KR20100079407A - Air conditioner and operating method thereof - Google Patents

Abstract

PURPOSE: An air conditioner and an operation method thereof are provided to effectively control indoor temperature by controlling the flow rate of a refrigerant and preventing a refrigerant leak. CONSTITUTION: An air conditioner comprises multiple indoor units. The indoor unit comprises an electronic expansion valve, a temperature sensor, an indoor unit controller, and a valve controller. The electronic expansion valve controls the flow rate of a refrigerant. The temperature sensor measures the temperature of a refrigerant pipe. The indoor unit controller controls the electronic expansion valve using the measured temperature. The valve controller gradually closes the electronic expansion valve.

Description

Air conditioner and operating method

The present invention relates to an air conditioner and an operation method thereof, and more particularly, to an air conditioner and an operation method for preventing leakage of a refrigerant by improving the opening degree of an electronic expansion valve provided in an indoor unit and improving operation efficiency. will be.

The air conditioner is installed to provide a more comfortable indoor environment for humans by discharging cold air into the room to adjust the indoor temperature and purifying the indoor air to create a comfortable indoor environment. In general, an air conditioner includes an indoor unit which is configured as a heat exchanger and installed indoors, and an outdoor unit which is configured as a compressor and a heat exchanger and supplies refrigerant to the indoor unit.

The air conditioner is separated and controlled by an indoor unit composed of a heat exchanger and an outdoor unit composed of a compressor and a heat exchanger, and is operated by controlling power supplied to the compressor or the heat exchanger. In addition, the air conditioner may be connected to at least one indoor unit to the outdoor unit, the refrigerant is supplied to the indoor unit according to the requested operating state, the operation is operated in the cooling or heating mode.

The air conditioner operates in response to the operation set in the indoor unit. When the indoor unit which has been stopped is operated, the degree of opening of the electromagnetic expansion valve cannot be checked. Therefore, the valve is initialized and the electromagnetic expansion valve of the indoor unit is completely closed. After opening it completely, check the opening degree and perform the operation.

However, even when the initial operation of the indoor unit electronic expansion valve is initialized and driven as described above, the operation is performed according to the initial operation for the indoor unit operated among the plurality of indoor units, and the powered-off indoor unit is excluded from the initial driving, Not only is it difficult to confirm the opening degree of the electromagnetic expansion valve through operation, but it is recognized that the electromagnetic expansion valve is completely closed with respect to a predetermined indoor unit, but it is actually open.

When the electronic expansion valve is opened in the indoor unit stopped in this way, the shape of the refrigerant leaks to the indoor unit stopped operation occurs, there is a problem that the other indoor unit can not perform normal performance.

An object of the present invention is to control the electronic expansion valve in the indoor unit, when the electronic expansion valve is closed or closed, so that additional valve locking operation is performed, so that the opening degree of the electronic expansion valve is precisely adjusted, and accordingly the electronic expansion The present invention provides an air conditioner and a method of operating the same, which prevent leakage of refrigerant caused by incomplete opening of the valve.

In the air conditioner according to the present invention, an air conditioner including a plurality of indoor units, wherein the indoor unit senses a temperature for measuring a refrigerant pipe temperature for controlling a flow rate of a refrigerant, a refrigerant inlet part of a indoor heat exchanger, and a refrigerant pipe part of a refrigerant discharge part; The indoor unit control unit and the indoor unit control unit may be configured to calculate a temperature difference between the refrigerant discharge unit and the refrigerant suction unit by using the temperature value measured by the temperature sensing unit, and to control the electronic expansion valve in response to the temperature difference. In response to the control command for the control, the valve control unit for controlling the expansion valve to be closed step by step.

In addition, the operation method of the air conditioner according to the present invention is to calculate the temperature difference by measuring the temperature of the refrigerant suction part and the refrigerant discharge part of the indoor heat exchanger during the initial operation of the indoor unit, the step of initializing the electronic expansion valve, the indoor unit operation stops, And controlling the electromagnetic expansion valve to be in a closed state when the temperature difference is greater than or equal to a reference value.

The air conditioner and its operation method according to the present invention configured as described above, by additionally controlling the electronic expansion valve of the indoor unit is turned off with respect to the indoor unit included in the air conditioner, by accurately controlling the opening degree of the electronic expansion valve in the indoor unit, the refrigerant Even if the indoor unit is stopped or the electronic expansion valve is recognized as closed, it prevents the refrigerant from leaking due to the partial opening and improves the temperature control accordingly, thus improving the efficiency of the operation of the air conditioner. It is greatly improved and has an effect of providing a more comfortable indoor environment.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a block diagram showing the configuration of an air conditioner according to an embodiment of the present invention.

