air conditioner

Abstract

To provide an air conditioner that enables refrigerant leak detection even while the unit is in operation. [Solution] The control unit 34 acquires the temperature difference Td detected by the evaporator heat exchanger temperature sensor 37a and the condenser heat exchanger temperature sensor 37b, and is capable of executing a dehumidification detection mode in which the temperature difference Td=Td1 is acquired after a first predetermined time has elapsed during dehumidification mode operation, and a cold air detection mode in which the temperature difference Td=Td2 is acquired after a second predetermined time has elapsed during cold air mode operation. After executing either the dehumidification detection mode or the cold air detection mode, the other mode is executed immediately afterward, and if the difference between the temperature difference Td2 and the temperature difference Td1 is within a predetermined range, the operation is stopped and an error is reported.

Description

Technical Field

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

Background Art

[0002] For example, Patent Document 1 describes a refrigerant leakage determination system that determines the presence or absence of refrigerant leakage by starting a compressor when the compressor is stopped for a predetermined time in a refrigeration cycle device.

[0003] In this conventional device, after the compressor has operated for a predetermined time, the degree of subcooling at the outlet of the heat source side heat exchanger is detected, and when it is smaller than the target value, it is determined that refrigerant leakage has occurred.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the refrigerant leakage determination system of Patent Document 1, when there is a period of stopping operation for a long time, the compressor is operated every predetermined period, for example, once a day, and the presence or absence of refrigerant leakage is determined from the presence or absence of fluctuations in the heat exchange temperature. That is, since the determination of refrigerant leakage requires a predetermined time, that is, a long period of operation stop, it is not possible to determine refrigerant leakage when the air conditioner is operated almost all day.

Means for Solving the Problems

[0006] To solve the above problems, the air conditioner according to claim 1 of the present invention comprises: a housing having a first intake port, a first outlet port, a second intake port, and a second outlet port; a refrigerant circuit in which a compressor, a condenser, a pressure reducing device, and an evaporator are sequentially connected in a ring by refrigerant piping; a first blower fan provided in a first air supply path from the first intake port through the evaporator to the first outlet port; a second blower fan provided in a second air supply path from the second intake port through the condenser to the second outlet port; a switching means for switching between connecting or closing the downstream side of the first air supply path and the upstream side of the second air supply path; an opening and closing means for opening and closing the first outlet port; an evaporator heat exchanger temperature sensor and a condenser heat exchanger temperature sensor for detecting the temperatures of the evaporator and the condenser; and a control unit that drives the compressor, the first blower fan, and the second blower fan when an operation start command is issued, and controls the opening and closing of the switching means and the opening and closing means. The first and second airflow paths are configured independently, and the control unit acquires the temperature difference Td detected by the evaporator heat exchanger temperature sensor and the condenser heat exchanger temperature sensor. During operation, it opens the switching means to connect the first and second airflow paths, closes the first outlet with the opening / closing means, and further acquires the temperature difference Td=Td1 after a first predetermined time has elapsed. It also enables the execution of a dehumidification detection mode during operation, which closes the switching means to block communication between the first and second airflow paths, opens the first outlet with the opening / closing means, and further acquires the temperature difference Td=Td2 after a second predetermined time has elapsed. After executing either the dehumidification detection mode or the cold air detection mode, the other mode is executed immediately, and if the difference between the temperature difference Td2 and the temperature difference Td1 is within a predetermined range, the operation is stopped and an error is reported.

[0007] Furthermore, in the air conditioner according to claim 2, the control unit is characterized in that it executes the cold air detection mode immediately after executing the dehumidification detection mode.

[0008] Furthermore, in the air conditioner according to claim 3, the control unit is characterized in that the rotation speeds of the first blower fan and the second blower fan are the same in the dehumidification detection mode and the cold air detection mode.

[0009] Furthermore, in the air conditioner according to claim 4, the switching means is installed near the outlet of the first air supply path, the switching means and the opening / closing means are configured as an integrated unit, the opening / closing means closes in conjunction with the opening operation of the switching means, and the opening / closing means opens in conjunction with the closing operation of the switching means.

