JP2010203623A - Air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an air conditioner enabling proper operation by securely performing protection when the pressure of a compressor is increased due to the forgetting of the opening of a stop valve of a gas tube and capable of inexpensively detecting abnormal high pressure at the discharge side of the compressor without using a pressure switch. <P>SOLUTION: During heating operation performed after installation, a specific operation mode is provided for detecting the closing of the gas tube stop valve 22. In the specific operation mode, an operation frequency of the compressor 10 and a detection operation completion time are set in accordance with an outside air temperature at the start of the operation and the operation is performed. When a compressor current value reaches a set value (compressor current determination value) within the detection operation completion time, it is determined that the gas tube stop valve 22a is closed and the compressor 10 is stopped. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an air conditioner in which an indoor unit and an outdoor unit are connected by a connection pipe, and particularly relates to detection of an open / closed state of a stop valve when the air conditioner is installed.

  When a separate type air conditioner is installed, after the indoor unit and the outdoor unit in a state where the refrigerant is sealed are connected by a connection pipe, the heat exchanger of the indoor unit and the vacuum in the connection pipe are connected. A pull is made. Then, after the evacuation is completed, by opening the stop valve of the outdoor unit, the refrigerant in the outdoor unit is released into the connection pipe and the heat exchanger of the indoor unit. Here, if the operator forgets to open a plurality or part of the stop valves of the outdoor unit during the above installation, the air conditioner does not operate properly and the pressure in the refrigerant circuit increases. Significant impact on the safety and reliability of the machine.

  Therefore, as a method for detecting forgetting to open the stop valve, for example, “in the air conditioner (110) provided with the refrigerant circuit (11) of the compression refrigeration cycle, high-pressure refrigerant pressure or compression on the discharge side of the compressor (21)” The low pressure refrigerant pressure on the suction side of the compressor (21) is detected, and when the detected refrigerant pressure is out of the predetermined range within a predetermined time after the operation of the compressor (21) is started, the compressor (21) is turned off. It is determined that the abnormality is forgetting to open the closing valves (14, 15), and the restart of the compressor (21) is prohibited and the abnormality is displayed "(for example, a patent) Reference 1).

JP 2001-280716 A (summary)

  In the separate type air conditioner, a stop valve is provided in the outdoor unit, and before the installation of this device, the stop valve is closed to maintain the refrigerant and keep the clean state. Normally, the refrigerant circulates through the indoor unit and the outdoor unit by opening this stop valve and operating it during installation. On the other hand, if the air conditioner is operated without forgetting to open the stop valve after installation, the refrigerant cannot circulate, resulting in an abnormally high pressure on the discharge side of the compressor, which may reduce the safety and reliability of the air conditioner There was sex.

  Moreover, although what is disclosed by said patent document 1 avoids the above problems, in order to detect the high pressure refrigerant pressure of the discharge side of a compressor, a pressure switch must be provided, There was a problem that the number of parts increased and the price increased.

  The present invention has been made to solve the above-described problems, and a first object is to realize an abnormally high pressure detection on the discharge side of the compressor at a low cost without using a pressure switch. The purpose is to obtain an air conditioner. A second object is to obtain an air conditioner that can reliably protect and operate properly when the pressure of the compressor rises due to forgetting to open the stop valve of the gas pipe. .

  An air conditioner according to the present invention includes an indoor unit, an outdoor unit having a compressor, a connection pipe that connects the indoor unit and the outdoor unit, and a gas pipe stop valve provided in the connection pipe. In the air conditioner, a special operation mode is provided for detecting stop valve closing during heating operation performed after installation, and in the special operation mode, the operation frequency and operation completion time of the compressor according to the outside air temperature at the start of operation When the compressor current value reaches a set value (compressor current determination value) within the operation completion time, it is determined that the gas pipe stop valve is closed, and the compressor Stop.

