Patent Description:
A conventional multi type air conditioner includes two or more indoor units. Pipes connected between an outdoor unit and the indoor units are inspected to diagnose the air conditioner.

In this case, it is detected whether the air conditioner has not been normally installed only when a refrigeration cycle is completely constrained, for example when refrigerant fully leaks from the air conditioner or when a service valve is fully turned off. As a result, diagnosis of the air conditioner is restricted.

<CIT> discloses an apparatus for testing an air conditioner.

According to the invention, there is provided an air conditioner as set out in claim <NUM>. In an aspect of one or more embodiments not part of the invention, there is provided a diagnosis control method of an air conditioner that clearly informs a user or an installation engineer of an installation error which may occur during installation of the air conditioner through diagnosis based on test run such that the user or the installation engineer installs the air conditioner and takes follow-up measures with objectivity and accuracy.

In an aspect of one or more embodiments not part of the invention, there is provided a diagnosis control method of an air conditioner which includes receiving a test run command or a self-diagnosis command for diagnosis of the air conditioner, performing a first test run to diagnose an assembly state of the air conditioner, performing a second test run to diagnose pipe connection of the air conditioner and an amount of refrigerant in the air conditioner, and performing determination including diagnosing a state of the air conditioner based on operation results of the first test run and the second test run and displaying the diagnosis result through a display device provided at an indoor unit of the air conditioner.

The performing the first test run may include diagnosing a communication state and a component assembly state of the air conditioner.

The performing the second test run may further include determining, if a difference (Teva_in)-(Teva_in+<NUM>) between an inlet temperature (Teva_in) of an indoor heat exchanger of an indoor unit before a compressor of an outdoor unit is operated and an inlet temperature (Teva_in+<NUM>) of the indoor heat exchanger of the indoor unit after the compressor of the outdoor unit is operated is less than a predetermined reference value, that a pipe connection error has occurred between the outdoor unit and the indoor unit.

The diagnosis control method may further include determining, if the difference (Teva_in)-(Teva_in+<NUM>) between the inlet temperature (Teva_in) of the indoor heat exchanger before the compressor is operated and an inlet temperature (Teva_in+<NUM>) of the indoor heat exchanger after the compressor is operated is equal to or greater than the predetermined reference value and a difference (Teva_out)-(Teva_in) between the inlet temperature (Teva_in) and an outlet temperature (Teva_out) of the indoor heat exchanger is greater than a reference degree of superheat, that the refrigerant shortage error has occurred.

The performing the second test run may further include determining, if a difference (Tair_in)-(Teva_in) between an indoor air temperature (Tair_in) and an inlet temperature (Teva_in) of an indoor heat exchanger is equal to or less than a predetermined reference value (Ka) and a difference (Tair_in)-(Teva_out) between the indoor air temperature (Tair_in) and an outlet temperature (Teva_out) of the indoor heat exchanger is equal to or less than another predetermined reference value (Kb), that the high-pressure clogging error has occurred in an outdoor unit.

Conditions to determine the refrigerant shortage error in the second test run may include a first determination condition to determine, if the inlet temperature (Teva_in) of the indoor heat exchanger is equal to or less than a predetermined reference evaporation temperature (γ), that the refrigerant shortage error has occurred, a second determination condition to determine, if a difference (Teva_mid)-(Teva_in) between a middle temperature (Teva_mid) of the indoor heat exchanger and the inlet temperature (Teva_in) of the indoor heat exchanger is equal to or greater than a predetermined reference degree of evaporator superheat (δ), that the refrigerant shortage error has occurred, and a third determination condition to determine, if a difference (Tdis)-(Tcond) between a discharge temperature (Tdis) of a compressor and an outlet temperature (Tcond) of an outdoor heat exchanger is equal to or greater than a predetermined degree of discharged superheat (ε), that the refrigerant shortage error has occurred.

The diagnosis control method may further include detecting, if an operation time of the compressor exceeds a predetermined time, the indoor air temperature (Tair_in), an outdoor air temperature (Tair_out), the inlet temperature (Teva_in) of the indoor heat exchanger, the middle temperature (Teva_mid) of the indoor heat exchanger, the outlet temperature (Tcond) of the outdoor heat exchanger, and the discharge temperature (Tdis) of the compressor.

The diagnosis control method may further include determining, if at least two of the first, second, and third determination conditions are satisfied, that the refrigerant shortage error has occurred.

The predetermined reference evaporation temperature (γ) of the first determination condition may be a value defined by γ = (Tair_out-<NUM>) x0.01xC1+(Tair_in-<NUM>)x0.01xC2+C3, where Tair_out is an outdoor air temperature, Tair_in is an indoor air temperature, and C1, C2, and C3 are constants.

The diagnosis control method may further include changing an operation frequency of a compressor so as to correspond to the number of indoor units test running during operation of the compressor.

The diagnosis control method may further include displaying progress of the first test run and the second test run through the display device.

The diagnosis control method may further include displaying progress of the first test run and the second test run in percentage.

The diagnosis control method may further include announcing progress and completion time of the first test run and the second test run using a voice.

The diagnosis control method may further include dividing the first test run and the second test run into a plurality of processes and displaying progress of the first test run and the second test run using one of the processes.

The display device may include a plurality of light emitting devices and the diagnosis control method may further include displaying progress of the first test run and the second test run by turning on the light emitting devices.

The diagnosis control method may further include displaying, in a self-diagnosis mode performed by the self-diagnosis command, a message indicating the self-diagnosis result through the display device.

