind direction plate 19 can also be opened. Second, In step S104d, The control unit K determines whether or not a specific time has elapsed since the start of the process of step S104c. Without a specific time (S104d: no), The processing of the control unit K returns to step S104c. on the other hand, After a certain period of time (S104d: Yes), next, The control unit K terminates a series of processes (termination) for drying the indoor heat exchanger 12. [0083] Again, In the timing diagram shown in Figure 10, After the warmth room (S104a in Fig. 12) is performed at time t4 to t5 (after the operation of the flow of the same refrigerant as the greenhouse), Air supply is performed at time t5 to t6 (S104c of Fig. 12). By doing the warmth and air supply in sequence, The indoor heat exchanger 12 can be efficiently dried. <Effect> According to the first embodiment, The control unit K freezes the indoor heat exchanger 12 (S102 in Fig. 5), The ice of the indoor heat exchanger 12 is thawed (S103). With this, Compared to the general cold room operation, A large amount of moisture (ice) can be attached to the indoor heat exchanger 12. and, Thawed by the indoor heat exchanger 12, There is a large amount of water flowing on its surface. Therefore, dust and rays adhering to the indoor heat exchanger 12 can be washed away. [0085] Again, When the indoor heat exchanger 12 is frozen, The control unit K sets the freezing time based on, for example, the relative humidity of the indoor air (see S102b in Fig. 6 and Figure 8). With this, The proper amount of water required for washing the indoor heat exchanger 12, The indoor heat exchanger 12 is frozen. [0086] In addition, When the indoor heat exchanger 12 is frozen, The control unit K sets the rotation speed of the compressor motor 31a based on the outdoor temperature (refer to S102c in Fig. 6 Figure 9). With this, In the freezing of the indoor heat exchanger 12, The heat release at the outdoor heat exchanger 32 can be appropriately performed. [0087] Again, When the control unit K freezes the indoor heat exchanger 12, In response to the freezing state of the indoor heat exchanger 12, The freezing treatment is appropriately terminated. that is, The control unit K functions as an evaporator of the indoor heat exchanger 12, After the freezing process of freezing or dew condensation of the indoor heat exchanger 12 is started, If it is after the first period (for example, The first freezing time tc1), Then the freezing process is terminated. [0088] Again, The control unit K is below a specific temperature in the indoor heat exchanger 12 (for example, Freezing upper limit temperature Tu or freezing lower limit temperature Td), And the second period that is shorter than the first period (for example, The second freezing time tc2 or the third freezing time tc3), The freezing process can then be terminated. With this, It can be moved early to the next. also, The specific temperature is the upper limit temperature required for freezing (for example, Freezing upper limit temperature Tu), Or the lower temperature required for freezing (for example, Freeze lower limit temperature Td). [0089] ≪ Second Embodiment ≫ Second Embodiment, When the indoor heat exchanger 12 (see FIG. 2) is frozen, the indoor fan 14 is driven at a low speed. It is different from the first embodiment. also, Second embodiment, When the indoor heat exchanger 12 is frozen, The up-and-down wind direction plate 19 (refer to FIG. 2) is directed upward. Further, the left and right wind direction plates 18 (see FIG. 2) are oriented in the lateral direction. This point is different from the first embodiment. also, Other points (the composition of the air conditioner 100 shown in Figs. 1 to 4, The flowchart of Fig. 5 and the like are the same as those of the first embodiment. therefore, The description is directed to a portion different from the first embodiment. As for the duplicated part, the description is omitted. [0090] FIG. 13 is a view showing an air conditioner 100 according to a second embodiment; A flowchart for processing (corresponding to S102 in FIG. 5) for freezing the indoor heat exchanger 12 (refer to FIG. 3 as appropriate, Figure 4). also, For the same processing as in Figure 6, Give the same step number. [0091] It is explained for step S102A of FIG. In step S12, After setting the four-way valve 35, The process of the control unit K proceeds to step S13. In step S13, The control unit K drives the indoor fan 14 at a low speed. that is, When the control unit K freezes the indoor heat exchanger 12, The rotation speed of the indoor fan 14 that sends the indoor air to the indoor heat exchanger 12 is set to be lower than the rated rotation speed. With this, In the freezing of the indoor heat exchanger 12, The air volume of the cold air blown from the indoor unit 10 can be reduced, This will keep the user's comfort from being damaged. [0092] In step S15, The control unit K sets the vertical wind direction plate 19 to be horizontal upward. Specifically, The control unit K