  According to the air conditioner of the present invention, in the case of forgetting to open the gas pipe stop valve during the heating operation performed after installation, the gas pipe stop valve is not added without adding a pressure detection component or the like. Closed can be detected and the compressor can be stopped below the protection pressure. For this reason, it is possible to operate the air conditioner appropriately, and the safety of the air conditioner and the reliability of the parts can be improved at a low cost.

It is a block diagram which shows the structure of the control apparatus of the air conditioner which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of the control apparatus of the air conditioner which concerns on Embodiment 2 of this invention. It is a parameter control example figure by the outside temperature in operation | movement of the control apparatus of FIG. It is a refrigeration cycle diagram of the air conditioner according to Embodiments 1 and 2 of the present invention. In the air conditioner of FIG. 4, it is the conceptual diagram which showed the compressor pressure and the compressor electric current for every external temperature at the same operating frequency at the time of heating operation in the state where the gas pipe stop valve is closed. In the air conditioner of FIG. 4, it is the conceptual diagram which showed the compressor pressure and the compressor electric current for every operating frequency at the same external temperature at the time of heating operation in the state where the gas pipe stop valve is closed. In the air conditioner of FIG. 4, it is the conceptual diagram which showed the compressor pressure and the compressor electric current for every operating frequency at different external temperature at the time of heating operation in the state where the gas pipe stop valve is closed. It is a flowchart which shows the operation | movement procedure which concerns on Embodiment 2 of this invention. It is a flowchart in the detection driving | operation constant setting of FIG. It is a flowchart which shows the operation | movement procedure which concerns on Embodiment 1 of this invention. It is a flowchart in the detection driving | operation constant setting of FIG.

  Hereinafter, embodiments of an air conditioner according to the present invention will be described with reference to the drawings.

Embodiment 1 FIG.
FIG. 4 is a refrigeration cycle diagram of the air conditioner according to Embodiment 1 of the present description. The refrigeration cycle diagram of FIG. 4 is similarly applied to the second embodiment described later.
The air conditioner of FIG. 4 includes an indoor unit 15 having an indoor heat exchanger 16, an outdoor heat exchanger 18, a compressor 10 that can variably control the compressor frequency by an inverter, and an outdoor unit 17 having a four-way valve 19. A gas side connection pipe 22 and a liquid side connection pipe 23 for connecting the indoor unit 15 and the outdoor unit 17 are provided. In addition, a gas pipe stop valve 22 a is provided in the vicinity of the connection portion of the outdoor unit 17 with the gas side connection pipe 22, and a liquid pipe stop valve 23 a is provided in the vicinity of the connection portion with the liquid side connection pipe 23. Yes. An electronic expansion valve 12 and a capillary tube 21 are attached between the outdoor heat exchanger 18 and the liquid pipe stop valve 23a.

  When the air conditioner is installed, first, the gas pipe stop valve 22a and the liquid pipe stop valve 23a are closed, and the outdoor unit 17 in a state in which the refrigerant is sealed and the indoor unit 15 are connected to the gas side connection pipe. 22 and the liquid side connection pipe 23 are connected to each other, and the evacuation of the indoor heat exchanger 16, the gas side connection pipe 22 and the liquid side connection pipe 23 of the indoor unit 15 is performed. After the evacuation is completed, the gas pipe stop valve 22a and the liquid pipe stop valve 23a of the outdoor unit 17 are opened, so that the refrigerant in the outdoor unit 17 becomes the gas side connection pipe 22 and the indoor heat exchanger 16 of the indoor unit 15. And discharged into the liquid side connection pipe 23.

  Here, if the heating operation of the air conditioner is performed with the gas pipe stop valve 22a closed by mistake, the closed path (space) between the compressor 10 and the gas pipe stop valve 22a via the four-way valve 19 is performed. Since the compressed refrigerant continues to be supplied, the compressor pressure rises abnormally and the compressor current increases in proportion to the pressure. This compressor pressure is characterized by a sharp rise after a certain amount of time has elapsed since the start of compressor operation, and the time until the pressure suddenly rises depends on the outside air temperature during operation and the operating frequency of the compressor. To do.