The performing the first test run may include operating an indoor fan provided in an indoor unit of the air conditioner to saturate a temperature detector provided in the indoor unit.

The diagnosis control method may further include preventing a locked state of the air conditioner from being released such that the operation of the air conditioner is restricted in a case in which test run of the air conditioner has not been performed.

The diagnosis control method may further include resuming the test run if an error occurs during test run of the air conditioner and preventing the locked state of the air conditioner from being released such that the use of the air conditioner is restricted if the test run of the air conditioner is not normally completed.

The diagnosis control method may further include releasing a locked state of the air conditioner even when test run of the air conditioner is not normally completed in a self-diagnosis mode performed by the self-diagnosis command.

The diagnosis control method may further include transmitting setting/installation information to a remote server through a network module to store the setting/installation information in a database if a test run mode performed by the test run command or a self-diagnosis mode performed by the self-diagnosis command is completed.

The diagnosis control method may further include providing, if occurrence of an error is detected in the test run mode or the self-diagnosis mode, a method of resolving the error of the air conditioner and component information necessary to resolve the error through a mobile terminal to provide guidelines to resolve the error.

The diagnosis control method may further include allowing a user to have thorough knowledge of the component information necessary to resolve the error though provision of the component information when the error occurs.

In an aspect of one or more embodiments not part of the invention, there is provided a diagnosis control method of an air conditioner including receiving a test run command for diagnosis of the air conditioner, performing a first test run to diagnose an assembly state of the air conditioner, performing a second test run to diagnose pipe connection of the air conditioner and an amount of refrigerant in the air conditioner, diagnosing a state of the air conditioner based on operation results of the first test run and the second test run, and displaying the diagnosis result through a display device provided at an indoor unit of the air conditioner.

In an aspect of one or more embodiments not part of the invention, there is provided a diagnosis control method of an air conditioner including receiving a self-diagnosis command for diagnosis of the air conditioner, performing a first test run to diagnose an assembly state of the air conditioner, performing a second test run to diagnose pipe connection of the air conditioner and an amount of refrigerant in the air conditioner, diagnosing a state of the air conditioner based on operation results of the first test run and the second test run, and displaying the diagnosis result through a display device provided at an indoor unit of the air conditioner.

These and/or other aspects will become apparent and more readily appreciated from the following description of embodiments, taken in conjunction with the accompanying drawings of which:.

<FIG> is a view showing a refrigeration cycle of an air conditioner according to an embodiment. As shown in <FIG>, the air conditioner may include at least one outdoor unit <NUM> and at least one indoor unit <NUM>. A plurality of indoor units <NUM> may be connected to one outdoor unit <NUM>.

The outdoor unit <NUM> includes a compressor <NUM>, a four-way valve <NUM>, an outdoor heat exchanger <NUM>, an electronic expansion valve <NUM>, and an accumulator <NUM>. The four-way valve <NUM> is connected to a discharge side 102a of the compressor <NUM>. The four-way valve <NUM> is controlled such that refrigerant discharged from the compressor <NUM> flows to one side of the outdoor heat exchanger <NUM> during a cooling operation and such that the refrigerant discharged from the compressor <NUM> flows to one side of the indoor unit <NUM> during a heating operation. The other side of the outdoor heat exchanger <NUM> is connected to the indoor unit <NUM>. An outdoor fan 106a is installed adjacent to the outdoor heat exchanger <NUM>. The accumulator <NUM> is disposed between a suction side 102b of the compressor <NUM> and the four-way valve <NUM>. A compressor discharge temperature detector <NUM> is installed on a refrigerant pipe at the discharge side of the compressor <NUM>. An outdoor temperature detector <NUM> to detect outdoor temperature is installed at a portion of the outdoor unit <NUM>. The compressor <NUM> is a variable capacity compressor. An operation frequency of the compressor <NUM> is changed so as to correspond to capabilities required by the indoor unit <NUM>, whereby capacity of the compressor <NUM> is varied.

In <FIG>, a plurality of indoor units <NUM> is shown. Some of the indoor units <NUM> may be stand type indoor units and some of the indoor units <NUM> may be wall-mount type indoor units. Refrigeration cycle structures of the indoor units <NUM> are basically the same. That is, an indoor heat exchanger <NUM> is provided at each indoor unit <NUM>. An indoor fan 152a is installed adjacent to the indoor heat exchanger <NUM>. In addition, indoor heat exchanger temperature detectors <NUM> to detect inlet temperature and middle temperature and outlet temperature of the indoor heat exchanger <NUM> are installed on refrigerant pipes at opposite sides (inlet and outlet) of the indoor heat exchanger <NUM>. Alternatively, only inlet temperature and middle temperature of the indoor heat exchanger <NUM> may be detected or only inlet temperature of the indoor heat exchanger <NUM> may be detected. In addition, an indoor temperature detector <NUM> to detect indoor temperature is installed at a portion of the indoor unit <NUM>.