[0010] Furthermore, the air conditioner according to claim 5 is characterized in that the first blower fan and the second blower fan are rotationally driven by a single motor. [Effects of the Invention]

[0011] According to the present invention, when detecting refrigerant leaks in an air conditioner, it is possible to detect refrigerant leaks during operation even without a predetermined downtime, thus enabling early detection of refrigerant leaks. [Brief explanation of the drawing]

[0012] [Figure 1] This is an external perspective view of an air conditioner showing one embodiment of the present. [Figure 2] This is a plan view of the main components during operation in the cool air mode of the same embodiment. [Figure 3] This is a plan view of the main components during dehumidification mode operation of the same embodiment. [Figure 4] This is a diagram showing the configuration of a refrigeration circuit in the same embodiment. [Figure 5] This is a block diagram of the control circuit of the same embodiment. [Figure 6] This figure shows the airflow path during (A) dehumidification mode operation and (B) cool air mode operation in the same embodiment. [Figure 7] This is a timing chart illustrating the operation of the dehumidification detection mode and the cold air detection mode under normal conditions in the same embodiment. [Figure 8] This is a timing chart illustrating the operation of the dehumidification detection mode and the cold air detection mode in the event of refrigerant leakage in the same embodiment.

Best Mode for Carrying Out the Invention

[0013] Next, an air conditioner according to an embodiment of the present invention will be described based on the drawings. In this embodiment, as an air conditioner, an integrated air conditioner that uses a unit as a cooler or a dehumidifier in a living room will be described.

[0014] The integrated air conditioner is an integrated cooler that incorporates a small-capacity compressor and has a refrigeration circuit when it is not possible to install a separate-type air conditioner or when you want to cool down quickly and locally with cold air. This cooler blows out the cold air cooled by the evaporator toward the user from the front air outlet, and at the same time blows out the warm air exhausted by the condenser from the back. Such a cooler is also used as a dehumidifier for purposes such as drying laundry other than in summer.

[0015] In the following description, "front (front surface)", "rear (rear surface)", "upper", "lower", "right", and "left" follow the definitions in each drawing. The vertical direction is the up-and-down direction, and the horizontal direction is the direction included in the plane direction including the front-back, left-right directions.

[0016] FIG. 1 is an external perspective view of the integrated air conditioner in this embodiment.

[0017] FIGS. 2 and 3 are front views of the main parts during operation in the cooling mode and the dehumidifying mode in this embodiment.

[0018] FIG. 4 is a configuration diagram of the refrigeration circuit in this embodiment.

[0019] The housing 1 of the air conditioner has a bottom plate 2, a right frame 3 and a left frame 4 that engage at the center of the front, upper, and rear surfaces. Inside the housing 1, an evaporator 5, a condenser 6, a compressor 7, and a decompression device 40 of the refrigerant circuit are provided. From the combined surface of the right frame 3 and the left frame 4 at the center of the lower part of the front, a front panel 18 is provided upward.

[0020] The right frame 3 is equipped with a first intake port 12 that draws in indoor air from the center to the top of its right side, and the left frame 4 is equipped with a second intake port 17 that draws in indoor air from the center to the top of its left side.

[0021] The first intake port 12 and the second intake port 17 have filters 13 inside to remove dust from the intake air. The first intake port 12 takes in indoor air with a first blower fan consisting of a centrifugal fan such as a sirocco fan, and the second intake port 17 takes in indoor air with a second blower fan 9, which also consists of a centrifugal fan.

[0022] A first air outlet 19 is provided at the top of the front panel 18. A first air supply path 22 is configured, extending from the first intake port 12 through the evaporator 5 to the first air outlet 19, and a first blower fan 8 is provided in the first air supply path 22. In this embodiment, the first blower fan 8 is provided downstream of the evaporator 5.

[0023] A second air outlet 23 is provided on the upper surface of the housing 1, extending from the rear to the back. A second air supply path 24 is also configured, extending from the second intake port 17 through the condenser 6 to the second air outlet 23, and a second blower fan 9 is provided in the second air supply path 24. In this embodiment, the second blower fan 9 is provided on the downstream side of the condenser 6.