5 and 6 are conceptual diagrams showing the compressor pressure and the compressor current when the heating operation is performed in a state where the gas pipe stop valve 22a is closed.
The time until the compressor pressure suddenly increases is shorter as the outside air temperature is higher as shown in FIG. 5, and is shorter as the compressor operating frequency is higher as shown in FIG.
For example, as shown in FIG. 5, when the compressor frequency is the same 30 Hz and the outside air temperature is different between 35 ° C. and −15 ° C., the time until the set pressure is reached is 35 ° C. where the outside air temperature is high. Faster (Time 1 <Time 3).
Moreover, as shown in FIG. 6, when the outside air temperature is the same −15 ° C. and the compressor operating frequency is different between 90 Hz and 30 Hz, the time until reaching the set pressure is faster at 90 Hz where the compressor operating frequency is high. (Time 2 <time 3).

  When the relationship between the compressor pressure, the compressor current, and the compressor operating frequency when the heating operation is performed in a state where the gas pipe stop valve 22a is closed is clarified by the above description, the first embodiment will be described next. An air conditioner control apparatus according to the present invention will be described.

FIG. 1 is a block diagram illustrating a configuration of a control device for an air conditioner (outdoor unit) according to the first embodiment.
The control device according to the first embodiment includes a reactor 101 connected to a commercial power source, diode bridges (rectifier circuits) 102 and 103, a smoothing capacitor 104 provided on the output side of the diode bridge 103, and a smoothing capacitor 104. And an inverter circuit 9 connected in parallel. The inverter circuit 9 controls the compressor 10, and the drive current (compressor current) is detected by the current detector 14. The inverter circuit 9 is controlled by the microcomputer 1. The microcomputer 1 takes in the information of the outside air temperature from the outside air temperature detecting means 105 and performs arithmetic processing as described later to control the inverter circuit 9.

  The microcomputer 1 receives an external air temperature information from the external air temperature detecting means 105 and a detection operation constant setting unit 11 that takes in information of the compressor current from the current detection unit 14, and receives information from the detection operation constant setting unit 11 to receive an inverter circuit. 9 has a waveform generation unit 13 that sends a drive signal to 9. The detected operation constant setting unit 11 includes a detected operation time control unit 2, an operation frequency control unit 3, and a current level determination unit 4. The detection operation time control unit 2 sets the detection operation completion time according to the outside air temperature detected at the start of operation, the operation frequency control unit 3 sets the operation frequency according to the outside air temperature, and the current level determination unit 4 The compressor current judgment value is set according to the temperature.

Next, an operation procedure when the special operation mode is performed in the heating operation in the air conditioner of the present embodiment will be described with reference to FIGS. 10 and 11.
FIG.10 and FIG.11 is a flowchart which shows the operation | movement procedure at the time of implementing special operation mode at the time of heating operation in the air conditioner of FIG. The special operation mode is an operation mode for detecting the open / closed state of the gas pipe stop valve 22a during the heating operation performed after installing the air conditioner. In the following description, the gas pipe valve closed detection is detected. Also called driving.

  First, as shown in the flowchart of FIG. 10, when the gas pipe valve close detection operation is started (ST3), constants are set in the gas pipe valve close detection operation (ST4). FIG. 11 is a flowchart showing the operation of the detected operation constant setting unit 11 in the microcomputer 1 of FIG. The operation frequency control unit 3 sets the operation frequency according to the outside air temperature detected at the start of operation (ST4-4), the detection operation time control unit 2 sets the detection operation completion time (ST4-5), and the current level. The determination unit 4 sets a compressor current determination value (ST4-6).