<FIG> is a view showing a control system of the air conditioner shown in <FIG>. In the outdoor unit <NUM>, the outdoor temperature detector <NUM>, the compressor discharge temperature detector <NUM>, a current detector <NUM>, a storage device <NUM>, a test run progress rate controller <NUM>, a compressor driving controller <NUM>, an outdoor fan controller <NUM>, a four-way valve controller <NUM>, and an electronic expansion valve controller <NUM> are electrically connected to an outdoor unit controller <NUM> in a communicable fashion. In addition, an outdoor unit power supply device <NUM> to supply power to the outdoor unit <NUM> is provided at the outdoor unit <NUM>. The outdoor temperature detector <NUM> and the compressor discharge temperature detector <NUM> were previously described with reference to <FIG>. The current detector <NUM> measures operating current of the outdoor unit <NUM>. The storage device <NUM> stores data (regarding a temperature detection value, a valve opening value, etc.) generated during operation of the air conditioner and software necessary to operate the air conditioner. The test run progress rate controller <NUM> checks a test run progress rate and provides information regarding the test run progress rate to the outdoor unit controller <NUM>. The outdoor unit controller <NUM> transmits the information regarding the run progress rate to the indoor unit <NUM> such that the indoor unit <NUM> displays the progress rate. The compressor driving controller <NUM> controls operation of the compressor <NUM>. The outdoor fan controller <NUM> controls operation (on/off) and rotational speed of the outdoor fan 106a. The four-way valve controller <NUM> controls opening/closing and an opening degree of the four-way valve <NUM>. The electronic expansion valve controller <NUM> controls an opening degree of the electronic expansion valve <NUM> in response to a control command from the outdoor unit controller <NUM>.

In the indoor unit <NUM>, the indoor heat exchanger temperature detectors <NUM>, the indoor temperature detector <NUM>, an input device <NUM>, an indoor fan controller <NUM>, and a display device <NUM> are electrically connected to an indoor unit controller <NUM> in a communicable fashion. In addition, an indoor unit power supply device <NUM> to supply power to the indoor unit <NUM> is provided at the indoor unit <NUM>. The indoor heat exchanger temperature detectors <NUM> and the indoor temperature detector <NUM> were previously described with reference to <FIG>. The input device <NUM> allows a user or an engineer to generate a command to control the air conditioner. The input device <NUM> includes buttons and keys to generate a basic operation control command of the air conditioner. Particularly, the input device <NUM> includes a test run button 254a to generate a test run command. The indoor fan controller <NUM> controls operation (on/off) and rotational speed of the indoor fan 152a. The display device <NUM> displays an operation state of the air conditioner and a message or warning generated during operation of the air conditioner. The display device <NUM> is provided at the indoor unit <NUM>. Particularly, the display device <NUM> displays a test run progress rate and a test run result such that a user (consumer) may directly recognize the test run result. In a case in which the indoor unit <NUM> is of a stand type, the display device <NUM> may be a liquid crystal display (LCD) panel. In a case in which the indoor unit <NUM> is of a wall-mount type, the display device <NUM> may be a light emitting device, such as a light emitting diode (LED) device. In addition, the display device <NUM> may include a speaker. In a case in which the display device <NUM> is an LCD panel, a test run progress state of diagnosis control up to now may be displayed as a percentage or the test run may be divided into <NUM> to <NUM> steps and each progress step may be displayed. In addition, a graph may be displayed or an inspection result may be expressed using a word, such as <normal> or <inspection>. The word <inspection> indicates that the air conditioner is operating abnormally and needs to be inspected. In a case in which the display device <NUM> is an LED device, a plurality of LEDs may be installed such that a test run progress degree is displayed based on the number of lit LEDs. In a case in which the display device <NUM> includes a speaker, a progress degree may be announced using a voice. In addition, a network module <NUM> to transmit and receive data to and from a remote server is included in the indoor unit.

Two-way communication is performed between the outdoor unit <NUM> and the indoor units <NUM> shown in <FIG> and <FIG>. Two-way communication is also performed between the indoor units <NUM>. The outdoor unit <NUM> and the indoor units <NUM> may exchange various kinds of information generated during operation of the air conditioner through such two-way communication.

<FIG> is a view showing a diagnosis control method (test run mode) of an air conditioner according to an embodiment. <FIG> is a view showing a diagnosis control method (self-diagnosis mode) of an air conditioner according to an embodiment. The test run mode of <FIG> may be used as a method of checking whether an air conditioner is normally installed when the air conditioner is installed for the first time or reinstalled after removal of the air conditioner. On the other hand, the self-diagnosis mode may be used as a method of a user (or a service engineer) directly checking whether an installed state of an air conditioner is normal during use of the air conditioner after installation of the air conditioner. Of course, the service engineer may use the self-diagnosis mode and the user may use the test run mode. The diagnosis control method shown in <FIG> and <FIG> is performed under control of the outdoor unit controller <NUM> and the indoor unit controller <NUM> shown in <FIG>.

In the test run mode of <FIG>, when a user (consumer) or an installation engineer manipulates the test run button 254a provided at the input device <NUM> of the indoor unit <NUM> to generate a test run command, the indoor unit controller <NUM> receives the test run command and transmits the test run command to the outdoor unit controller <NUM> (<NUM>). As a result, the indoor unit controller <NUM> and the outdoor unit controller <NUM> jointly recognize that the test run command has been generated.

The diagnosis control method (test run mode) of the air conditioner includes a first test run process <NUM>, a second test run process <NUM>, a first determination process <NUM>, and a second determination process <NUM>. In the first test run process <NUM>, an assembly state and a driving state of various kinds of machinery and equipment and application components in the outdoor unit <NUM> and the indoor unit <NUM> are checked while the indoor fan 152a of the indoor unit <NUM> is operated. In the second test run process <NUM>, it is checked whether refrigerant normally flows between the indoor unit <NUM> and each indoor unit <NUM> while the compressor <NUM> of the outdoor unit <NUM> is operated. In the first determination process <NUM>, it is checked whether a high-pressure clogging error has occurred based on the operation results of the first test run process <NUM> and the second test run process <NUM>. The high-pressure clogging error occurs when a constraint condition, such as valve locking or expansion valve locking, which disturbs refrigerant circulation, is met. In the second determination process <NUM>, it is determined whether a necessary amount of refrigerant is normally supplied to each indoor unit <NUM>. The second determination process <NUM> is a refrigerant shortage determination process to determine whether refrigerant is normally circulated without clogging and then to determine whether the amount of refrigerant supplied to each indoor unit <NUM> is sufficient. The first determination process <NUM> and the second determination process <NUM> may be combined into a single determination process.