Referring to FIG. 1, an air conditioner according to the present invention includes a plurality of units such as indoor units I11 to I14, I21 and I22 that discharge cold air into a room, and outdoor units O1 and O2 connected to an indoor unit. . In addition, the air conditioner includes a local controller (R11 to R14, R21, R22) connected to the indoor unit for inputting an operation command to the indoor unit. In addition, it may further include a remote controller (not shown) connected to the plurality of units to control and monitor its operation.

Here, the unit included in the air conditioner may include an indoor unit (I) and an outdoor unit (O), and may further include a unit such as an air cleaning unit, a ventilation unit, a humidification unit, a dehumidification unit, and a heater. ) And the outdoor unit (O) is described as an example, but may also be applied to the case where the above unit is connected.

The outdoor unit O (O1, O2) is composed of a compressor and a heat exchanger, and compresses or heat exchanges the refrigerant to supply the refrigerant to the indoor unit according to the operating condition of the air conditioner. The outdoor unit O may be connected to a plurality of indoor units, and in some cases, the outdoor units may be connected to a plurality of indoor units and may supply refrigerant to an indoor unit to which each outdoor unit is connected, or a plurality of outdoor units may supply refrigerant to a plurality of indoor units.

When the plurality of outdoor units supply the refrigerant to the plurality of indoor units, the air conditioner may further include a distributor, and the refrigerant of the outdoor unit is delivered to each indoor unit through the distributor.

The outdoor unit (O) is a compressor for receiving and compressing a refrigerant, an outdoor heat exchanger for exchanging refrigerant and outdoor air, an outdoor fan, an accumulator for extracting gas refrigerant from a supplied refrigerant, and supplying a compressor to the compressor, and a flow path of a refrigerant for heating operation. It includes four-way valve of choice. The apparatus may further include a pressure sensor measuring a pressure of the refrigerant discharged from the compressor and a pressure of the refrigerant supplied to the compressor, and a temperature sensor connected to the refrigerant pipe to measure the temperature of the refrigerant. In addition, a plurality of sensors, valves and oil recovery devices, etc. are further included, but a description thereof will be omitted below.

At least one indoor unit (I) may be provided in one room, and one or more outdoor units (O1, O2) are driven by the request of at least one of the plurality of indoor units (I11 to 14, I21, and I22). As the cooling / heating capacity is changed corresponding to the indoor unit, the number of operation of the outdoor unit and the number of operation of the compressor installed in the outdoor unit vary.

The outdoor unit and the indoor unit are connected through a refrigerant pipe to perform cooling or heating operations according to the flow of the refrigerant according to the flow of the refrigerant, and transmit and receive data to each other according to a predetermined communication method.

 The local controller R (R11 to R14, R21, R22) is connected to the indoor units I11 to I14, I21, and I22 to display the operation status of the connected indoor unit, and to transmit the control command corresponding to the input data f to the indoor unit. send. At this time, the local controller (R) may be connected to the indoor unit by wire or wirelessly, one-way or two-way communication is possible according to the communication method.

The air conditioner may further include a remote controller connected to a plurality of units such as an outdoor unit and an indoor unit to control its operation. The remote controller not only controls and monitors a plurality of connected units, but also sets an operation schedule of each unit and controls the operation according to the set schedule.

FIG. 2 is a diagram illustrating a configuration of the indoor unit of FIG. 1.

As shown in FIG. 2, the indoor unit I (I11 to 14, I21 and I22) includes an indoor heat exchanger 10, an indoor unit fan 50, an expansion valve 20 to expand the refrigerant supplied from the outdoor unit, A plurality of sensors 41, 42, 43, filters 31, 32 are included.

The indoor heat exchanger 10 allows the refrigerant supplied from the outdoor unit to condense or evaporate through heat exchange. In the cooling operation, the evaporator is operated, and in the heating operation, the condenser is operated.

That is, during the cooling operation, the liquid refrigerant of high temperature and high pressure is supplied from the outdoor unit to the indoor unit through the filter 31, expanded through the electromagnetic expansion valve 20, and supplied to the indoor heat exchanger 10, which is an evaporator, to be heat exchanged. As a result, it is discharged to the low-temperature gas refrigerant. At the time of heating operation, the gas refrigerant of high temperature and high pressure is supplied from the outdoor unit to the indoor heat exchanger 10 which is a condenser, and is heat exchanged to discharge the liquid refrigerant of high temperature and high pressure.