For example, as shown in FIG. 3-1, the detection operation completion time for valve closing is detected operation completion time 1 when the outside air temperature detected before operation is 1 or less, and detection operation completion when the outside air temperature is 2 or more. The time 2 is a constant value, and that value is selected. The detected operation completion time when the detected outside air temperature is between the outside air temperature 1 and the outside air temperature 2 is a value calculated by linear interpolation between the detected operation completion time 1 and the detected operation completion time 2. .
Similarly, the detection operation frequency and the compressor current determination value (current level determination value) are selected according to the outside air temperature. Conceptual diagrams in selecting the values are as shown in FIGS. 3-2 and 3-3.

Here, the compressor operating frequency during the gas pipe valve closing detection operation in step ST4-4 is a constant that affects the pressure increase speed when the valve is closed and the performance of the air conditioner when the valve is opened.
Regarding the pressure increase rate, if the increase rate of the compressor pressure when the gas pipe stop valve 22a is closed is too steep, the inertia due to the power of the compressor 10 even if the compressor 10 is stopped at the set pressure. The set pressure may be greatly exceeded due to error or current detection error. However, the operation can be reliably stopped in the vicinity of the set pressure by reducing the compressor frequency during the gas pipe valve closing detection operation and suppressing the pressure increase rate.

  Further, regarding the performance of the air conditioner, the influence on the blowout temperature of the indoor unit 15 during the gas pipe valve closing detection operation is taken into consideration. When the heating operation is performed with the gas pipe stop valve 22a opened, the blowing temperature of the indoor unit 15 is low when the operating frequency of the compressor 10 is low, and the blowing temperature of the indoor unit 15 is high when the operating frequency is high. . Therefore, by adjusting the compressor frequency according to the target blowout temperature of the indoor unit 15 during the gas pipe valve closing detection operation, it is possible to realize performance close to normal operation.

  The detection operation completion time in step ST4-5 is set for improving the comfort of the air conditioner, and its purpose is to minimize the operation time in the special operation mode of valve closing detection. For example, as shown in FIG. 7, the time to reach the set pressure is time 1 when the outside air temperature is 35 ° C. and the compressor frequency is 30 Hz, and time 2 when the outside air temperature is −15 ° C. and the compressor frequency is 90 Hz. Suppose that By changing this time 1 and time 2 as necessary, it is possible to absorb differences in the refrigerant amount in each air conditioner and differences in piping and heat exchanger specifications, as well as a special operation mode called valve closing detection. It is possible to minimize the operation time of the system.

  The compressor current determination value in step ST4-6 is for determining that the compressor pressure has reached the set pressure. For example, a conceptual diagram of compressor pressure and compressor current when the heater is operated with the valve closed at a compressor frequency of 30 Hz when the outside air temperature is 35 ° C. and at a compressor frequency of 90 Hz when the outside air temperature is −15 ° C. is shown in FIG. 7 as shown. As shown in FIG. 7, when the compressor current reaching the set pressure is 35 ° C. and the compressor frequency is 30 Hz, the judgment value is 3, and when the outside temperature is −15 ° C. and the compressor frequency is 90 Hz, the judgment value is 2. Suppose that By setting this current determination value to the compressor current determination value (current level determination value) according to the outside air temperature as shown in FIG. 3C, the compressor 10 can be operated at a constant pressure even when the outside air temperature changes. Since it can be stopped, the safety and reliability of the air conditioner are improved.

  When the operation constant of the gas pipe valve closing detection operation is determined in this way, the flowchart of FIG. 11 ends, and the operation returns to the flowchart of FIG. 10 to start the operation of the compressor 10 in step ST5. Measurement of the detected operation time is started. At this time, the compressor 10 operates at the compressor frequency set in step ST4-4. The compressor current value is always detected by the current detection unit 14 during operation of the compressor 10 and is sent to the current level determination unit 4 in the microcomputer 1.

  When the operation of the compressor 10 is started and measurement of the detected operation time is started (ST5, ST6), it is determined whether or not the compressor current value has reached the compressor current determination value (current level determination value). Is performed (ST8). If the compressor current has reached the compressor current determination value (ST8: YES), it is determined that the gas pipe stop valve 22a is closed, the compressor 10 is stopped (ST11), and the flow is terminated. To do.