The self-diagnosis mode of <FIG>, which is frequently used by a user during use of the air conditioner after the air conditioner is installed, is performed using an entry mode different from the test run mode. In addition, unlike the test run mode, the first determination process is omitted and only the second determination process is performed in the self-diagnosis mode. The self-diagnosis mode is an inspection mode performed by a user during use of the normally installed air conditioner. Based on the self-diagnosis result, <normal> or <inspection> may be displayed through the display device <NUM> of the indoor unit. Unlike the test run mode, switching to a locked state is not performed even when an error occurs. When a user (consumer) or an installation engineer manipulates a self-diagnosis button 254b provided at the input device <NUM> of the indoor unit <NUM> to generate a self-diagnosis command, the indoor unit controller <NUM> receives the self-diagnosis command and transmits the self-diagnosis command to the outdoor unit controller <NUM> (<NUM>). As a result, the indoor unit controller <NUM> and the outdoor unit controller <NUM> jointly recognize that the self-diagnosis command has been generated.

The diagnosis control method (self-diagnosis mode) of the air conditioner includes a first test run process <NUM>, a second test run process <NUM>, and a determination process <NUM>. The first test run process <NUM> and the second test run process <NUM> are performed in the same manner as the first test run process <NUM> and the second test run process <NUM> of the test run mode. That is, in the first test run process <NUM>, an assembly state and a driving state of various kinds of machinery and equipment and application components in the outdoor unit <NUM> and the indoor unit <NUM> are checked while the indoor fan 152a of the indoor unit <NUM> is operated. In the second test run process <NUM>, it is checked whether a high-pressure clogging error has occurred and a refrigerant shortage error has occurred as previously described while the compressor <NUM> of the outdoor unit <NUM> is operated. In the determination process <NUM>, however, it is determined whether a high-pressure clogging error has occurred and then whether a refrigerant shortage error has occurred without division into the first determination process and the second determination process.

<FIG> is a flowchart showing the first test run process of the diagnosis control method shown in <FIG> and <FIG>. As shown in <FIG>, in the first test run process <NUM>, a communication state between the outdoor unit <NUM> and the indoor unit <NUM> is checked and, when checking of the communication state is completed, a component misassembly state is checked while the indoor fan 152a is operated (<NUM>). Checking of the communication state is possible through checking of a response signal generated when the corresponding components are normally operated. Checking of the component misassembly state is also possible through checking of a response generated when the corresponding components are normally assembled. If both the communication state and the component assembly state are normal (YES of <NUM>), the indoor fan 152a is operated to blow air into an air conditioning space in which the indoor unit <NUM> is installed (<NUM>). At this time, the electronic expansion valve of each indoor unit <NUM> is initialized and the four-way valve <NUM> of the outdoor unit <NUM> is closed. The indoor fan 152a is continuously operated until a predetermined time tn1 is reached (NO of <NUM>). If an operation progress time of the indoor fan 152a reaches the predetermined time tn1, entry into the second test run process <NUM> is performed (YES of <NUM>). Here, the indoor fan 152a is operated for the predetermined time tn1 in a state in which the compressor <NUM> is stopped because it is necessary to saturate the temperature detector (that is, the indoor heat exchanger temperature detectors <NUM> and the indoor temperature detector <NUM>) of the indoor unit <NUM> to the temperature of the air conditioning space in order to prevent a determination error in a subsequent process. If both the communication state and the component assembly state are not normal in the process <NUM> of checking the communication state between the outdoor unit <NUM> and the indoor unit <NUM> and the component misassembly state (NO of <NUM>), the procedure advances to <NUM> of the first determination process <NUM>, which will hereinafter be described (see <FIG>).