The indoor fan 50 smoothly heat exchanges the indoor heat exchanger 10, and introduces air into the indoor heat exchanger 10 in order to discharge cold air into the room.

The indoor unit configured as described above is controlled by a control configuration that supplies power to each unit and transmits control commands.

3 is a block diagram illustrating a control configuration of the indoor unit of FIG. 2.

Referring to FIG. 3, as described above, the indoor unit I includes an indoor heat exchanger 10, an electromagnetic expansion valve 20, an indoor fan 50, and the like, and the indoor unit communication unit 270 and the input unit 280. , The control unit 290, the temperature sensing unit 22, the valve control unit 230,), the fan control unit 250, the indoor fan 50, the wind direction control unit 260 and each component as described above It includes a indoor unit controller 210 for transmitting and controlling the overall outdoor unit operation.

In addition, the indoor unit (I) may be classified into a ceiling type, a stand type, a wall-hung type, etc., depending on the shape thereof, and may have differences in the configuration and arrangement provided according to the type thereof. The description of other configurations will be omitted.

The indoor unit communication unit 270 includes at least one communication module and transmits and receives data to and from other units such as the outdoor unit O, the local controller R, and other indoor units using a predetermined communication method. In some cases, when the air conditioner is provided with a remote controller, data may be transmitted to and received from the remote controller.

The input unit 280 includes input means such as a predetermined number of switches, buttons, touch pads, and dials, and inputs data such as an operation mode, an operation setting, a schedule, and the like for indoor unit operation.

The output unit 290 is provided with at least one output means such as a display means, a speaker, a lamp, and outputs an operating state of the indoor unit. The output unit 290 outputs not only setting information such as setting temperature, setting air volume, and operation mode input through the input unit 280, but also information such as current operation state and room temperature information, and when an error occurs, a warning sound warning light warning message is displayed. Print at least one.

In this case, the input unit 280 and the output unit 290 may be provided in the front panel, the lower surface, the lower portion, the upper portion of the front of the indoor unit (I), the position is not limited to this description.

The temperature sensing unit 220 is connected to the plurality of temperature sensors, and applies the temperature value of the point where each temperature sensor is installed to the indoor unit controller 210. For example, the temperature sensing unit 220 includes first to third temperature sensors 41, 42, and 43, and the number of temperature sensors may vary.

The first temperature sensor 41 is provided at one side of the refrigerant pipe connected to the indoor heat exchanger 10, and measures the temperature of the refrigerant pipe for the refrigerant discharged or sucked as the indoor unit I is cooled or heated. .

The second temperature sensor 42 is provided on the other side of the refrigerant pipe connected to the indoor heat exchanger 10, that is, on the side opposite to the first temperature sensor 42, and is discharged as the indoor unit I is cooled or heated. Measure the temperature of the refrigerant pipe for the refrigerant to be sucked in or sucked in.

When the indoor unit I is cooled, the second temperature sensor 42 measures the refrigerant temperature sucked into the indoor heat exchanger 10, and the first temperature sensor 41 is discharged from the indoor heat exchanger 10. Measure the temperature of the refrigerant. On the other hand, during the heating operation, the first temperature sensor 41 measures the refrigerant temperature sucked into the indoor heat exchanger 10, and the second temperature sensor 42 measures the temperature of the refrigerant discharged from the indoor heat exchanger 10. Measure

The third temperature sensor 43 is installed before or after the indoor fan 50 or the indoor fan, and measures the temperature of air exposed to the room by the indoor fan 50. That is, the third temperature sensor 43 measures the blowout temperature which is the temperature of the air discharged from the indoor unit to the room.

The valve controller 230 controls the opening amount of the electromagnetic expansion valve 20 in response to the control command of the indoor unit controller 210. At this time, the valve control unit 230 controls the degree of opening in accordance with the control command of the indoor unit control unit 210, but further control step by step. For example, the valve control unit 230 controls the electronic expansion valve 20 to be closed or controls the additional expansion even if the electromagnetic expansion valve 20 is closed, so that the electromagnetic expansion valve 20 is completely closed. To be

At this time, the valve control unit 230 determines the degree of opening of the electromagnetic expansion valve 20 in response to the refrigerant pipe temperature measured by the temperature sensing unit 220, and further controls.

The electromagnetic expansion valve 20 changes the opening amount in response to a power supply and a control command supplied from the valve control unit 230. Accordingly, the flow rate of the refrigerant passing through the electromagnetic expansion valve 20 is adjusted.