  If the compressor current value does not reach the compressor current judgment value (current level judgment value) during the gas pipe valve closing detection operation (ST8: NO), and the detection operation time has not passed the detection operation completion time (ST9: NO), the process proceeds to step ST8 again to continue the detection operation. When the detected operation time has passed the detected operation completion time (ST9: YES), it is determined that the gas pipe stop valve 22a is normally open, the flow is terminated, and the normal operation is started.

  As described above, in the first embodiment, the special operation mode (gas pipe valve closing detection operation) is executed for detecting the closing of the gas pipe stop valve 22a during the heating operation performed after installation. In the special operation mode, when the compressor operating frequency and operation time are set according to the outside air temperature at the start of operation and the compressor current value reaches the compression current judgment value within the operation completion time. In this case, it is determined that the gas pipe stop valve 22a provided in the gas side connection pipe 22 is closed, and the compressor 10 is stopped. For this reason, at the time of heating operation performed after installation, if the gas pipe stop valve 22a is forgotten to be opened, the compressor can be stopped below the protective pressure without adding a pressure detection component or the like. For this reason, it is possible to operate the air conditioner properly, and it is possible to improve the safety of the air conditioner and the reliability of parts at low cost.

  In the first embodiment, in the special operation mode (gas pipe valve closing detection operation), the operating frequency of the compressor 10 is changed according to the outside air temperature at the start of operation, and the gas pipe stop valve Since the rising speed of the compressor pressure when 22a is closed can be adjusted, detection at the target compressor pressure can be performed reliably.

  Further, in the special operation mode (gas pipe valve closing detection operation), the compressor pressure when the gas pipe stop valve 22a is opened is changed by changing the operating frequency of the compressor 10 according to the outside air temperature at the start of operation. Can be adjusted. For this reason, even in the special operation mode with the gas pipe stop valve 22a opened, erroneous detection can be reliably prevented while minimizing the influence on comfort.

  Also, by changing the detection operation completion time according to the outside air temperature before the start of operation, it is possible to set the time required for the special operation mode (gas pipe valve closed detection operation) different from the normal operation to the minimum necessary Therefore, the time that affects the comfort can be minimized by the special operation mode.

  Further, in the special operation mode (gas pipe valve closing detection operation), the compressor 10 can be operated at a constant pressure even when the outside air temperature changes by changing the compression current determination value according to the outside air temperature before starting the operation. Since it can be stopped, the safety and reliability of the air conditioner are improved.

Embodiment 2. FIG.
Embodiment 2 in which various control functions are added to Embodiment 1 will be described as Embodiment 2.
FIG. 2 is a block diagram showing a configuration of a control device for an air conditioner (outdoor unit) according to Embodiment 2 of the present invention.
The control device of FIG. 2 includes a detection prohibition time setting unit 6 and an electronic expansion valve opening control unit 7 in addition to the detected operation constant setting unit 11 in comparison with the control device of FIG. In addition, a cooling operation integration time determination unit 8 and a detection operation completion storage unit 5 are added to the microcomputer 1. In addition, a display unit 106 for displaying an abnormality is added to the control device of FIG. The detection prohibition time setting unit 6 of the detection operation constant setting unit 11 sets the detection prohibition time. The detection prohibition time is a standby time (prohibition time) from when the compressor 10 is started until the compressor current level is determined. After the detection prohibition time has elapsed, the compressor current level is determined. . The electronic expansion valve opening degree control unit 7 controls the opening degree of the electronic expansion valve 12. The cooling operation integration time determination unit 8 determines whether or not the integration time of the cooling operation exceeds a predetermined time. The detection operation completion storage unit 5 stores information about whether the gas pipe valve closing detection operation has been completed (completed or incomplete).