controls the vertical wind direction plate motor 22 so as to blow cold air upward from the indoor unit 10 (see FIG. 4). With this, It can prevent the freezing of the indoor heat exchanger 12, The cold air blown from the indoor unit 10 is directly blown to the user. [0093] In step S16, The control unit K sets the right and left wind direction plates 18 in the lateral direction. that is, The control unit K controls the left and right wind direction plate motors 21 in a state in which the right and left wind direction plates 18 are turned right or left from the indoor unit 10 (see FIG. 4). With this, It can prevent the freezing of the indoor heat exchanger 12, The cold air blown from the indoor unit 10 is directly blown to the user. [0094] After the processing of step S16 is performed, The process of the control unit K proceeds to step S18. also, In addition to step S19, In addition to the processing of S20, Thawing and drying of the indoor heat exchanger 12 (S103 in Fig. 5, S104) is the same as the first embodiment. Therefore, the description is omitted. <Effect> According to the second embodiment, When the indoor heat exchanger 12 is frozen, The control unit K drives the indoor fan 14 at a low speed (S13 in Fig. 13). With this, The amount of wind that is blown from the indoor unit 10 can be reduced. also, When the indoor heat exchanger 12 is frozen, The control unit K has the up-and-down wind direction plate 19 facing upward (S15). The left and right wind direction plates 18 are oriented in the lateral direction (S16). With this, The cold air blown from the indoor unit 10 can be prevented from being directly blown to the user. The comfort for the user can be prevented from being damaged. [0096] Third Embodiment ≫ The third embodiment is different from the first embodiment in that The indoor heat exchanger 12A (see FIG. 14) has a first indoor heat exchanger 12a and a second indoor heat exchanger 12b. The first indoor heat exchanger 12a and the second indoor heat exchanger 12b are connected via an indoor expansion valve V (see FIG. 14). [0097] Again, In the third embodiment, one part of the indoor heat exchanger 12A is frozen by performing a so-called reheat dehumidification operation. This point is different from the first embodiment. also, As for the other points (Figure 1, The composition shown in Figure 4, The flowchart of Fig. 5 and the like are the same as those of the first embodiment. therefore, A description will be given of a portion different from the first embodiment. As for the duplicated part, the description is omitted. [ Fig. 14] Fig. 14 is an explanatory view showing a refrigerant circuit QA of the air conditioner 100A according to the third embodiment. As shown in Figure 14, The indoor unit 10A has: Indoor heat exchanger 12A, Indoor expansion valve V (second expansion valve), indoor fan 14, etc. also, The indoor heat exchanger 12A includes a first indoor heat exchanger 12a and a second indoor heat exchanger 12b. in this way, The first indoor heat exchanger 12a and the second indoor heat exchanger 12b are connected to each other via the indoor expansion valve V. The indoor heat exchanger 12A is constructed. also, In the example shown in Figure 14, The second indoor heat exchanger 12b is located above the first indoor heat exchanger 12a. [0099] performing general air conditioning operation (cold room operation, When the greenhouse is running, etc.) The indoor expansion valve V is controlled to be fully open. Moreover, the opening degree of the outdoor expansion valve 34 is appropriately adjusted. on the other hand, When performing the so-called reheat dehumidification operation, The outdoor expansion valve 34 is controlled to be fully open. The opening degree of the indoor expansion valve V is appropriately adjusted. also, The reheat dehumidification operation will be described later. [ Fig. 15] Fig. 15 is a flowchart showing a process for freezing the second indoor heat exchanger 12b (corresponding to S102 of Fig. 5) (refer to Fig. 14 as appropriate). In step S102B of Fig. 15, After the four-way valve 35 is set in step S12, The process of the control unit K proceeds to step S17. [0101] In step S17, The control unit K performs a reheat dehumidification operation. Specifically, The control unit K functions to use the outdoor heat exchanger 32 and the first indoor heat exchanger 12a as condensers. The square valve 35 is controlled such that the second indoor heat exchanger 12b functions as an evaporator. In other words, The control unit K functions as an evaporator in one of the first indoor heat exchangers 12a and the second indoor heat exchangers 12b on the downstream side of the indoor expansion valve V (the second indoor heat exchanger 12b). [0102] Further, The control unit K sets the outdoor expansion valve 34 to be fully open. The indoor expansion valve V is set to a specific opening degree. With this, The low temperature air exchanged by the second indoor heat exchanger 12b as the evaporator, The first indoor heat exchanger 12a, which is the