The fan control unit 250 includes a motor connected to the indoor unit fan 50, controls an operation power of the motor and controls a rotation speed of the motor to control the rotation operation of the indoor unit fan 50. At this time, the fan control unit 250 rotates as the indoor unit I cools or heats, and adjusts the rotation speed according to the control command of the indoor unit control unit 210 corresponding to the set air volume.

The wind direction controller 260 adjusts the direction of cold and hot air discharged into the room by the indoor fan 50 in response to the control command of the indoor unit controller 210. The air volume control unit 260 controls the airflow by controlling the angle of the louver or vane provided in the indoor unit discharge port.

The wind direction controller 260 controls the airflow by changing the left and right angles of the discharged airflow and the vertical angles of the airflow. At this time, the air volume control unit 260 includes a plurality of motors connected to the louvers or vanes provided in the discharge port.

The indoor unit controller 210 allows the air conditioner to be cooled or heated with temperature or air volume in the setting corresponding to the operation mode or the operation setting set through the input unit 280.

At this time, the indoor unit controller 210 determines the operation or stop of the indoor unit in response to the temperature values detected by the plurality of temperature sensors of the temperature sensor 220, generates a control command accordingly, and applies them to each unit.

The indoor unit controller 210 applies a control command to the valve controller 230 to open the electronic expansion valve 20 when the indoor unit starts to operate, and closes the electromagnetic expansion valve 20 when the indoor unit is stopped. The control command is applied to the controller 230.

In addition, the indoor unit controller 210 calculates a temperature difference between the refrigerant intake unit and the discharge port by using the temperature value detected by the temperature sensor 220 at the request of the valve controller 230, and calculates the value of the valve controller 230. Is applied.

The valve controller 230 receives the temperature difference data of the indoor unit controller 210 and additionally controls the electromagnetic expansion valve 20 accordingly.

FIG. 4 is an exemplary view illustrating a change in the opening amount with time of the electronic expansion valve of the indoor unit of FIG. 2. At this time, Figure 4 is a diagram showing the pulse value of the electromagnetic expansion valve according to the change in the opening amount of the electromagnetic expansion valve corresponding to the indoor unit operating state.

Referring to FIG. 4, the valve control unit 230 adjusts the opening amount of the electromagnetic expansion valve 20 according to a control command of the indoor unit controller 210 during indoor unit operation.

The indoor unit controller 210 controls the operation for stopping the operation when the indoor unit is stopped, such as when the indoor temperature reaches the set temperature and satisfies the condition, or when an operation stop command is input, or when a specified schedule ends. The valve control unit 230 and the fan control unit 250 are applied to the air volume control unit 260.

 When controlling the electronic expansion valve 20 to close according to the indoor unit operation stop, the valve control unit 230 controls the electronic expansion valve opening degree to close after initializing the degree of opening of the electronic expansion valve.

At this time, the valve control unit 230 controls the electronic expansion valve to be fully closed after being completely closed and then to be completely closed again. At this time, the electromagnetic expansion valve 20 represents 460 pulses in the fully open state 111 and 0 pulse values in the fully closed state.

The valve control unit 230 is configured such that the electromagnetic expansion valve 20 is closed at the first time T1 when the electromagnetic expansion valve is fully opened (111) at 460 pulses during operation or when the electronic expansion valve is partially opened at a lower value or less. To control. Accordingly, the electromagnetic expansion valve 20 is changed to the closed state while the pulse value is reduced (112).

At this time, the valve control unit 230 does not control to be 0 pulses when the electronic expansion valve 20 is closed, but by controlling the value to 0 pulse or less, for example, -200 pulse value, the electromagnetic expansion valve 20 To be completely closed (113).

That is, even if the electronic expansion valve 20 is in the closed state (T2), the valve control unit 230 controls a pulse value of 0 or less so that the electromagnetic expansion valve 20 is completely closed by applying a control command to close more.

The valve control unit 230 increases the pulse value to open again when the electronic expansion valve 20 is completely closed (T2, T3) 113. Accordingly, the electromagnetic expansion valve 20 gradually opens in the closed state 113 (114), and becomes a fully open state (T4) 115.

The valve control unit 230 controls the opening degree of the electromagnetic expansion valve 20 to be closed when the electromagnetic expansion valve 20 is opened.

The valve control unit 230 controls the electromagnetic expansion valve 20 to be closed at the fifth time T5 and correspondingly closes the valve while reducing the pulse value of the electromagnetic expansion valve 20 (116).