[0024] The first blower fan 8 and the second blower fan 9 are supported by the same rotating shaft extending from the blower motor 10, and rotate at any desired speed to blow air when driven by the blower motor 10. In this embodiment, the first blower fan 8 and the second blower fan 9 are driven by a single motor, but they may be driven by separate motors.

[0025] The first airflow path 22 and the second airflow path 24 are separated by a partition wall 11 and are configured independently of each other. In addition to serving as a partition, the partition wall 11 also fixes and supports the airflow motor 10.

[0026] The first air outlet 19 is provided with vertical louvers 20 and horizontal louvers 21 as opening and closing mechanisms. Multiple vertical louvers 20 are provided to adjust the left-right direction of the airflow and to close the first air outlet 19 when stopped or during dehumidification mode operation described later. Multiple horizontal louvers 21 are provided to adjust the up-down direction of the airflow. In this embodiment, the vertical louvers 20 have two blades, an inner and an outer, formed integrally and substantially parallel to each other. Horizontal louvers 21 are rotatably provided between these two blades, and multiple horizontal louvers 21 are connected to each other by connecting plates (not shown) to keep the angle of each horizontal louver 21 constant.

[0027] Below the first suction port 12, a tank hole 15 is provided for attaching and detaching the drain tank 14. When the drain tank 14 is installed, the outer surface of the drain tank 14 is flush with the outer surface of the right frame 3. Above the first suction port 12, a recess 16 for handling during transport is integrally formed. In addition, the left frame 4 has a recess 16 of the same shape integrally formed in a position opposite to the recess 16 for handling of the right frame 3.

[0028] 26 is a damper installed in the middle of the bypass path 25 inside the housing 1 near the first air outlet 19, and is a switching means whose opening degree can be changed. The bypass path 25 is a path that connects the downstream side of the first air supply path 22 and the upstream side of the second air supply path 24. The damper 26 switches between opening to allow the bypass path 25 to connect, and closing to prevent the bypass path 25 from connecting.

[0029] The damper 26 switches the bypass path 25 to the closed direction, and the vertical louvers 20 switch to the open direction, thereby enabling a cool air mode operation in which the cool air that has passed through the low-temperature evaporator 5 of the first air supply path 22 is blown out from the first outlet 19. This allows the user to cool off with cool air. Meanwhile, the warm air that has passed through the condenser 6 of the second air supply path 24 is blown out from the second outlet 23.

[0030] The damper 26 switches the bypass path 25 to the open direction, and the vertical louvers 20 switch to the closed direction, thereby connecting the first airflow path 22 and the second airflow path 24. Then, the first airflow path 22 is dehumidified by passing through the low-temperature evaporator 5, and the dry hot air, heated by passing through the high-temperature condenser 6, is blown out from the second outlet 23 in dehumidification mode operation. This enables dehumidification and drying of the room.

[0031] The vertical louvers 20 are opened and closed by a louver motor 27a, and the dampers 26 are opened and closed by a damper motor 27b. Stepping motors are used for both the louver motor 27a and the damper motor 27b. The vertical louvers 20 and the dampers 26 may be integrated and opened and closed in conjunction with a single louver motor. In other words, the dampers 26 may close in conjunction with the opening of the vertical louvers 20, and the dampers 26 may open in conjunction with the closing of the vertical louvers 20. Furthermore, when the vertical louvers 20 are closed and the dampers 26 are open, the dampers 26 are connected to the inner blades of the vertical louvers 20, doubly blocking the first air outlet 19, thereby preventing condensation on the outer surface of the vertical louvers 20 due to cold air.

[0032] Reference numeral 28 denotes an operating section located on the front side of the top surface of the housing 1, which includes an operation switch 29 for stopping operation, a mode switch 30 for switching between cool air mode operation and dehumidification mode operation, a timer switch 31, and a number of lamps 32 for displaying the operating status.

[0033] The second air outlet 23 is located from the rear to the back of the top surface of the housing 1, and the direction of the hot air discharge is switched between upward and backward by switching the exhaust louvers 33. The exhaust louvers 33 are flush with the top surface and cover the second air outlet 23 on the top side, exhausting hot air to the rear. By manually rotating them upward by approximately 90 degrees using pivot axes (not shown) located on the left and right sides inside the second air outlet 23 as pivot points, the exhaust louvers 33 protrude slightly beyond the back, cover the second air outlet 23 on the rear side, and exhaust hot air upward.