other of the condensers, is moderately heated and dehumidified. [0103] After the process of step S17 is performed, In step S18, The control unit K sets the rotation speed of the compressor 31, The compressor 31 is driven at its turning speed. In step S19x, The control unit K adjusts the opening degree of the indoor expansion valve V as appropriate. [0104] Second, The processing after step S20 is performed. In step S23 and step S25 in this process, The temperature TE of the indoor heat exchanger 12 is changed as the temperature of the second indoor heat exchanger 12b, and the determination process is performed. [0105] Again, Thawing the second indoor heat exchanger 12b, Further, the first indoor heat exchanger 12a and the second indoor heat exchanger 12b are dried. And the first embodiment (refer to FIG. 11 , Figure 12) The same, Therefore, the description thereof is omitted. Incidentally, When thawing and drying, The control unit K sets the indoor expansion valve V to be fully open. The opening degree of the outdoor expansion valve 34 is appropriately adjusted. [0106] As described above, Among the first indoor heat exchanger 12a and the second indoor heat exchanger 12b shown in Fig. 14, One (second indoor heat exchanger 12b) is located above the other (first indoor heat exchanger 12a). According to such a composition, When the frozen ice of the second indoor heat exchanger 12b is melted, Then, the water will flow to the first indoor heat exchanger 12a. With this, Both the first indoor heat exchanger 12a and the second indoor heat exchanger 12b can be cleaned. <Effect> According to the third embodiment, By performing a reheat dehumidification operation, The second indoor heat exchanger 12b can be frozen. also, Since the first indoor heat exchanger 12a is located above the second indoor heat exchanger 12b, Therefore, if the second indoor heat exchanger 12b is thawed, With its water, Both the first indoor heat exchanger 12a and the second indoor heat exchanger 12b can be cleaned. ≪Fourth Embodiment ≫ The fourth embodiment differs from the first embodiment in that When the indoor heat exchanger 12 (see Fig. 2) is frozen, The control unit K drives the indoor fan 14 and the outdoor fan 33 (see FIG. 4) at a low speed. and, The control unit K sets the opening degree of the outdoor expansion valve 34 to a specific value (fixed value). It is different from the first embodiment. also, Other points (such as the composition of the air conditioner 100 shown in Figures 1 to 4, The flowchart of Fig. 5 and the like are the same as those of the first embodiment. therefore, A description will be given of a portion different from the first embodiment. As for the duplicated part, the description is omitted. [Fig. 16] Fig. 16 is a view showing an air conditioner 100 according to a fourth embodiment. Flowchart for processing the indoor heat exchanger 12 (corresponding to S102 of FIG. 5) (refer to FIG. 3 as appropriate, Figure 4). also, The same processing as in the first embodiment (see FIG. 6) Give the same step number. [0110] In step S102C of FIG. 16, In step S12, After controlling the four-way valve 35, The process of the control unit K proceeds to step S13. In step S13, The control unit K drives the indoor fan 14 at a low speed. that is, When the control unit K freezes the indoor heat exchanger 12, The turning speed of the indoor fan 14 that sends the indoor air to the indoor heat exchanger 12 is set to be lower than the rated turning speed. With this, In the freezing of the indoor heat exchanger 12, The air volume of the cold air blown from the indoor unit 10 can be reduced, The user's comfort is not impaired. [0111] In step S14, The control unit K drives the outdoor fan 33 at a low speed. that is, The control unit K sets the rotation speed of the outdoor fan 33 that sends the outside air to the outdoor heat exchanger 32 to be lower than the rated rotation speed. With this, The heat exchange between the outside air and the refrigerant of the outdoor heat exchanger 32 can be obtained, A balance between heat exchange between the indoor air and the refrigerant of the indoor heat exchanger 12. also, Based on their respective rated swing speeds, It is desirable that the lower the rotational speed of the indoor fan 14 is, Then, the turning speed of the outdoor fan 33 is also set to be low. [0112] In step S18, The control unit K sets the rotation speed of the compressor 31. E.g, The control unit K is the same as the first embodiment. The rotation speed of the compressor 31 is set based on the detected value of the outdoor temperature sensor 36. [0113] Second, In step S19z, The control unit K sets the opening degree of the outdoor expansion valve 34 to a specific value (fixed value). This particular value is suitable for the opening of the indoor heat exchanger 12 to be frozen, Pre-set. then, In step S20, The control unit K performs a freeze termination process. also, The thawing and drying of the indoor heat exchanger 12 and the first embodiment (S103 of Fig. 5, S104) the same, Therefore, the