When the electronic expansion valve 20 is closed at the sixth time (117), the valve controller 230 requests the temperature difference data for the refrigerant pipe to the indoor unit controller 210, and the refrigerant suction unit from the indoor unit controller 210. And the temperature difference data of the discharge portion are applied, and it is determined whether the electromagnetic expansion valve 20 is completely closed in response to the temperature difference.

When the temperature difference is greater than or equal to the reference value, the valve control unit 230 determines that the electromagnetic expansion valve 20 is not completely closed, and controls the electronic expansion valve to close by the unit pulse value in the seventh time T7 (118).

Thereafter, the valve control unit 230 requests the temperature difference data to the indoor unit controller 210 to determine the opening state of the electronic expansion valve 20, and to close the unit pulse value again in the eighth time T8 after a predetermined time. The expansion valve 20 is controlled. The valve controller 230 controls the electronic expansion valve 20 to be closed by a unit pulse value at predetermined time intervals using the temperature difference data.

When the temperature difference data is less than the reference value, the valve control unit 230 determines that the electromagnetic expansion valve 20 is completely closed, and ends the valve control.

FIG. 5 is an exemplary view illustrating another example of the change in the amount of opening of the electronic expansion valve of the indoor unit of FIG. 2 according to time. 5 is a view showing the change in the opening amount of the electromagnetic expansion valve according to the opening control of the electromagnetic expansion valve according to the start of the indoor unit operation.

Referring to FIG. 5, when the indoor unit operation starts, the indoor unit controller 210 applies a control command to the valve controller 230 to initialize the electronic expansion valve 20. At this time, the valve controller 230 initializes by controlling the opening amount of the electromagnetic expansion valve 20, and then controls the opening degree in response to the control command of the indoor unit controller 230.

The valve control unit 230 allows the electromagnetic expansion valve 20 to be closed by reducing the pulse value of the electromagnetic expansion valve 20 in a fully open state (P21).

The valve control unit 230 controls the electromagnetic expansion valve 20 to close to -200 pulses, and controls the opening amount by gradually increasing the pulse value at predetermined time intervals of the electromagnetic expansion valve 20.

That is, when the first unit time elapses, the pulse value is increased by the reference pulse (122), and when the first unit time elapses, the pulse value is further increased by the reference pulse (123). This process is repeated (124, 125, 126), and when the target pulse value is reached, the state is maintained (127).

Thereafter, during operation of the indoor unit, the valve control unit 230 controls the opening amount of the electromagnetic expansion valve 20 in response to a request of the indoor unit control unit 210.

Looking at the operation according to an embodiment of the present invention configured as described above are as follows.

6 is a flowchart illustrating an operation method according to the control of the opening amount of the electromagnetic expansion valve in the indoor unit of the air conditioner according to an embodiment of the present invention.

Referring to FIG. 6, when the indoor unit is initially started (S410), the indoor unit controller 210 controls the valve controller 230 to initialize the electronic expansion valve.

The valve control unit 230 controls to open completely regardless of the current state of the electronic expansion valve 20, and then controls to completely close again to perform initialization (S420).

When the indoor unit controller 210 inputs an operation command 430, the indoor unit controller 210 applies a control command to the valve controller 230 so that the electromagnetic expansion valve 20 is opened in response to the load, and the valve controller 230 responds to the control command. The degree of opening is adjusted by controlling the pulse value of the electromagnetic expansion valve 20 (S500).

The indoor unit controller 210 allows the indoor fan S510 to operate and starts the indoor unit operation (S510).

On the other hand, after the initialization of the electronic expansion valve 20, when a separate operation command is not input or when the setting does not satisfy the operating conditions in the standby state, the indoor unit controller 210 is the refrigerant through the temperature sensing unit 240 Measure the piping temperature at. At this time, the flow of the refrigerant is changed according to the indoor unit operation mode.

At this time, the temperature detection unit 240 measures the respective temperatures through the temperature sensor provided in the refrigerant intake port and the refrigerant discharge port of the indoor heat exchanger (S440), and applies them to the indoor unit controller 210.

The indoor unit controller 210 calculates a temperature difference between the refrigerant discharge port and the refrigerant suction port by using the piping temperature of the refrigerant inlet port and the piping temperature of the refrigerant discharge port (S450), and compares the temperature difference with a reference value (S460).

The indoor unit controller 210 applies a control command to the valve controller 230 to close the electromagnetic expansion valve when the temperature difference is equal to or greater than the reference value, and the valve controller 230 controls the electromagnetic expansion valve to be closed by a unit value accordingly ( S470).