[0034] The evaporator 5 and condenser 6 are fin-tube type heat exchangers with numerous aluminum fins that have good thermal conductivity and through which copper pipes are passed. A compressor 7 is mounted on the bottom plate 2, and this compressor 7, condenser 6, pressure reducing device 40, and evaporator 5 are sequentially connected by refrigerant piping to form a refrigerant circuit. A drain pan (not shown) is provided below the evaporator 5, and this drain pan collects the condensed water generated in the evaporator 5 and stores it in a drain tank 14.

[0035] 34 is the control unit, and on its input side are switches such as the operation switch 29 and mode selector switch 30 which give the operation start command, as well as a temperature sensor 35, a humidity sensor 36, an evaporator heat exchanger temperature sensor 37a, and a condenser heat exchanger temperature sensor 37b. The temperature sensor 35 and humidity sensor 36 detect the room temperature and humidity. The evaporator heat exchanger temperature sensor 37a and condenser heat exchanger temperature sensor 37b detect the temperature of the refrigerant flowing in the evaporator 5 and condenser 6.

[0036] The output side of the control unit 34 is connected to the blower motor 10, the compressor 7, the louver motor 27a, the damper motor 27b, and the lamp 32. The control unit 34 changes the operating mode and airflow rate in response to switch operations on the operation unit 28 and signals from the sensors 35, 36, and 37. The condenser heat exchanger temperature sensor 37b can estimate the temperature of the compressor 7 by detecting the temperature of the condenser 6 and the refrigerant piping near the condenser 6. As a result, the control unit 34 is equipped with an over-temperature protection unit 39 to prevent the room temperature from rising excessively when operating in cold air mode, which would cause overload operation and activate the overload relay 38 on the compressor 7, shutting off the compressor's power and stopping operation for a long period of time. The pressure reducing device 40 is a pressure reducing device that reduces the refrigerant flowing out of the condenser 6 to a low temperature and low pressure, and is composed of a capillary tube and an expansion valve.

[0037] The overload relay 38 is a safety device installed in the compressor 7 to prevent damage to the compressor 7 when it overheats and approaches its limit temperature (approximately 130°C). It cuts off the power supply to the compressor 7 and stops its operation. The overload relay 38 is made of bimetal, and after activation, it needs to cool down to approximately 80°C to recover. Not only can the compressor 7 not restart for about 20 minutes until the bimetal recovers, but frequent activation of the overload relay 38 will shorten the lifespan of the compressor 7.

[0038] Here, we will explain the airflow path during cool air mode operation. The vertical louvers 20 open the first outlet 19, and simultaneously, the linked damper 26 closes the bypass path 25, separating the first airflow path 22 and the second airflow path 24. As a result, the air drawn in from the first intake port 12 has dust removed by the filter 13, is cooled in the low-temperature evaporator 5, and then passes through the first blower fan 8 before being guided out as cool air from the first outlet 19 by the vertical louvers 20 and the horizontal louvers 21. At the same time, the air drawn in from the second intake port 17 has dust removed by the filter 13, is heated in the high-temperature condenser 6, and is exhausted as warm air from the second outlet 23 after passing through the second blower fan 9.

[0039] Next, the airflow path during dehumidification mode operation will be explained. The vertical louvers 20 close the first air outlet 19, and simultaneously, the linked damper 26 opens the bypass path 25, connecting the first airflow path 22 and the second airflow path 24. As a result, the air drawn in from the first intake port 12 has dust removed by the filter 13 and is cooled in the low-temperature evaporator 5 to remove moisture from the air. After passing through the first blower fan 8, it heads towards the first air outlet 19, but since the first air outlet 19 is closed by the vertical louvers 20 and damper 26, the cool air passes through the bypass path 25 and is sent to the condenser 6. After being heated in the condenser 6, it passes through the second blower fan 9 and dry air is blown out from the second air outlet 23. This dry air is used to dry laundry and dehumidify the room.

