Abstract: A method for detecting a clogged state of a pipe of a heat pump type multi-air conditioner includes: detecting a temperature of a pipe of an arbitrary indoor heat exchanger among a plurality of indoor heat exchangers; detecting a pressure of a refrigerant sucked into an arbitrary outdoor unit among a plurality of outdoor units in case of performing an air-conditioning operation, and detecting a pressure of a refrigerant introduced into the arbitrary indoor heat exchanger after being discharged from an arbitrary outdoor unit among the plurality of outdoor units in case of performing a heating operation; and comparing a pressure corresponding to the detected temperature of the pipe and the detected pressure of the refrigerant and determining whether the pipe is clogged based on the comparison result. By detecting a clogged state of a pipe, the heat pump type multi-air conditioner is prevented from being damaged due to a clogged state of the pipe.

Abstract: A system for detecting a mis-connected state between communication lines for a multi-type air conditioner and a method thereof. The system comprises an indoor unit pipe temperature detection unit for detecting a temperature of an indoor unit pipe, and a microprocessor for controlling an opening of an electronic expansion valve based on a temperature detected by the indoor unit pipe temperature detection unit, comparing a temperature response characteristic of the indoor unit pipe with a preset temperature response characteristic of a normal indoor unit pipe based on an opening of the electronic expansion valve, and thereby judging whether the communication lines are mis-connected to one another or not. An indoor unit from which the mis-connection has been generated is fast detected, and error information is displayed. Accordingly, the mis-connected state between the communication lines is restored, thereby preventing a damage of the system due to the mis-connection.

Abstract: Multi-type air conditioner including a plurality of compressors, a plurality of temperature sensors mounted in the plurality of compressors for sensing temperatures in the compressors respectively, and an equalizing pipe in communication with the plurality of compressors, for uniform distribution of oil among the plurality of compressors according to the temperatures sensed at the plurality of temperature sensors respectively, thereby distributing oil among the compressors uniformly at an exact time point at which the oil is distributed among the compressors non-uniformly, not only to permit improvement of the performance of the compressors, but also to permit improvement performance of the air conditioner having the compressors.

Abstract: Disclosed herein is an oil separator for air conditioners that is capable of separating oil from refrigerant. The oil separator comprises a shell having a cylindrical space defined therein, a refrigerant introduction pipe for introducing refrigerant into the shell, a refrigerant discharge pipe for discharging the refrigerant out of the shell, and oil-drop growth accelerating member for accelerating growth of oil drops contained in the refrigerant flowing in the shell.

Abstract: An air conditioning system and an apparatus for protecting the same. The air conditioning system comprise an outdoor unit, a plurality of indoor units connected to the outdoor unit by each refrigerant line, and a refrigerant line closing unit installed at the refrigerant line of the indoor unit for preventing a refrigerant flowing on the refrigerant line of the indoor unit from being introduced into the outdoor unit when power supply to one or more indoor units is cut off.

Abstract: Disclosed are an abnormal state detecting apparatus of a multi-type air conditioner and a method thereof. The method comprises: a user's selecting a test operation, and then detecting plural indoor temperatures of indoor zones where a plurality of indoor units are installed and plural outdoor temperatures of outdoor zones where a plurality of outdoor units are installed; selecting a corresponding test operation mode among a plurality of test operation modes preset according to an average indoor temperature of the detected plural indoor temperatures and an average outdoor temperature of the detected plural outdoor temperatures; test-operating the multi-type air conditioner according to the selected test operation mode, and collecting data showing an operation state of the test-operated air conditioner; and comparing the collected data with a preset reference data and judging an abnormal state of the multi-type air conditioner based on the comparison result.

Abstract: Provided is an air conditioner, particularly, an apparatus and method for controlling a super-heating degree in a heat pump system for preventing a liquid refrigerant from flowing into a compressor. The method includes: operating the heat pump system; receiving a present outdoor temperature, a pipe absorption temperature and a low pressure value of a compressor, respectively; computing a present absorption super-heating degree from a difference between the absorption temperature of the compressor and a saturated temperature at a low pressure side; and comparing an targeted absorption super-heating degree set in advance, with the computed present absorption super-heating degree according to the received outdoor temperature, and controlling the system so that the present absorption super-heating degree may follow the targeted absorption super-heating degree.

Abstract: Disclosed is an apparatus and method for preventing liquid refrigerant accumulation in an accumulator of an outdoor unit of an air conditioner. The method includes the steps of: determining a state of a compressor; if the compressor is in standby mode or off state, turning on a four-way valve; determining whether the state of the compressor in standby mode or off state continues longer than a predetermined amount of time; and if the state of the compressor continues longer than the predetermined amount of time, closing an expansion valve. Particularly, high-pressure refrigerant flows in the closed expansion valve while low-pressure refrigerant flows in a check valve through the four-way valve.

Abstract: Disclosed is a method for controlling an air conditioner. In particular, driving modes of elements, namely sucking/discharge compressure, of the compressor in operation are determined so that variable means are controlled to ensure for the elements of the compressor to be within predetermined value ranges in safe area. According to the present invention, vibrations/noises that usually occur when the compressor is in unstable area are greatly reduced and thus, the compressor can be protected from damages.

Abstract: The present invention relates to a method for controlling an air conditioner, in which operation time periods of an outdoor unit is integrated, to determined a time point when an oil recovery operation is performed, and performing the oil recovery operation only when a summed rates, or a number of indoor units accessed with communication is higher than a value preset at a control unit.