<FIG> is a flowchart showing the second test run process of the diagnosis control method shown in <FIG> and <FIG>. As shown in <FIG>, in the second test run process <NUM>, an inlet temperature Teva_in of the indoor heat exchanger <NUM> is measured through the indoor heat exchanger temperature detectors <NUM> before the compressor <NUM> is operated and the number of indoor units <NUM> to be test run is checked (<NUM>). The number of indoor units <NUM> to be test run may be checked through communication with the indoor units <NUM> which are operated. It is assumed that the indoor units <NUM> include a stand type indoor unit and a wall-mount type indoor unit. If both the stand type indoor unit and the wall-mount type indoor unit are test running, the number of indoor units <NUM> test running is <NUM>. If only the stand type indoor unit or the wall-mount type indoor unit is currently test running, the number of indoor units <NUM> test running is <NUM>. Subsequently, the electronic expansion valve <NUM> of the indoor unit <NUM> is opened, and the compressor <NUM> is operated at an operation frequency Cf/Cfm corresponding to the number of indoor units <NUM> test running (<NUM>). The operation frequency Cf of the compressor <NUM> is an operation frequency of the compressor <NUM> when only one indoor unit <NUM> is test run. The operation frequency Cfm of the compressor <NUM> is an operation frequency of the compressor <NUM> when a plurality of indoor units <NUM> is test run. During operation of the compressor <NUM>, it is compared whether the number of indoor units <NUM> test running is equal to the number of the indoor units <NUM> having test run (<NUM>). If the number of indoor units <NUM> test running is not equal to the number of the indoor units <NUM> having test run (NO of <NUM>), the operation frequency Cf/Cfm of the compressor <NUM> is changed so as to correspond to the number of indoor units <NUM> test running (<NUM>). That is, if the number of indoor units <NUM> test running is greater than the number of the indoor units <NUM> having test run, the operation frequency Cf/Cfm of the compressor <NUM> is increased. On the other hand, if the number of indoor units <NUM> test running is less than the number of the indoor units <NUM> having test run, the operation frequency Cf/Cfm of the compressor <NUM> is decreased. The reason that the operation frequency of the compressor <NUM> is changed based on a single operation or multiple operations is that the operation frequency of the compressor <NUM> is changed based on the sum of operating capacity required by the indoor units <NUM> to improve reliability in diagnosis result of the air conditioner and discrimination in determination. If the number of indoor units <NUM> test running is equal to the number of the indoor units <NUM> having test run (YES of <NUM>) in the process <NUM> of comparing whether the number of indoor units <NUM> test running is equal to the number of the indoor units <NUM> having test run, the compressor <NUM> is continuously operated without change of the operation frequency Cf/Cfm of the compressor <NUM>. The compressor <NUM> is continuously operated until an operation progress time of the compressor <NUM> reaches a predetermined time tn2 (<NUM>). If the operation progress time of the compressor <NUM> reaches the predetermined time tn2 (YES of <NUM>), entry into the first determination process <NUM> is performed. For reference, the electronic expansion valve <NUM> of the indoor units <NUM> test running remains open at a predetermined fixed opening degree during operation of the compressor <NUM> such that a predetermined amount of refrigerant is supplied to the indoor unit <NUM>. Proper opening values of the electronic expansion valve <NUM> of the indoor units <NUM> test running are prestored in the storage device <NUM> such that proper opening degrees of the electronic expansion valve <NUM> necessary for diagnosis based on model of the air conditioner are maintained.

<FIG> is a flowchart showing an embodiment not part of the invention of the first determination process of the diagnosis control method (test run mode) shown in <FIG>. As previously described with reference to <FIG>, if the operation progress time of the compressor <NUM> reaches the predetermined time tn2 (YES of <NUM>), entry into the first determination process <NUM> is performed. In the first determination process <NUM>, an inlet temperature Teva_in+<NUM> of the indoor heat exchanger of the indoor unit <NUM> test running is detected (<NUM>). Subsequently, a difference (Teva_in)-(Teva_in+<NUM>) between the inlet temperature Teva_in (see <NUM> of <FIG>) of the indoor heat exchanger <NUM> detected before the compressor <NUM> is operated and the current inlet temperature Teva_in+<NUM> (see <NUM>) of the indoor heat exchanger is compared with a predetermined reference value Ta (<NUM>). If (Teva_in)-(Teva_in+<NUM>) is less than the reference value Ta (YES of <NUM>), the operations of the indoor fan 152a and the compressor <NUM> are stopped and the first determination result is displayed as a pipe connection error on the display device <NUM> (<NUM>). (Teva_in)-(Teva_in+<NUM>) being equal to or greater than the reference value Ta indicates that the refrigerant is normally circulated to the indoor units <NUM> test running, which indicates that pipe connection between the outdoor unit <NUM> and the indoor units <NUM> test running is normal. Furthermore, this indicates that a refrigerant constraint condition is not met due to locking of service valve (not shown) or locking of the electronic expansion valve <NUM>. That is, a high-pressure clogging error does not occur. On the other hand, (Teva_in) -(Teva_in+<NUM>) being less than the reference value Ta indicates that refrigerant is not normally circulated due to mispiping between the outdoor unit <NUM> and the indoor unit <NUM>. For reference, even in a case in which both the communication state and the component assembly state are not normal (YES of <NUM>) in the process <NUM> of checking the communication state between the outdoor unit <NUM> and the indoor unit <NUM> and the component misassembly state as previously described with reference to <FIG>, a corresponding error is displayed through the display device <NUM> in the process <NUM> of <FIG>. If (Teva_in)-(Teva_in+<NUM>) is equal to or greater than the reference value Ta (YES of <NUM>), it is determined that a high-pressure clogging error has not occurred and entry into the second determination process <NUM> is performed.