description is omitted. <Effect> According to the fourth embodiment, When the indoor heat exchanger 12 is frozen, The control unit K drives the indoor fan 14 at a low speed (S13 in Fig. 16). The outdoor fan 33 is driven at a low speed (S14). With this, The freezing of the indoor heat exchanger 12 can be reduced, The amount of cold air blown from the indoor unit 10, Moreover, the heat exchange between the condensation side and the evaporation side of the refrigerant can be balanced. also, When the indoor heat exchanger 12 is frozen, The control unit K sets the opening degree of the outdoor expansion valve 34 to a specific value (fixed value). With this, The simplification of the processing of the control unit K can be achieved. [5th Embodiment] The fifth embodiment differs from the fifth embodiment of the first embodiment in that Before step S102, Relative humidity of indoor air (indoor humidity, When the humidity of the air-conditioned space is above a certain humidity, Perform general cold room operation or dehumidification operation. also, Other points (the composition of the air conditioner 100 shown in Figs. 1 to 4, The flowchart of Fig. 5 and the like are the same as those of the first embodiment. therefore, A description will be given of a portion different from the first embodiment. As for the duplicated part, the description is omitted. [Fig. 17] Fig. 17 is a flowchart showing a washing process performed by a control unit of the air conditioner of the fifth embodiment. In step S101, After stopping the general air conditioning operation, Step S30 is performed. Step S30 is a process of reducing the indoor humidity. in particular, In step S31, The control unit K determines whether the indoor humidity is equal to or higher than a specific humidity. When the indoor humidity is above a certain humidity (S30: Yes), Carry out general cold room operation or dehumidification operation, The process returns to step S31. If the indoor humidity does not reach the specified humidity (S30: no), Proceed to step S102. also, Regarding the thawing and drying of the indoor heat exchanger 12, And the first embodiment (S103 of FIG. 5, S104) the same, Therefore, the description thereof is omitted. [0117] In the case where the indoor humidity is high humidity, If the freezing process of step S102 is performed, There is a case where there is too much condensation and a large amount of water drops in the indoor space occurs. According to the fifth embodiment, Before freezing, The humidity in the indoor space is reduced, The freezing process of the step S102 can be carried out. [0118] ≪ Change Example ≫ Above, The air conditioner 100 and the like according to the present invention are described in various embodiments, However, the invention is not limited by these descriptions. Various changes are possible. E.g, In various embodiments, For the purpose of sequentially processing the freezing and thawing and drying of the indoor heat exchanger 12 (S102 to S104 in Fig. 5), But it is not limited to this. also, One or both of the thawing and drying of the indoor heat exchanger 12 may also be omitted. This is because, The same is true in this case. The indoor heat exchanger 12 is naturally thawed at room temperature. And the indoor heat exchanger 12 is washed by the water thereof. Another reason is that Due to the continuation of the stop state of each machine, And then the operation of the air conditioner, etc. This causes the indoor heat exchanger 12 to dry. [0119] Again, When the indoor heat exchanger 12 is frozen, Controlled by the compressor motor 31a (refer to Figure 4), The flow rate of the refrigerant flowing through the indoor heat exchanger 12 is smaller than that in the normal air conditioning operation. According to this, The refrigerant evaporates continuously in the middle of the flow path of the indoor heat exchanger 12, Therefore, its upstream side is frozen, The downstream side is in an unfrozen state. With this, One part (upstream side) of the indoor heat exchanger 12 can be frozen on one side, While suppressing the introduction of cold air into the room. also, The rotation speed of the compressor motor 31a is low, Therefore, the amount of power consumed by the air conditioner 100 can be reduced. [0120] Again, In the case of the above control, It is preferable that the upstream side of the indoor heat exchanger 12 is located on the upper side than the downstream side of the indoor heat exchanger 12. therefore, If the upstream side of the indoor heat exchanger 12 is thawed, Then, the water thereof will flow to the downstream side of the indoor heat exchanger 12. With this, Both the upstream side and the downstream side of the indoor heat exchanger 12 can be cleaned. [0121] Again, In various embodiments, The process of washing the indoor heat exchanger 12 by freezing or the like of the indoor heat exchanger 12 will be described. But it is not limited to this. E.g, The indoor heat exchanger 12 can also be cleaned by defoaming the indoor heat exchanger 12 without