  The operation of the control device in FIG. 2 will be described using the flowcharts in FIGS. 2, 8, and 9. However, ST3 to ST6 and ST8, ST9, and ST11 in FIG. 10 and ST4-3 to ST4-6 in FIG. 11 represent a common flow.

  First, in the flowchart of FIG. 8, when the operation for starting the operation is performed by the user, the gas pipe valve closing detection operation is completed based on the information stored in the detection operation completion storage unit 5 in the microcomputer 1 of FIG. It is determined whether or not it has been performed (ST1). Here, when the gas pipe valve closing detection operation indicates completion (ST1: YES), the flow ends and the normal operation starts, and when it indicates incompletion (ST1: NO) Then, it is determined whether the operation mode is a heating operation or a cooling operation (ST2). Here, in the case of the heating operation (ST2: heating operation), the gas pipe valve closing detection operation is started (ST3). The information in the detected operation completion storage unit 5 indicates incomplete at the time of shipment.

  Next, when the valve closing detection operation is started (ST3), a detection operation constant is set (ST4). As shown in FIGS. 2 and 1, the detection operation constant is set in addition to the detection operation completion time, the operation frequency, and the compressor current determination value described in the first embodiment, as well as the detection inhibition time. The detection operation constant setting unit 11 sets the opening of the electronic control valve. FIG. 9 is a flowchart showing the operation of the detection operation constant setting unit 11 in the microcomputer 1 of FIG. 2, and the operations from step ST4-3 to ST4-6 described in FIG. 11 are the same.

  The opening of the electronic expansion valve 12 in step ST4-1 is set by the electronic expansion valve opening control unit 7, but the normal operation is performed when the compressor current determination value for determining that the valve is closed and the gas pipe stop valve 22a is open. This is used to adjust the difference from the compressor current value in this case and secure a current margin in detection. In a gas pipe valve closing detection operation with a fixed frequency (for example, 60 Hz) under a specific temperature condition (for example, 0 ° C.), compression when the gas pipe stop valve 22a is opened and a heating operation is performed for a predetermined detection operation time (for example, 5 minutes) When the opening of the electronic expansion valve 12 is 5.3 A for 200 pulses and 3.3 A for 400 pulses, the compressor current determination value for determining that the gas pipe stop valve 22a is closed is 5.5 A. If the opening is 200 pulses, the difference between the compressor current judgment value when the valve is closed and the peak current value during heating operation when the valve is open is as small as 0.2A, so the gas pipe stop valve 22a is closed accidentally. There is a possibility of false detection. However, when the opening degree of 400 pulses is selected, the difference between the compressor current determination value when the valve is closed and the peak current during heating operation when the valve is opened is as large as 2.2A. In this way, fixing the opening of the electronic expansion valve 12 can prevent erroneous detection.

  Although the detection prohibition time is set in step ST4-2 by the detection prohibition time setting unit 6, this is also set to prevent erroneous detection as in the case of the electronic expansion valve 12. In general, the compressor 10 supplies a large amount of compressor current for a few seconds after startup in order to prevent the compressor motor from stepping out due to insufficient torque. Therefore, the compressor current may increase up to the compressor current determination value for several seconds after the compressor is started even when the gas pipe stop valve 22a is open. For this reason, the valve closing detection determination process is prohibited until the detection prohibition time (for example, 10 seconds) elapses from the start of the compressor.

  When the detection operation constant is set in step ST4, the flow returns to the flowchart of FIG. 8 to start the operation of the compressor (ST5), and the measurement of the detection operation time is started (ST6).

Here, if the detected operation time does not reach the detection prohibited time (ST7: NO), the process proceeds to the determination as to whether or not the detected operation completion time has been reached (ST9), and if the detected operation completion time has not been reached (ST9). (ST9: NO) returns to the detection prohibition time determination flow again (ST7). This flow is continued until the detection inhibition time elapses.
When the operation time of the gas pipe valve closing detection operation reaches the detection prohibition time (ST7: YES), the process proceeds to the next step to determine the current level (ST8).