[0040] Next, the detection modes for detecting the heat exchanger sensor temperature during dehumidification mode and cooling mode operation will be explained based on Figure 7.

[0041] First, when the user selects the dehumidification mode using the mode selector switch 30 on the control unit 28 and presses the operation switch, the control unit 34 drives the compressor 7 and the blower motor 10 to start dehumidification mode operation. By driving the blower motor 10, the first blower fan 8 and the second blower fan 9 blow air at rotational speed F1. Also, the damper 26 and the vertical louvers 20 remain open and closed, respectively, as when the unit is stopped, and the first airflow path 22 and the second airflow path 24 are in communication.

[0042] Here, the temperature detected by the evaporator heat exchanger temperature sensor 37a is defined as the evaporator heat exchanger temperature Tc, and the temperature detected by the condenser heat exchanger temperature sensor 37b is defined as the condenser heat exchanger temperature Te, with the detected temperature difference Td = Tc - Te. In this case, the operating mode in which the control unit 34 acquires the detected temperature difference Td = Tc1 - Te1 = Td1 of the heat exchanger temperatures after a first predetermined time has elapsed since the start of dehumidification mode operation is defined as the dehumidification detection mode. In the dehumidification detection mode, the detected temperature difference Td1 of the heat exchanger temperatures is measured after a first predetermined time has elapsed since the start of dehumidification mode operation, during which the refrigerant temperatures of the evaporator 5 and condenser 6 have stabilized. In this embodiment, the first predetermined time is set to 15 minutes.

[0043] After the dehumidification detection mode ends, the control unit 34 closes the damper 26, sets the vertical louvers 20 to the open state, closes the bypass path 25 that connects the first air supply path 22 and the second air supply path 24, and starts the cold air mode operation. Note that the operation of the compressor 7 continues, and the operation of the blower motor 10 continues at the rotation speed F1. At this time, after the elapse of the second predetermined time since the start of the cold air mode operation, the control unit 34 sets the operation mode for obtaining the detected temperature difference Td = Tc2 - Te2 = Td2 of the heat exchanger temperature to the cold air detection mode. In the cold air detection mode, after the elapse of the second predetermined time during which the refrigerant temperatures of the evaporator 5 and the condenser 6 stabilize since the start of the cold air mode operation, the detected temperature difference Td2 of the heat exchanger temperature is measured. When starting the cold air detection mode after the end of the dehumidification detection mode, since the change amount of the refrigerant temperatures of the evaporator 5 and the condenser 6 is not larger than the change amount from the start of the operation, the second predetermined time in this embodiment is set to 3 minutes, which is shorter than the first predetermined time.

[0044] When there is no refrigerant leakage and a normal refrigerant circuit is configured, in the dehumidification detection mode, the air cooled by the evaporator 5 is blown to the high-temperature condenser 6, so the heat exchanger temperature of the condenser 6 is lower than that in the cold air detection mode. This is represented by the relationship Tc1 < Tc2 in FIG. 7. On the other hand, although there is a difference in the heat exchanger temperature of the evaporator 5 between the dehumidification detection mode and the cold air detection mode, in either case, the air sucked in from the first suction port 12 first circulates, so the change amount of the heat exchanger temperature is smaller than that of the condenser 6. That is, the temperature difference between Te1 and Te2 is smaller than the temperature difference between Tc1 and Tc2. Therefore, in the normal state, since the relationship Td1 < Td2 holds, the difference (Td2 - Td1) between the detected temperature differences Td2 and Td1 is a significant temperature difference.

[0045] Next, the heat exchanger detection temperatures in the dehumidification detection mode and the cold air detection mode during refrigerant leakage will be described based on FIG. 8.

[0046] In Figure 8, similar to Figure 7, the control unit 34 first detects the evaporator heat exchanger temperature Tc and the condenser heat exchanger temperature Te in dehumidification detection mode, and obtains the detected temperature difference Td = Tc1 - Te1 = Td1. At this time, if refrigerant is leaking from the refrigerant circuit, it becomes difficult to form a refrigeration cycle, so the detected temperature difference Td1 will be a small value of a few degrees Celsius.