freezing it. In this case, Compared with the general cold room operation and dehumidification operation, The control unit K sets the evaporation temperature of the refrigerant to be low. The specific instructions are as follows. The control unit K is based on the detected value of the indoor temperature sensor 24a (the temperature of the indoor air) shown in Fig. 4, The detected value of the humidity sensor 24b (relative humidity of the indoor air), And calculate the dew point of the indoor air. and, The control unit K controls the opening degree of the outdoor expansion valve 34, and the like. The temperature of the indoor heat exchanger 12 is made below the above dew point, And the specific freezing temperature is higher. [0122] The above "freezing temperature", When the temperature of the indoor air is lowered, The moisture contained in the indoor air is at a temperature at which the indoor heat exchanger 12 starts to freeze. By causing the indoor heat exchanger 12 to condense as it is, The dew condensation water can wash the indoor heat exchanger 12. [0123] Again, The control content in the case where the indoor heat exchanger 12 is dew condensation, Except that the opening degree of the outdoor expansion valve 34 is different, The control content is the same as the case where the indoor heat exchanger 12 is frozen. therefore, For the matters described in the various embodiments, It is also applicable to the case where the indoor heat exchanger 12 is dew condensation. [0124] Furthermore, It is also possible to make the indoor heat exchanger 12 dew condensation, The indoor heat exchanger 12 is dried. that is, In the case where the indoor heat exchanger 12 is dew condensation, The control unit K functions as the condenser in the indoor heat exchanger 12, Or carry out air supply operation, Or by continuing the stop state of the machine containing the compressor 31, The indoor heat exchanger 12 is dried. [0125] Again, The control unit K can alternately perform the freezing of the indoor heat exchanger 12 and the condensation of the indoor heat exchanger 12 for a specific period of time. E.g, In the case where the cleaning process of the indoor heat exchanger 12 is performed every time a specific start condition is established, The control unit K alternately performs condensation of the indoor heat exchanger 12 and condensation of the indoor heat exchanger 12. [0126] In addition, "Specific starting conditions", Means, for example, the cumulative execution time of the air-conditioning operation from the end of the previous washing process. The cumulative time reaches a certain value for this condition. With this, Compared with the case where the indoor heat exchanger 12 is washed by repeated use of refrigeration, Can reduce the frequency of cold air blowing out into the room, It can improve the comfort for the user. [0127] Again, The control unit K can alternately perform the freezing of the indoor heat exchanger 12 and the operation of the cold room after the warm room operation for a predetermined period of time. Compared with the case where the indoor heat exchanger 12 is washed by repeated use of refrigeration, It can reduce the frequency of cold air blowing out into the room. [0128] In addition, The condensation of the indoor heat exchanger 12 and the operation of the cold room after the operation of the greenhouse can be alternately performed for a specific period of time. Compared with the case where the indoor heat exchanger 12 is washed by repeated use of refrigeration, It can reduce the frequency of cold air blowing out into the room. [0129] Again, In the second embodiment, When the indoor heat exchanger 12 is frozen, The control unit K sets the vertical wind direction plate 19 upward (S15 of Fig. 13), The process of setting the left and right wind direction plates 18 in the lateral direction (S16) will be described. But it is not limited to this. E.g, When the indoor heat exchanger 12 is frozen, The control unit K can set the vertical wind direction plate 19 to the closed state. With this, It can suppress the blowing of cold air to the room. [0130] Again, When the indoor heat exchanger 12 is frozen, The control unit K can set the left and right wind direction plates 18 to be open to the left and right sides (the left and right wind direction plates 18 on the right side are directed to the right side, The left and right wind direction plates 18 on the left side are oriented to the left side). With this, It can suppress users who blow cold air directly into the room. [0131] Again, The control unit K may be based on the imaging result of the air-conditioned space by the imaging unit 23 (see FIG. 4). The upper and lower wind direction plate motor 22 (see Fig. 4) and the left and right wind direction plate motor 21 are controlled (see Fig. 4). that is, When the indoor heat exchanger 12 is frozen (or dewed), When the control unit K detects a person based on the imaging result of the air-conditioned space, a way of blowing cold air to the direction in which