If the temperature difference is less than the reference value or after the closing control as described above, until the predetermined time is set (S480), if the operation command is not input (S490), the indoor unit controller calculates the temperature of the refrigerant pipe and the resulting temperature difference as described above In response to the temperature difference, a control command is applied to the valve control unit 230, and the valve control unit 230 controls the closing of the electromagnetic expansion valve 20 step by step. At this time, the pulse value of the electromagnetic expansion valve 20 controlled by the valve control unit 230 is as shown in FIG.

When the indoor unit control unit 210 receives an operation command, the electronic expansion valve opening command according to the load is applied to the valve control unit 230, and the valve control unit 230 controls the opening degree of the electromagnetic expansion valve 20 (S500). . The indoor unit controller 210 starts an indoor unit operation by driving an indoor fan (S510).

As described above, the air conditioner and its operation method according to the present invention have been described with reference to the illustrated drawings. Can be.

1 is a block diagram showing the configuration of an air conditioner according to an embodiment of the present invention,

2 is a view showing the configuration of the indoor unit of FIG.

3 is a block diagram showing a control configuration for the indoor unit of FIG. 2;

4 is an exemplary view showing a change in the opening amount with time of the electronic expansion valve of the indoor unit of FIG.

5 is an exemplary view showing another example of the change in the opening amount with time of the electronic expansion valve of the indoor unit of FIG.

6 is a flowchart illustrating an operation method according to the control of the opening amount of the electromagnetic expansion valve in the indoor unit of the air conditioner according to an embodiment of the present invention.

<Explanation of symbols on main parts of the drawings>

10: indoor heat exchanger 20: electromagnetic expansion valve

50: indoor fan

210: control unit 220: temperature detection unit

230: valve control unit 250: fan control unit

I, I11 to 14, I21, I22: Indoor unit O, O1, O2: Outdoor unit

R, R11 to R14, R21, R22: local controller

Claims (8)

In the air conditioner including a plurality of indoor unit, The indoor unit includes an electronic expansion valve for adjusting the flow rate of the refrigerant; A temperature sensing unit for measuring a refrigerant pipe temperature of the refrigerant suction unit and the refrigerant discharge unit of the indoor heat exchanger; An indoor unit controller configured to calculate a temperature difference between the refrigerant discharge unit and the refrigerant suction unit by using the temperature value measured by the temperature detection unit, and to control the electronic expansion valve in response to the temperature difference; And And a valve control unit configured to control the electromagnetic expansion valve to be closed in stages in response to a control command for the electronic expansion valve of the indoor unit controller. The method of claim 1, The indoor unit control unit applies a control command to the valve control unit such that the electromagnetic expansion valve is in a closed state when the indoor unit is stopped or waiting for operation. And the valve control unit reduces the pulse value of the electromagnetic expansion valve by a unit value so as to correspond to a control command of the indoor unit control unit so as to be in a closed state. The method of claim 1, The indoor unit controller applies a control command to the valve controller to initialize the electronic expansion valve when the indoor unit is initially started. And the valve control unit controls the electromagnetic expansion valve to be in a fully open state, and then controls it to be in a fully closed state in response to a control command according to the initialization. The method of claim 3, wherein The valve control unit when the electronic expansion valve closing control, Even if the electromagnetic expansion valve is closed, the air conditioner by reducing the pulse value by a unit value, further closing control, iteratively performs the closing control step by step until the temperature difference is less than the reference value. Initializing the electronic expansion valve when the indoor unit is initially started; Calculating a temperature difference by measuring a temperature of a refrigerant suction part and a refrigerant discharge part of an indoor heat exchanger while the indoor unit is stopped operating; And Operating the air conditioner including controlling the electronic expansion valve to be in a closed state when the temperature difference is greater than or equal to a reference value. The method of claim 5, After the closing control step of the electromagnetic expansion valve, And regenerating the temperature difference after a predetermined time and repeating the closing control until the regenerated temperature difference is less than the reference value. The method of claim 5, In the initializing step, after the electronic expansion valve is controlled to be in a fully open state, the operation method of the air conditioner for controlling the electromagnetic expansion valve to be in a fully closed state. The method of claim 5, After the initialization step or the closing control step, When the operation command for the indoor unit is input, controlling the opening amount of the electromagnetic expansion valve in response to the load amount according to the indoor unit operation, and driving the indoor unit fan to start the operation of the air conditioner.

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