<FIG> is a flowchart showing another embodiment not part of the invention of the first determination process of the diagnosis control method (test run mode) shown in <FIG>. In the first determination process shown in <FIG>, a state in which refrigerant is not circulated to each indoor unit <NUM> due to two conditions, such as clogging of the air conditioner and complete leakage of the refrigerant, is detected. If the compressor <NUM> is continuously operated in a state in which the refrigerant is not circulated in the air conditioner, the compressor <NUM> may be seriously damaged, for example burned out. For this reason, if an operation state corresponding to high-pressure clogging is detected in the test run mode, the operation of the air conditioner is stopped and a corresponding error is displayed. As shown in <FIG>, an indoor air temperature Tair_in is detected (<NUM>). The compressor <NUM> is continuously operated until an operation time of the compressor <NUM> reaches a predetermined compressor operation reference time tn (<NUM>). If the operation time of the compressor <NUM> reaches the compressor operation reference time tn (YES of <NUM>), it is checked whether the compressor frequency Cf is equal to or greater than a compressor target frequency Cf2 (<NUM>). If the compressor frequency Cf is greater than the compressor target frequency Cf2 (YES of <NUM>), an inlet temperature Teva_in and an outlet temperature Teva_out of the indoor heat exchanger are detected (<NUM>). If a difference (Tair_in)-(Teva_in) between the indoor air temperature Tair_in and the inlet temperature Teva_in of the indoor heat exchanger is equal to or less than a predetermined reference value Ka and a difference (Tair_in)-(Teva_out) between the indoor air temperature Tair_in and the outlet temperature Teva_out of the indoor heat exchanger is equal to or less than another predetermined reference value Kb (YES of <NUM>), it is determined that the corresponding electronic expansion valve of the outdoor unit <NUM> is clogged or the refrigerant has completely leaked, the operation of the compressor <NUM> is stopped (<NUM>), and a corresponding error is displayed through the display device <NUM> (<NUM>). On the other hand, if the difference (Tair_in)-(Teva_in) between the indoor air temperature Tair_in and the inlet temperature Teva_in of the indoor heat exchanger is greater than the predetermined reference value Ka and the difference (Tair_in)-(Teva_out) between the indoor air temperature Tair_in and the outlet temperature Teva_out of the indoor heat exchanger is greater than the predetermined reference value Kb (NO of <NUM>), it is determined that high-pressure clogging has not occurred and entry into the second determination process <NUM> to determine an amount of the refrigerant is performed.

<FIG> is a flowchart showing an embodiment not part of the invention of the second determination process of the diagnosis control method shown in <FIG>. The second determination process shown in <FIG> is performed if (Teva_in)-(Teva_in+<NUM>) is equal to or greater than the reference value Ta (NO of <NUM>) in the first determination process <NUM> of <FIG>. First, if (Teva_in)-(Teva_in+<NUM>) is equal to or greater than the reference value Ta and the operation time of the compressor <NUM> is a predetermined time tc (for example, <NUM> minutes) (YES of <NUM>), the inlet temperature Teva_in and the outlet temperature Teva_out of the indoor heat exchanger of the indoor unit <NUM> test running are detected (<NUM>).

If the number of the indoor units <NUM> test running is <NUM> (YES of <NUM>) and a difference (Teva_out)-(Teva_in) between the inlet temperature Teva_in and the outlet temperature Teva_out of the indoor heat exchanger of the corresponding indoor unit <NUM> is less than a reference degree of superheat Tok (YES of <NUM>), the second determination is ended, the operations of the indoor fan 152a and the compressor <NUM> are stopped, and the second determination result is displayed as <normal> on the display device <NUM> (<NUM>).

If the number of the indoor units <NUM> test running is plural (NO of <NUM>) in the process <NUM> and the difference (Teva_out)-(Teva_in) between the inlet temperature Teva_in and the outlet temperature Teva_out of the indoor heat exchanger of each indoor unit <NUM> is less than another reference degree of superheat Tokm (YES of <NUM>), the second determination is ended, the operations of the indoor fan 152a and the compressor <NUM> are stopped, and the second determination result is displayed as <normal> on the display device <NUM> (<NUM>). If the difference (Teva_out)-(Teva_in) between the inlet temperature Teva_in and the outlet temperature Teva_out of the indoor heat exchanger is equal to or greater than the reference degree of superheat Tok or Tokm (NO of <NUM> and <NUM>) in the processes <NUM> and <NUM>, the procedure advances to the process <NUM> of displaying the first determination result in the previously described process <NUM> to display a refrigerant shortage error through the display device <NUM>. If the amount of refrigerant circulated in a refrigeration cycle of the air conditioner is insufficient, a gaseous phase rate of refrigerant passing through the indoor heat exchanger <NUM> is increased due to the characteristics of the indoor heat exchanger <NUM> in which phase transition of the refrigerant is performed from a liquid phase to a gaseous phase with the result that the outlet temperature Teva_out of the indoor heat exchanger is increased. In addition, the flow rate of a liquid refrigerant introduced into the inlet of the indoor heat exchanger <NUM> is decreased with the result that pressure is lowered and temperature is also decreased. Consequently, the inlet temperature Teva_in of the indoor heat exchanger is decreased and the outlet temperature Teva_out of the indoor heat exchanger is increased. As a result, the degree of superheat is greater than a normal level. For this reason, if the difference (Teva_out)-(Teva_in) between the inlet temperature Teva_in and the outlet temperature Teva_out of the indoor heat exchanger is equal to or greater than the reference degree of superheat Tok or Tokm (NO of <NUM> and <NUM>), it is determined that the amount of the refrigerant is insufficient. In a case in which the indoor unit <NUM> is of a wall-mount type, only the degree of superheat Tok is applied.

In addition, in a case in which test run of the air conditioner has not been performed, a locked state of the air conditioner may not be released such that the operation of the air conditioner is restricted. In addition, if an error occurs during test run of the air conditioner, the test run may be resumed. If the test run of the air conditioner is not normally completed, a locked state of the air conditioner may not be released such that the use of the air conditioner is restricted.

<FIG> is a flowchart showing another embodiment not part of the invention of the second determination process of the diagnosis control method (test run mode) shown in <FIG>. The second determination process shown in <FIG> may be applied in a case in which only the inlet temperature and the middle temperature of the indoor heat exchanger <NUM> are detected or only the inlet temperature of the indoor heat exchanger <NUM> is detected. In the second determination process shown in <FIG>, three determination conditions are applied. If two or more of the determination conditions are satisfied, it is determined that the amount of refrigerant is insufficient.