the person does not exist, The angles of the up-and-down wind direction plate 19 and the left and right wind direction plates 18 are adjusted. With this, It can prevent people from blowing cold air directly into the room. [0132] Again, When the indoor heat exchanger 12 is frozen, The control unit K may be an indoor temperature sensor 24a such as a thermopile or a pyroelectric type infrared sensor (human detecting unit: Refer to Figure 4) to obtain an indoor thermal image. In this case, The control unit K is in such a manner that the cold air is not sent into the high temperature area of the room (the area where a person may exist). The angles of the up-and-down wind direction plate 19 and the left and right wind direction plates 18 are adjusted. [0133] Again, In the second embodiment, When the indoor heat exchanger 12 is frozen, The control unit K explains the process of continuously driving the indoor fan 14 at a low speed (S13 in Fig. 13). But it is not limited to this. E.g, When the indoor heat exchanger 12 is frozen (or dewed), When the temperature of the indoor heat exchanger 12 becomes a specific value or less, The control unit K drives the indoor fan 14 at a specific turning speed. With this, It can be suppressed that the temperature of the indoor heat exchanger 12 is higher than a specific value, For the indoors to blow cold air. Furthermore, After the temperature of the indoor heat exchanger 12 becomes a specific value or less, The thickness of the ice of the indoor heat exchanger 12 is then smoothly increased. [0134] Furthermore, When the indoor heat exchanger 12 is frozen (or dewed), The control unit K may be alternately repeated to drive/stop the indoor fan 14. With this, Compared with the case of continuously driving the indoor fan 14, It can reduce the frequency of blowing cold air indoors. [0135] In addition, In the fourth embodiment, When the indoor heat exchanger 12 is frozen, The control unit K sets the rotation speed of the compressor motor 31a and the opening degree of the outdoor expansion valve 34 to a specific value (S18 of Fig. 16 S19z), But it is not limited to this. E.g, When the indoor heat exchanger 12 is frozen (or dewed), The control unit K may be configured to maintain the outdoor expansion valve 34 at a specific opening degree. The rotation speed of the compressor motor 31a is adjusted such that the temperature of the indoor heat exchanger 12 approaches a specific target temperature. By controlling the swing speed of the compressor motor 31a as usual, The indoor heat exchanger 12 can be frozen. [0136] Again, When the indoor heat exchanger 12 is frozen, The load of the compressor 31 has a possibility of becoming large. therefore, Preferably, the suction pressure of the compressor 31 is Spit pressure, The way in which the temperature of the discharge falls within a certain range, The freezing time is adjusted by the control unit K, The rotational speed of the compressor 31 and the opening degree of the outdoor expansion valve 34. [0137] In addition, To ensure reliability, Also for the indoor heat exchanger 12, The discharge temperature of the compressor 31, The current value of the compressor motor 31a, the swing speed, and the like are set to a specific upper limit value. [0138] Furthermore, When the outside air temperature is below freezing point, In order to prevent the water generated by the thawing of the indoor heat exchanger 12 from being frozen inside the drain pipe (not shown), It is also possible to provide a small heater (not shown) in a specific part of the drain pipe. [0139] Again, When the indoor heat exchanger 12 is frozen (or dewed), Due to the effects of heat radiation, The detection error of the indoor temperature sensor 24a has an increased possibility. that is, Compared to the actual temperature of the indoor air, There is a possibility that the detected value of the indoor temperature sensor 24a is low. therefore, In the case where the indoor heat exchanger 12 is frozen (or dew condensation), Can be set to match any of the following The control unit K corrects the detected value of the indoor temperature sensor 24a. [0140] (a) the indoor fan 14 is stopped, Or drive at a lower speed than the rated swing speed. (b) The up-and-down wind direction plate 19 is closed. (c) The dedicated movable shutter (not shown) that opens or blocks the air passage on the downstream side of the indoor fan 14 is closed. (d) The temperature of the indoor heat exchanger 12 is equal to or less than a specific value. [0141] Again, An example of correction of the detected value of the indoor temperature sensor 24a, The distance between the indoor heat exchanger 12 and the indoor temperature sensor 24a (fixed value) may be exemplified, And the temperature of the indoor heat exchanger 12, The control unit K corrects the detected value of the indoor temperature sensor 24a. E.g, It can also be set that the lower the temperature of the indoor heat exchanger 12, Then, the control unit K corrects the detection value (the temperature detection