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: There is provided a system and method for controlling a temperature of a refrigerant in an air conditioner, in which a supercooling degree and/or a superheating degree can be secured by controlling a difference in refrigerant temperatures of a pipe connecting one or more indoor units to one or more outdoor units, and a flow of a specific refrigerant. The system includes: one or more indoor units; one or more outdoor units; a high-pressure pipe and a low-pressure pipe for connecting the indoor units and the outdoor units; and a refrigerant temperature control unit coupled to the high-pressure pipe and the low-pressure pipe, for performing a heat exchange with respect to flowing refrigerants by coupling an inner pipe to an outer pipe, the inner pipe passing through the another pipe.

Abstract: A cogeneration system and a method for controlling the same have an advantage that it is easy to operate a cogeneration device because the operation of the cogeneration device can be controlled according to operation signals of an air conditioner, and have an effect that it is possible to make the best use of the generated electricity of the cogeneration device through an interconnection between the air conditioner and the cogeneration device.

Abstract: A cogeneration system is constructed such that the waste heat recovered from the engine is supplied to the heat pump type air conditioner through the waste heat supplying heat exchanger, thereby maximizing heating capacity and efficiency. A waste heat supplying heat exchanger connecting conduit is formed so as to guide a refrigerant emerging from an indoor unit to enter an outdoor unit through the waste heat supplying heat exchanger, so that the flow path between the waste heat supplying heat exchanger and the heat pump type air conditioner is minimized, thereby reducing installation costs and flow resistance.

Abstract: A cogeneration system has an advantage that a cogeneration section is divided into a main unit and a sub unit, and an engine and a generator are included in the main unit, to thus enable the main unit and the sub unit to be installed at different locations, so that the main unit can be installed on the ground floor or basement of a building to thus minimize building vibrations or noises generated by a load, and the sub unit can be installed near to an air conditioner to thus minimize the length of a refrigerant passage, thereby reducing the installation cost and the flow passage resistance.

Abstract: A cogeneration system is disclosed which includes a generator, a drive source for driving the generator, a waste heat supplying heat exchanger for enhancing the heating performance of a heat pump type air conditioner, an auxiliary heating heat exchanger using the waste heat of the drive source as a heat source for heating indoor air, and a regeneration heat supplying heat exchanger using the waste heat of the drive source as a heat source for regenerating a dehumidifier. The cogeneration system can use the waste heat of the drive source for diverse purposes in accordance with the indoor environment, and can have a maximal efficiency.

Abstract: Method for controlling a multi-type air conditioner having a plurality of indoor units each with an expansion valve, an indoor heat exchanger, and an indoor fan, some of which heat rooms, and rest of which are turned off, including the steps of (S11) defining a saturation temperature of refrigerant by using a heating cycle of the refrigerant, and Mollier chart, (S12) measuring a temperature of the refrigerant stagnant at the turned off indoor units, (S13) determining if a temperature difference of the refrigerant temperature and the saturation temperature is within a temperature range preset at a control part, (S14) opening the expansion valves of the turned off indoor units, if the temperature difference is within the temperature range preset at the control part, and (S15) closing the expansion valve of the turned off indoor units, if the temperature difference is not within the temperature range preset at the control part, whereby minimizing stagnation of refrigerant at turned off indoor units during some o

Abstract: A second-refrigerant pump driving type air conditioner, including an indoor unit having an indoor heat exchanger that circulates a refrigerant containing no oil, a first circulator including a compressor that compresses and discharges a refrigerant containing oil, a first outdoor heat exchanger, a second outdoor heat exchanger, and an outdoor expander, and a second circulator including an intermediate heat exchanger connected to the indoor heat exchanger that circulates the refrigerant containing no oil and heat-exchanges the refrigerant of the first outdoor heat exchanger, a receiver, and a pump. A restriction of a length and a diameter of a connection pipe for connecting an outdoor unit and the indoor unit is decreased, and an oil shortage of the compressor is prevented.

Abstract: An air conditioning system comprises a first tank connected to an outlet side refrigerant line of an indoor unit, a second tank disposed to be lower than the first tank, middle tank installed between the first tank and the second tank, a heat source cycle for depressurizing and cooling the first refrigerant inside the first tank by circulating a second refrigerant and heating the first refrigerant of the second tank, a middle tank cooling unit for feed back connected to an inlet side refrigerant line of the second tank among refrigerant lines of the heat source cycle, a middle tank heating unit for feed back connected to a refrigerant line between the first tank and the second tank among refrigerant lines of the heat source cycle, and a controller for selectively circulating the second refrigerant of the heat source cycle to the middle tank cooling unit for feed back or the middle tank heating unit for feed back.