As shown in <FIG>, the compressor <NUM> is operated for a predetermined time tc (for example, <NUM> minutes) or more. If the operation time of the compressor <NUM> reaches tc (YES of <NUM>), the following temperatures are detected (<NUM>):.

If the above temperatures are detected, first, second, and third conditions are determined for first error determination (<NUM>). First, for the first condition determination, it is checked whether the inlet temperature Teva_in of the indoor heat exchanger is equal to or less than a predetermined reference evaporation temperature γ. The reference evaporation temperature γ is a value defined by γ = (Tair_out-<NUM>) x0.01xC1+(Tair_in-<NUM>)x0.01xC2+C3 (C1, C2, and C3 being constants decided based on characteristics of the air conditioner). The first determination condition is used to measure the inlet temperature Teva_in of the indoor heat exchanger to determine whether a refrigerant level is insufficient, uses a principle in which the inlet temperature of the indoor heat exchanger is decreased if the refrigerant is insufficient. After the compressor <NUM> is started, the inlet temperature Teva_in of the indoor heat exchanger is measured. If the inlet temperature Teva_in of the indoor heat exchanger is equal to or less than a predetermined value, it is determined that the amount of the refrigerant is insufficient. The predetermined value is changed based on the indoor air temperature Tair_in and the outdoor air temperature Tair_out.

Subsequently, for the second condition determination, it is determined whether refrigerant is insufficient based on a difference (Teva_mid)-(Teva_in) between the middle temperature Teva_mid of the indoor heat exchanger and the inlet temperature Teva_in of the indoor heat exchanger. That is, it is checked whether the difference (Teva_mid)-(Teva_in) between the middle temperature Teva_mid of the indoor heat exchanger and the inlet temperature Teva_in of the indoor heat exchanger is equal to or greater than a predetermined reference degree of evaporator superheat δ. In the second determination condition, if the difference (Teva_mid)-(Teva_in) between the middle temperature Teva_mid of the indoor heat exchanger and the inlet temperature Teva_in of the indoor heat exchanger is greater than the reference degree of evaporator superheat δ, it is determined that the amount of refrigerant circulated in the indoor unit <NUM> is insufficient. If the amount of refrigerant circulated in the refrigeration cycle of the air conditioner is insufficient, a gaseous phase rate of refrigerant passing through the indoor heat exchanger <NUM> is increased due to the characteristics of the indoor heat exchanger <NUM> in which phase transition of the refrigerant is performed from a liquid phase to a gaseous phase with the result that the outlet temperature Teva_out of the indoor heat exchanger is increased. In addition, the flow rate of a liquid refrigerant introduced into the inlet of the indoor heat exchanger <NUM> is decreased with the result that pressure is lowered and the inlet temperature Teva_in of the indoor heat exchanger is also decreased. Consequently, the inlet temperature Teva_in of the indoor heat exchanger is decreased and the outlet temperature Teva_out of the indoor heat exchanger is increased. As a result, the degree of superheat is greater than a normal level. Even in a case in which the temperature detector is not attached to the outlet but to the middle portion of the indoor heat exchanger <NUM>, the difference between the middle temperature Teva_mid of the indoor heat exchanger and the inlet temperature Teva_in of the indoor heat exchanger is greater than a normal level when the refrigerant level is insufficient. For this reason, it is determined whether the refrigerant level is insufficient using the middle temperature Teva_mid of the indoor heat exchanger instead of the outlet temperature Teva_out of the indoor heat exchanger.

Subsequently, for the third condition determination, it is determined whether a refrigerant level is insufficient based on a difference (Tdis)-(Tcond) between the discharge temperature Tdis of the compressor and the outlet temperature Tcond of the outdoor heat exchanger. That is, it is checked whether the difference (Tdis)-(Tcond) between the discharge temperature Tdis of the compressor and the outlet temperature Tcond of the outdoor heat exchanger is equal to or greater than a predetermined degree of discharged superheat ε. If the compressor is operated in a state in which the refrigerant level is insufficient, the discharge temperature Tdis of the compressor is increased with the result that the difference (Tdis)-(Tcond) between the discharge temperature Tdis of the compressor and the outlet temperature Tcond of the outdoor heat exchanger is greater than a normal level, which is used in the third determination condition.

If it is determined that at least two of the first, second, and third determination conditions are satisfied (YES of <NUM>), the operations of the indoor fan 152a and the compressor <NUM> are stopped and the second determination result is displayed as a refrigerant shortage error on the display device <NUM> (<NUM>). On the other hand, if it is determined that at least two of the first, second, and third determination conditions are not satisfied (NO of <NUM>), it is determined that the refrigerant level is sufficient, the operations of the indoor fan 152a, the outdoor fan 106a, and the compressor <NUM> are stopped, and <normal> is displayed on the display device <NUM> (<NUM>).

In <FIG>, the first determination condition, the second determination condition, and the third determination condition are performed as one process. Alternatively, determination of the first determination condition, the second determination condition, and the third determination condition may be partially omitted or the sequence of the first determination condition, the second determination condition, and the third determination condition may be changed based on the following conditions. For example, in the first condition determination process, if the inlet temperature Teva_in of the indoor heat exchanger is equal to or less than the reference evaporation temperature γ it may be determined that the refrigerant level is insufficient and the third condition determination may be performed. In the first condition determination process, on the other hand, if the inlet temperature Teva_in of the indoor heat exchanger is greater than the reference evaporation temperature γ, the second condition determination may be performed.