value of the air in the air-conditioned space) of the indoor temperature sensor 24a shown in FIG. 4 to increase it. With this, The error of the indoor temperature displayed in the remote controller 40 (refer to Fig. 4) can be reduced. [0142] Again, It is also possible to increase the elapsed time from the start of freezing from the indoor heat exchanger 12, The control unit K corrects the detected value of the indoor temperature sensor 24a to increase it. [0143] Furthermore, It is also possible to set the freezing of the indoor heat exchanger 12, The control unit K does not use the detected value of the indoor temperature sensor 24a for the control of each machine (ie, The detected value of the indoor temperature sensor 24a is ignored. [0144] In addition, It is also possible to set the freezing of the indoor heat exchanger 12, The control unit K repeats the driving/stopping of the indoor fan 14 by a specific cycle (that is, Reincorporating air into the indoor unit 10), The detection error of the indoor temperature sensor 24a is reduced. [0145] Again, In the first embodiment, When the indoor heat exchanger 12 is thawed, When the "indoor temperature" is equal to or greater than a specific value (S103a in Fig. 11: Yes), The process in which the indoor heat exchanger 12 does not function as a condenser will be described. But it is not limited to this. E.g, It may also be set when the indoor heat exchanger 12 is thawed. When the "outdoor temperature" is a specific value or more, The indoor heat exchanger 12 is not made to function as a condenser. This is because, It is assumed that the greenhouse operation is performed in a state where the outdoor temperature is a certain value or more. Then, the refrigerant in the outdoor heat exchanger 32 functioning as an evaporator absorbs heat excessively. However, it is impossible to obtain the balance of heat exchange between the condensation side and the evaporation side of the refrigerant. In this case, The control unit K performs the air supply operation. Or by continuing the stop state of the machine containing the compressor 31, The indoor heat exchanger 12 is thawed. [0146] In the first embodiment, For functioning by using the indoor heat exchanger 12 as a condenser, The case where the indoor heat exchanger 12 is thawed will be described. But it is not limited to this. that is, It is also possible to set the control unit K to perform the air blowing operation. Or by continuing the stop state of the machine containing the compressor 31, The indoor heat exchanger 12 is thawed. [0147] Again, In the first embodiment, It is aimed at implementing the operation of the greenhouse and the supply of air by the sequence. The process of drying the indoor heat exchanger 12 will be described (see FIG. 10). But it is not limited to this. that is, It can also be set after the thawing of the indoor heat exchanger 12, The indoor heat exchanger 12 functions as a condenser, Or carry out the air supply operation, Or by continuing the stop state of the machine containing the compressor 31, The indoor heat exchanger 12 is dried. [0148] Again, A large amount of water drops on the water receiving tray 13 due to the thawing of the indoor heat exchanger 12. therefore, It is also possible to achieve an antibacterial effect by mixing an antibacterial agent in the water receiving tray 13. In addition, An ultraviolet irradiation mechanism (not shown) may be provided in the indoor unit 10, Antibacterial is performed by irradiating the docking tray 13 with ultraviolet rays. [0149] In addition, An ozone generating mechanism (not shown) may be provided in the indoor unit 10, The ozone generating mechanism performs antibacterial action on the water receiving tray 13 and the like. also, In order to make the water flow easily through the water receiving tray 13, And make the water tray 13 antibacterial, The water tray 13 can be covered with a metal such as copper. [0150] Again, It can also be used in cold room operation and dehumidification operation. Water is accumulated in the water receiving tray 13, The accumulated water is pumped by a pump (not shown). The indoor heat exchanger 12 is washed. [0151] In addition, In various embodiments, The configuration of each of the indoor unit 10 (see FIG. 3) and the outdoor unit 30 (see FIG. 3) will be described. But it is not limited to this. that is, It is also possible to set a plurality of indoor units connected in parallel. Moreover, a plurality of outdoor units connected in parallel can also be provided. [0152] Again, Each embodiment is described in detail in order to explain the present invention in an easy-to-understand manner. But it does not mean that you must have all the constituents described. Furthermore, For a part of the constitution of each embodiment, Additional components can be added, Cut or replace. also, The above-mentioned mechanism and structure are shown as being necessary for explanation. However, if you do not represent the product, you must show all the institutions and components.