[0047] Then, after the dehumidification detection mode ends, the control unit 34 switches to the cold air detection mode and obtains the detected temperature difference Td = Tc2 - Te2 = Td2. Here, even in cold air mode operation, the condition in which a refrigeration cycle is difficult to form remains unchanged, so as shown in Figure 8, Tc2 and Te2 remain almost unchanged. In other words, the detected temperature differences Td1 and Td2 are almost the same value, so the difference between the detected temperature differences Td2 and Td1 (Td2 - Td1) is zero or a very small value (about 1-2°C). Therefore, the control unit 34 compares whether Td2 - Td1 is within a predetermined range where it is a very small value, and if it is within the predetermined range, it determines that a refrigerant leak has occurred, stops the operation of the air conditioner, and notifies the user of the error by flashing the lamp 32, etc.

[0048] Here, the predetermined range in which Td2-Td1 is a very small value is preferably within approximately 2 degrees. This predetermined range should be the range of temperature differences that result from the dehumidifier being unable to maintain its performance due to refrigerant leakage. In other words, if it is within approximately 2 degrees, it can be determined that there is refrigerant leakage and the operation of the air conditioner can be stopped.

[0049] In this embodiment, the air conditioner is stopped before the start of the dehumidification detection mode, and the evaporator heat exchange temperature Tc0 and the condenser heat exchange temperature Te0 are approximately the same value. However, Tc0 and Te0 may be different values, and there may be a temperature difference between them. In other words, even if there is a temperature difference between Tc0 and Te0, after the first predetermined time has elapsed since the start of the dehumidification detection mode, the evaporator heat exchange temperature Tc and the condenser heat exchange temperature Te will be sufficiently stable, so Tc1 and Te1 can be reliably detected.

[0050] Furthermore, in this embodiment, the air conditioner was stopped before the dehumidification detection mode was started, but it may also be performed while it is running. In other words, when the dehumidification detection mode is started, Tc0 and Te0 may be any values ​​during operation, and regardless of whether the air conditioner is operating in dehumidification mode or cool air mode, after the first predetermined time has elapsed since the start of the dehumidification detection mode, the evaporator heat exchanger temperature Tc and the condenser heat exchanger temperature Te will be sufficiently stable, so Tc1 and Te1 can be reliably detected.

[0051] As a result, when an air conditioner is operated continuously throughout the day, even without a predetermined downtime, the dehumidification detection mode and the cooling detection mode can be continuously executed during operation to detect refrigerant leaks. Since refrigerant leaks can be detected as a result of executing the dehumidification detection mode and the cooling detection mode, early detection of refrigerant leaks is possible.

[0052] Furthermore, if a refrigerant leak cannot be detected during operation, the compressor 7 will overheat. In this case, as mentioned above, the overload relay 38 will activate and stop the operation of the compressor 7. However, when the temperature of the compressor 7 decreases, the overload relay 38 will reset and the operation of the compressor 7 will resume. Repeated stopping and starting of the compressor 7 in this way causes repeated overheating of the components inside the housing 1, leading to deterioration and damage, and shortening the lifespan of the compressor 7. Therefore, by performing refrigerant leak detection during operation by executing the dehumidification detection mode and the cold air detection mode of the present invention, damage to components and shortening of the lifespan of the compressor 7 can be prevented.

[0053] Furthermore, in this embodiment, the cold air detection mode is executed immediately after the dehumidification detection mode ends, but the reverse is also possible: the dehumidification detection mode may be executed immediately after the cold air detection mode ends. Regardless of which detection mode is executed first, the control unit 34 only needs to be able to determine whether the detected temperature difference Td2 of the cold air detection mode and the detected temperature difference Td1 of the dehumidification detection mode are within a predetermined range (whether a significant difference occurs), so it does not matter which detection mode is executed first. In this case, it is preferable that the predetermined time of the detection mode executed first is longer than the predetermined time of the detection mode executed later. This ensures that stable evaporator heat exchanger temperature Tc and condenser heat exchanger temperature Te can be obtained regardless of the operating / stopping state of the air conditioner before the start of the previous detection mode. For example, if the cold air detection mode is executed first and the dehumidification detection mode is executed later, the second predetermined time of the first cold air detection mode is 15 minutes, and the first predetermined time of the later dehumidification detection mode is 3 minutes.