  When the compressor current reaches the compressor current judgment value (ST8: YES) and the compressor is stopped (ST11), an abnormality is displayed on the indoor unit 15 and the outdoor unit 17 (ST12), and to the user. Notification of. This abnormality display is made by the display unit 106 in the example of FIG. The user can take appropriate measures by knowing that a problem has occurred due to the abnormal display and the cause thereof. Further, in this case, in order to prevent re-operation with the gas pipe stop valve 22a being closed, the air conditioner can be restarted only when the power supply is reset without automatically returning the compressor 10. Then, since the operation time of the valve closing detection operation has not passed the detection operation completion time, the detection operation completion storage unit 5 ends the flow with the information indicating “incomplete”.

Next, the case where the compressor current does not reach the compressor current determination value during the detection operation (ST8: NO) and the detection operation time has elapsed (ST9: YES) will be described.
In this case, since it can be determined that the stop valve 22a is normally opened, the information in the detection operation completion storage unit 5 in FIG. 2 is changed to information (completion) indicating completion of the gas pipe valve closing detection operation. (ST10). By storing this information, the conditions for performing the gas pipe valve closing detection operation can be limited only to specific cases until it is determined that the stop valve 22a is open.

  On the other hand, when the cooling operation is selected in step ST2 (ST2: cooling operation), the operation of the compressor 10 is started (ST13), and the measurement of the cooling operation integration time is started (ST14). The cooling operation integration time indicates 0 when the outdoor unit 3 of the air conditioner is shipped, and indicates the total time that the air conditioner has been operated in the cooling mode.

Here, when the cooling operation integration time has exceeded the set time (for example, 36 hours) by the cooling operation integration time determination unit 8 (ST15: YES), it is determined that the gas pipe stop valve 22a is normally opened and detected. The information in the operation completion storage unit 5 is changed to information indicating “completed” (ST10).
In Step ST15, when the cooling operation is finished without reaching the set time for the cooling operation (ST15: NO), the flow is finished without changing the information regarding the completion of the gas pipe valve closing detection operation.

  The current detection method of the compressor 10 in FIG. 1 is not limited to the method of detecting the current of two phases out of the three phase currents of the compressor 10 as shown in FIG. Or a method of detecting a direct current obtained by synthesizing the currents of the three phases of the compressor 10.

  Further, the method for setting the valve closing detection operation completion time, the detection operation frequency, and the compressor current determination value (current level determination value) in FIG. 3 is an example, and is not limited to the form of the graph in FIG.

  As the outside air temperature detecting means 105 at the start of operation, it is possible to use an outside air temperature thermistor, a defrosting thermistor, a discharge temperature thermistor, etc. mounted on the outdoor unit (see FIG. 4).

  The abnormality display in step ST12 may be performed only on the indoor unit 15 or only on the outdoor unit 17, or only means for storing the information in the microcomputer 1 may be used. There is also a method of selecting and using the combination. Further, in addition to the abnormality display, it may be notified by voice that an abnormality has occurred.

  As described above, in the second embodiment, when the compressor current does not reach the compressor current determination value even after the operation completion time has elapsed, it is determined that the gas pipe stop valve 22a is normally opened. Therefore, it shifts to normal operation. For this reason, since the transition from the special operation mode to the normal operation (heating operation) is automatically performed, the heating operation after installation is made uncomfortable at the normal time.

  In the second embodiment, the opening degree of the electronic expansion valve 12 is fixed during operation in the special operation mode (gas pipe valve closing detection operation). The difference from the peak current value during the heating operation when the gas pipe stop valve 22a is opened is increased to prevent erroneous detection.

  Further, until the set time elapses from the start of the compressor, a large amount of compressor current may flow even in a normal state. In the second embodiment, whether or not the gas pipe stop valve 22a is closed during this period. Judgment is prohibited and false detection is prevented.