Abstract: A system for controlling an air conditioner includes a plurality of outdoor units each having at least one compressor and an outdoor heat exchanger, an indoor unit connected to the outdoor units by a refrigerant tube, the indoor unit having an indoor heat exchanger, and a pressure regulating tube for equalizing pressure according to an operation mode. The pressure regulating tube is connected between the outdoor units.

Abstract: Disclosed herein are an oil separator and a cooling-cycle apparatus using the oil separator. To a casing of the separator is connected an inflow tube to supply gaseous refrigerant and oil into the casing for allowing them flowing in a swirl pattern, thereby being separated from each other in a cyclone separation manner. Such a separation manner results in an improved oil separation efficiency.

Abstract: A multi-air conditioner comprising: a plurality of indoor units for exchanging the heat with indoor air; a plurality of outdoor units, each outdoor unit having an outdoor heat exchanger for exchanging the heat and a compressor for compressing a fluid; a connecting pipe for connecting the indoor units with the outdoor units; and a pressure equalizing pipe for communicating the outdoor heat exchanger of one outdoor unit with the compressor of at least one other outdoor unit, so that the multi-air conditioner is capable of improving stability, reliability and efficiency of a system by equalizing the low pressure between the indoor units in heating and equalizing the high pressure between the outdoor units in cooling.

Abstract: Disclosed herein is a control method for a multiple heat pump. In the control method, when one of multiple indoor units operates in the heating mode and the other indoor units shut down, electronic expansion valves of the shutdown indoor units are controlled to have an opening degree higher than a standard opening degree if an outlet temperature of compressors is higher than a preset temperature, so as to permit a liquid refrigerant, remaining in the shutdown indoor units, to be more readily recovered to the compressors. This eliminates a refrigerant shortage phenomenon of the compressors and prevents deterioration of heating performance as well as reduction of life-span of the compressors.

Abstract: Disclosed herein is a control method for four-way valves of a multiple heat pump. In the control method, if even at least one of four-way valves of respective outdoor units is not switched to a desired mode upon switching of all of the four-way valves to the desired mode, the other four-way valves, switched to the desired mode, is switched to an opposite direction of the desired mode, and then all of the four-way valves are switched again to the desired mode, thereby simply and rapidly correcting switching error of the four-way valves, resulting in normal operation of the multiple heat pump.

Abstract: Disclosed herein are an oil separator and a cooling-cycle apparatus using the oil separator. To a casing of the separator is connected an inflow tube to supply gaseous refrigerant and oil into the casing for allowing them flowing in a swirl pattern, thereby being separated from each other in a cyclone separation manner. Such a separation manner results in an improved oil separation efficiency.

Abstract: A method for detecting a clogged state of a pipe of a heat pump type multi-air conditioner includes: detecting a temperature of a pipe of an arbitrary indoor heat exchanger among a plurality of indoor heat exchangers; detecting a pressure of a refrigerant sucked into an arbitrary outdoor unit among a plurality of outdoor units in case of performing an air-conditioning operation, and detecting a pressure of a refrigerant introduced into the arbitrary indoor heat exchanger after being discharged from an arbitrary outdoor unit among the plurality of outdoor units in case of performing a heating operation; and comparing a pressure corresponding to the detected temperature of the pipe and the detected pressure of the refrigerant and determining whether the pipe is clogged based on the comparison result. By detecting a clogged state of a pipe, the heat pump type multi-air conditioner is prevented from being damaged due to a clogged state of the pipe.

Abstract: A system for detecting a mis-connected state between communication lines for a multi-type air conditioner and a method thereof. The system comprises an indoor unit pipe temperature detection unit for detecting a temperature of an indoor unit pipe, and a microprocessor for controlling an opening of an electronic expansion valve based on a temperature detected by the indoor unit pipe temperature detection unit, comparing a temperature response characteristic of the indoor unit pipe with a preset temperature response characteristic of a normal indoor unit pipe based on an opening of the electronic expansion valve, and thereby judging whether the communication lines are mis-connected to one another or not. An indoor unit from which the mis-connection has been generated is fast detected, and error information is displayed. Accordingly, the mis-connected state between the communication lines is restored, thereby preventing a damage of the system due to the mis-connection.

Abstract: Disclosed are an abnormal state detecting apparatus of a multi-type air conditioner and a method thereof. The method comprises: a user's selecting a test operation, and then detecting plural indoor temperatures of indoor zones where a plurality of indoor units are installed and plural outdoor temperatures of outdoor zones where a plurality of outdoor units are installed; selecting a corresponding test operation mode among a plurality of test operation modes preset according to an average indoor temperature of the detected plural indoor temperatures and an average outdoor temperature of the detected plural outdoor temperatures; test-operating the multi-type air conditioner according to the selected test operation mode, and collecting data showing an operation state of the test-operated air conditioner; and comparing the collected data with a preset reference data and judging an abnormal state of the air conditioner based on the comparison result.

Abstract: A multi-air conditioner comprising: a plurality of indoor units for exchanging the heat with indoor air; a plurality of outdoor units, each outdoor unit having an outdoor heat exchanger for exchanging the heat and a compressor for compressing a fluid; a connecting pipe for connecting the indoor units with the outdoor units; and a pressure equalizing pipe for communicating the outdoor heat exchanger of one outdoor unit with the compressor of at least one other outdoor unit, so that the multi-air conditioner is capable of improving stability, reliability and efficiency of a system by equalizing the low pressure between the indoor units in heating and equalizing the high pressure between the outdoor units in cooling.