[0153]

100, 100A‧‧ Air Conditioner

10, 10A‧‧‧ indoor unit

12, 12A‧‧‧ indoor heat exchanger (evaporator / condenser)

12a‧‧‧1st indoor heat exchanger

12b‧‧‧2nd indoor heat exchanger

14‧‧‧Indoor fan

Windshield around 18‧‧

19‧‧‧Up and down wind direction board

23‧‧‧Photography Department (personal inspection department)

30‧‧‧Outdoor machine

31‧‧‧Compressor

31a‧‧‧Compressor motor (motor of compressor)

32‧‧‧Outdoor heat exchanger (condenser/evaporator)

33‧‧‧Outdoor fan

34‧‧‧Outdoor expansion valve (1st expansion valve)

35‧‧‧ four-way valve

40‧‧‧Remote control

K‧‧‧Control Department

Q, QA‧‧‧ refrigerant circuit

Et1‧‧‧1st elapsed time

Et2‧‧‧2nd elapsed time

Et3‧‧‧3rd elapsed time

Tc1‧‧‧1st freezing time (1st period)

Tc2‧‧‧2nd freezing time (2nd period)

Tc3‧‧‧3rd freezing time (2nd period)

Tu‧‧‧ freezing ceiling temperature

Td‧‧‧ freezing minimum temperature

V‧‧‧Indoor expansion valve (2nd expansion valve)

1 is a view showing an external configuration of an air conditioner according to a first embodiment. Fig. 2 is an explanatory view showing a longitudinal sectional configuration of an indoor unit of the air conditioner of the first embodiment. Fig. 3 is an explanatory view showing a refrigerant circuit of the air conditioner of the first embodiment. Fig. 4 is a block diagram showing the control function of the air conditioner of the first embodiment. Fig. 5 is a flow chart showing the washing process executed by the control unit of the air conditioner of the first embodiment. Fig. 6 is a flow chart showing a process for freezing the indoor heat exchanger of the first embodiment. Fig. 7 is an explanatory view showing an example of temporal changes in the temperature of the indoor heat exchanger. Figure 8 is a graph showing the relationship between the relative humidity of indoor air and the freezing time. Figure 9 is a graph showing the relationship between the outdoor temperature and the rotational speed of the compressor. Fig. 10 is an explanatory view showing switching of ON/OFF of a compressor and an indoor fan. Figure 11 is a flow chart showing the process for thawing the indoor heat exchanger. Figure 12 is a flow chart showing the process for drying the indoor heat exchanger. Fig. 13 is a flow chart showing a process for freezing the indoor heat exchanger of the second embodiment. Fig. 14 is an explanatory view showing a refrigerant circuit of the air conditioner of the third embodiment. Fig. 15 is a flow chart showing a process for freezing the second indoor heat exchanger of the third embodiment. Fig. 16 is a flow chart showing a process for freezing the indoor heat exchanger of the fourth embodiment. Fig. 17 is a flow chart showing the washing process executed by the control unit of the air conditioner of the fifth embodiment.

Claims (7)

An air conditioner comprising: a refrigerant circuit that circulates through a compressor, a condenser, a first expansion valve, and an evaporator in sequence by a refrigerant in a refrigeration cycle; and a control unit that controls at least the compressor And the first expansion valve; wherein one of the condenser and the evaporator is an outdoor heat exchanger and the other is an indoor heat exchanger; and the control unit functions as the evaporator by the indoor heat exchanger; After the freezing process of freezing or dew condensation of the indoor heat exchanger is started, the freezing process is terminated as soon as the first period has elapsed. The air conditioner according to claim 1, wherein the control unit is at a temperature lower than a specific temperature and a second period shorter than the first period after the start of the freezing process, Then, the above freezing treatment is terminated. An air conditioner according to claim 2, wherein the specific temperature is an upper limit temperature necessary for freezing the indoor heat exchanger. An air conditioner according to claim 2, wherein the specific temperature is a lower limit temperature necessary for freezing the indoor heat exchanger. The air conditioner according to claim 1, wherein the control unit performs a general cold room before the freezing process is started before the start of the freezing process, and when the humidity of the air-conditioned space is equal to or higher than a specific humidity. Running or dehumidifying operation. The air conditioner according to claim 1, wherein the control unit causes the indoor heat exchanger to function as the evaporator to freeze or dew the indoor heat exchanger; and the control unit is in the indoor heat exchanger In the freezing or dew condensation, when the indoor heat exchanger is equal to or lower than a specific temperature and shorter than the first period of the first period, the freezing process is terminated and the second operation is performed. The air conditioner according to claim 1, wherein the indoor heat exchanger includes a first indoor heat exchanger and a second indoor heat exchanger; and the first indoor heat exchanger and the first through the second expansion valve The second indoor heat exchanger is connected to each other to constitute the indoor heat exchanger, and the control unit is a one of the first indoor heat exchanger and the second indoor heat exchanger located on a downstream side of the second expansion valve The above-described freezing treatment is performed by functioning as an evaporator.