  Further, in the special operation mode, the outside air temperature detecting means 105 is necessary. For this purpose, in addition to providing a thermistor for detecting the outside air temperature, it is possible to use an existing thermistor mounted on an outdoor unit. It is possible to prevent an increase.

  Further, information indicating whether or not the operation in the special operation mode (gas pipe valve closing detection operation) is completed is stored in the detection operation completion storage unit 5, and the operation in the special operation mode is performed only when the operation is not completed. Yes. For this reason, the execution conditions of the special operation mode can be limited to specific cases until it is determined that the gas pipe stop valve 22a is open.

  Further, since the display means for displaying an abnormality when it is determined that the gas pipe stop valve 22a is closed is provided in at least one of the indoor unit 15 and the outdoor unit 17, the user can grasp the abnormal state, This abnormality (valve closing) can be dealt with.

  In addition, when the cooling operation time is accumulated and the accumulated time reaches the set time, it can be determined that the gas pipe stop valve 22a is normally opened. Therefore, it is necessary to perform the operation in the special operation mode during the heating operation. In such a case, the operation in the special operation mode is not performed, and the meaningless special operation mode can be avoided.

  1 microcomputer, 2 detection operation time control unit, 3 operation frequency control unit, 4 current level determination unit (compressor phase current), 5 detection operation completion storage unit, 6 detection prohibition time setting unit, 7 electronic expansion valve opening control unit , 8 Cooling operation integration time determination unit, 9 Inverter circuit, 10 Compressor, 11 Detection operation constant setting unit, 12 Electronic expansion valve, 13 Waveform generation unit, 14 Current detection unit, 15 Indoor unit, 16 Indoor heat exchanger, 17 Outdoor unit, 18 outdoor heat exchanger, 19 four-way valve, 21 capillary tube, 22 gas side connection pipe, 22a gas pipe stop valve, 23 liquid side connection pipe, 23a liquid pipe stop valve, 25a, 25b, 25c, 25d, 25e, 25f thermistor.

Claims (9)

In an air conditioner including an indoor unit, an outdoor unit having a compressor, a connection pipe connecting the indoor unit and the outdoor unit, and a gas pipe stop valve provided in the connection pipe,
A special operation mode is provided for detection of the gas pipe stop valve closing during heating operation performed after installation,
In the special operation mode, when the compressor operating frequency and the detection operation completion time are set according to the outside air temperature at the start of operation and the compressor current value reaches the set value within the detection operation completion time. The air conditioner determines that the gas pipe stop valve is closed and stops the compressor.   When the compressor current does not reach a set value even after the detection operation completion time elapses, it is determined that the gas pipe stop valve is normally opened, and the normal operation is performed. 1. The air conditioner according to 1.   The compressor current setting value used as a reference for determining whether or not the gas pipe stop valve is closed in the special operation mode is changed according to the outside air temperature at the start of operation. 2. The air conditioner according to 2.   In the operation in the special operation mode, the opening degree of an electronic expansion valve provided between the heat exchanger of the outdoor unit and the heat exchanger of the indoor unit is fixed. An air conditioner according to any one of the above.   The air conditioner according to any one of claims 1 to 4, wherein in the special operation mode, a thermistor mounted on an outdoor unit other than the outside air temperature thermistor is used as a means for detecting the outside air temperature.   The air conditioner according to any one of claims 1 to 5, wherein it is prohibited to determine whether or not the gas pipe stop valve is closed until a set time has elapsed since the start of the compressor.   The information indicating whether or not the operation in the special operation mode is completed is stored, and the operation in the special operation mode is performed only when the operation is not completed. Air conditioner.   The air according to any one of claims 1 to 7, wherein a display means for displaying an abnormality when it is determined that the gas pipe stop valve is closed is provided in at least one of the indoor unit and the outdoor unit. Harmony machine.   When the cooling operation time is integrated and the cooling operation integration time reaches the set time, it is determined that the gas pipe stop valve is normally opened, and the operation in the special operation mode is not performed during the heating operation. The air conditioner according to claim 1.

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