In the second condition determination process, if the difference (Teva_mid)-(Teva_in) between the middle temperature Teva_mid of the indoor heat exchanger and the inlet temperature Teva_in of the indoor heat exchanger is equal to or greater than the reference degree of evaporator superheat δ, the third condition determination may be performed. In the second condition determination process, on the other hand, If the difference (Teva_mid)-(Teva_in) between the middle temperature Teva_mid of the indoor heat exchanger and the inlet temperature Teva_in of the indoor heat exchanger is less than the reference degree of evaporator superheat δ it may be determined that the refrigerant level is sufficient, the operations of the indoor fan 152a, the outdoor fan 106a, and the compressor <NUM> may be stopped, and <normal> may be displayed on the display device <NUM> (<NUM>).

In the third condition determination process, if the difference (Tdis)-(Tcond) between the discharge temperature Tdis of the compressor and the outlet temperature Tcond of the outdoor heat exchanger is less than the degree of discharged superheat ε, it may be determined that the refrigerant level is sufficient, the operations of the indoor fan 152a, the outdoor fan 106a, and the compressor <NUM> may be stopped, and <normal> may be displayed on the display device <NUM> (<NUM>). In the third condition determination process, on the other hand, if the difference (Tdis)-(Tcond) between the discharge temperature Tdis of the compressor and the outlet temperature Tcond of the outdoor heat exchanger is equal to or greater than the degree of discharged superheat ε, the operations of the indoor fan 152a and the compressor <NUM> may be stopped and the second determination result may be displayed as a refrigerant shortage error on the display device <NUM> (<NUM>).

As is apparent from the above description, in an aspect of embodiments not part of the invention, a diagnosis control method of an air conditioner may clearly inform a user or an installation engineer of an installation error which may occur during installation of the air conditioner through diagnosis based on test run such that the user or the installation engineer installs the air conditioner and takes follow-up measures with objectivity and accuracy, thereby improving installation quality and completeness during installation of the air conditioner and thus improving customer satisfaction.

In addition, a user or a service engineer may determine whether the amount of refrigerant is sufficient using a self-diagnosis mode after the test run is normally completed during installation of the air conditioner, thereby performing inspection of the air conditioner during use of the air conditioner.

In addition, setting/installation information of the air conditioner may be transmitted to a specific remote server using a network (for example, a Wi-Fi network) through a network module and stored in a database after the test run mode or the self-diagnosis mode is completed, thereby achieving construction of a network between the air conditioner and the server.

In addition, if an error occurs during execution of the test run mode or the self-diagnosis mode, a service engineer may check a serial number (S/N) of the air conditioner using a mobile terminal, such as a smartphone and, correspondingly, the air conditioner may inform the service engineer of a method of resolving a corresponding test run error and information (database code, 3D image, etc.) of a corresponding defective component to provide the service engineer with guidelines to resolve the error and enable the service engineer to order a component to be replaced.

In a case in which a problem is encountered during use of the air conditioner, a user may transmit corresponding operation information of the air conditioner to a server and a mobile terminal of the user. When a service call is made, a service engineer may visit the user after previously having thorough knowledge of an operation state and information of the air conditioner. In a case in which a defective component is to be replaced, therefore, the service engineer may prepare a substitute, thereby preventing additional visit and thus reducing service expenses and improving customer satisfaction.

Claim 1:
An air conditioner comprising:
an indoor unit (<NUM>) including an indoor unit controller (<NUM>), a display (<NUM>), an indoor fan (152a), an indoor heat exchanger (<NUM>), and an indoor heat exchanger temperature detector (<NUM>) configured to detect inlet temperature of the inlet refrigerant pipe of the indoor heat exchanger (<NUM>);
an outdoor unit (<NUM>) connected to the indoor unit (<NUM>) by at least one refrigerant pipe, and including an outdoor unit controller (<NUM>), a compressor (<NUM>) and an outdoor unit power supply device (<NUM>) configured to receive power to be used in the outdoor unit (<NUM>),
wherein the indoor unit (<NUM>) and the outdoor unit (<NUM>) are configured to form a refrigeration cycle;
a storage device (<NUM>) configured to store data generated during operation of the air conditioner and software to operate the air conditioner; and
a controller (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) comprising the outdoor unit controller (<NUM>) and the indoor unit controller (<NUM>) and configured to perform a test run including a first test run and a second test run to diagnose whether the air conditioner is properly installed;
wherein the controller (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) is configured to:
perform the first test run to operate the indoor fan (152a);
perform the second test run to operate the compressor (<NUM>) for a predetermined time, tn2;
determine whether a valve is clogged based on a result of the first test run and a result of the second test run,
wherein the controller (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) is configured to determine that the valve is clogged if a difference between a first inlet temperature (Teva_in) of the indoor heat exchanger (<NUM>) detected by the indoor heat exchanger temperature detector (<NUM>) before the compressor (<NUM>) is operated and a second inlet temperature (Teva_in+<NUM>) of the indoor heat exchanger (<NUM>) detected by the indoor heat exchanger temperature detector (<NUM>) after the compressor (<NUM>) is operated is less than a first reference value, Ta,
if the controller (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) determines that the valve is clogged, the controller (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) is configured to stop operating the compressor (<NUM>) and the indoor fan (152a) and to display an error on the display (<NUM>).