[0054] Furthermore, it is preferable to execute the detection modes in the order that the dehumidification detection mode is completed before the cold air detection mode. In this order, the temperature difference Td between the evaporator heat exchanger temperature Tc and the condenser heat exchanger temperature Te tends to increase. Conversely, if the dehumidification detection mode is executed after the cold air detection mode is completed, the temperature difference Td tends to increase before decreasing. Therefore, executing the cold air detection mode after the dehumidification detection mode is more efficient because the change in heat exchanger temperature throughout the entire detection mode is smaller, and the execution time of the detection mode is also shortened.

[0055] Furthermore, it is desirable that the damper 26 in this embodiment be installed near the first air outlet 19 of the first air supply path 22. This makes it easy to integrate the vertical louvers 20 provided at the first air outlet 19 and the damper 26 into a single unit.

[0056] Furthermore, the pressure reducing device 40 in this embodiment may use a capillary tube or an electronic expansion valve with adjustable opening.

[0057] Furthermore, the other configurations used in this embodiment are presented as examples only and are not intended to limit the scope of the invention. It can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0058] 1. Enclosure (air conditioner) 5. Evaporator 6. Condenser 7 Compressor 8. First blower fan 9. Second blower fan 12 First Inlet 17. Second suction port 19 1st outlet 20. Vertical louvers (opening / closing mechanism) 22. First airflow path 23 2nd outlet 24. Second airflow path 26. Damper (switching mechanism) 34 Control Unit 37a Evaporator heat exchanger temperature sensor 37b Condenser heat exchanger temperature sensor 40 Pressure Reducing Device

Claims

1. A housing having a first intake port, a first outlet port, a second intake port, and a second outlet port, A refrigerant circuit in which a compressor, condenser, pressure reducer, and evaporator are sequentially connected in a ring shape by refrigerant piping, A first blower fan is provided in the first airflow path that extends from the first intake port through the evaporator to the first outlet port, A second blower fan is provided in the second airflow path that extends from the second intake port through the condenser to the second outlet port, A switching means for switching between connecting or closing the downstream side of the first airflow path and the upstream side of the second airflow path, The opening and closing means for opening and closing the first air outlet, An evaporator heat exchanger temperature sensor and a condenser heat exchanger temperature sensor for detecting the temperatures of the evaporator and the condenser, The system includes a control unit that drives the compressor, the first blower fan, and the second blower fan when an operation start command is issued, and controls the opening and closing of the switching means and the opening / closing means, The first airflow path and the second airflow path are configured independently. The control unit acquires the temperature difference Td detected by the evaporator heat exchanger temperature sensor and the condenser heat exchanger temperature sensor. During operation, the switching means is opened to connect the first airflow path and the second airflow path, while the opening / closing means closes the first air outlet, and further, a dehumidification detection mode is performed to obtain the detected temperature difference Td = Td1 after a first predetermined time has elapsed. During operation, the switching means is closed to close the communication between the first and second airflow paths, while the opening / closing means opens the first air outlet, and a cold air detection mode is enabled in which the detected temperature difference Td = Td2 after a second predetermined time has elapsed is obtained. An air conditioner characterized by executing either the dehumidification detection mode or the cold air detection mode, then immediately executing the other mode, and stopping operation and issuing an error notification if the difference between the detected temperature difference Td2 and the detected temperature difference Td1 is within a predetermined range.

2. The control unit then executes the cold air detection mode immediately after executing the dehumidification detection mode. The air conditioner according to feature 1.

3. The control unit sets the rotation speed of the first blower fan and the second blower fan to be the same in the dehumidification detection mode and the cold air detection mode. The air conditioner according to feature 2.

4. The switching means is installed near the outlet of the first airflow path. The switching means and the opening / closing means are integrated into one unit. The opening / closing means closes in conjunction with the opening operation of the switching means, and the opening / closing means opens in conjunction with the closing operation of the switching means. The air conditioner according to feature 3.

5. The first and second blower fans are rotated by a single motor. An air conditioner according to any one of features 1 to 4.

Images