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: An air conditioning system comprises an indoor unit in which a first refrigerant flows, a first tank connected to an outlet side refrigerant line of the indoor unit for sucking a first refrigerant, a second tank connected to an inlet side refrigerant line of the indoor unit and directly connected to the first tank at a position lower than the first tank for feeding back the first refrigerant stored in the first tank to the indoor unit, a connection line disposed between the first tank and the second tank, a pressure equalizing line disposed between the first tank and the second tank, a heat source cycle for cooling the first refrigerant inside the first tank by circulating a second refrigerant and heating the first refrigerant of the second tank, and a controller for controlling a plurality of switching valves installed at the connection line and the pressure equalizing line.

Abstract: Disclosed herein is a refrigerant filtering apparatus for air conditioners that is capable of filtering refrigerant to remove foreign matter therefrom. The refrigerant filtering apparatus comprises a refrigerant flow channel, a filtering net formed in the shape of a cone and mounted in the refrigerant flow channel, such that the apex part of the filtering net is placed at the upstream side in the refrigerant flow direction while the circumferential part of the filtering net is placed at the downstream side in the refrigerant flow direction, for filtering refrigerant to separate foreign matter therefrom, the filtering net being constructed such that the foreign matter is gathered in the vicinity of the connection between the filtering net and the refrigerant flow channel, and a sludge cup for collecting the foreign matter, the sludge cup being detachably attached to the refrigerant flow channel.

Abstract: A multi-type air conditioner includes an outdoor unit, one or more indoor units communicating with the outdoor unit, and a liquid-stay preventing device heating and evaporating a liquefied refrigerant so as to prevent the liquefied refrigerant circulating between the indoor unit and the outdoor unit from being accumulated at a low pressure side including the indoor unit. Accordingly, a liquefied refrigerant is not accumulated in an indoor unit and a connection pipe, which are a low pressure side where the pressure is relatively low, but smoothly passes therethrough regardless of a height difference between the indoor unit and the outdoor unit. Therefore, the efficiency of the multi-type air conditioner is improved.

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: 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 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: An apparatus for controlling a refrigerant level comprises a first detecting unit installed at a lower side of the inside of a refrigerant tank, for detecting whether a refrigerant stored at a lower side of the inside of the refrigerant is a liquefied refrigerant or a gaseous refrigerant, a second detecting unit installed at an upper side of the inside of the refrigerant tank, for detecting whether a refrigerant stored at an upper side of the inside of the refrigerant tank is a liquefied refrigerant and a gaseous refrigerant, and a control unit controlling intake and discharge of the liquefied refrigerant according to a value measured by the first detecting unit and the second detecting unit.

Abstract: An air-conditioner having a dual-refrigerant cycle includes a primary refrigerant circuit heat-exchanged with outdoor air; a secondary refrigerant circuit heat-exchanged with indoor air to perform either a cooling operation or a heating operation; and a heat exchange unit disposed between the primary refrigerant circuit and the secondary refrigerant circuit to perform heat exchange therebetween, wherein the secondary refrigerant circuit includes a compressor for compressing a refrigerant circulating in the secondary refrigerant circuit. A condensing pressure of the primary refrigerant circuit is lowered during the hating operation and an evaporation pressure of the primary refrigerant circuit is increased to thereby enhance efficiency of the air-conditioner.

Abstract: Multi-type air conditioner including an outdoor unit having a compressor, an outdoor heat exchanger, a flow path control valve for controlling a flow path of the refrigerant from the compressor, and an outdoor unit piping system, a plurality of indoor units each having an indoor expansion device, an indoor heat exchanger, and an indoor piping system, a distributor for selectively distributing the refrigerant from the outdoor unit to the indoor units and returning to the outdoor unit again proper to respective operation modes, and noise preventing means on pipelines respectively connected to the indoor units to cut off refrigerant flow into inoperative indoor units when the air conditioner is in operation, for preventing occurrence of refrigerant flow noise at the inoperative indoor units.

Abstract: Multi-type air conditioner including an outdoor unit having a compressor, an outdoor heat exchanger, a flow path control valve for controlling a flow path of the refrigerant from the compressor, and an outdoor unit piping system, a plurality of indoor units each having an indoor expansion device, an indoor heat exchanger, and an indoor piping system, a distributor for selectively distributing the refrigerant from the outdoor unit to the indoor units and returning to the outdoor unit again proper to respective operation modes, and noise preventing means on pipelines respectively connected to the indoor units to cut off refrigerant flow into inoperative indoor units when the air conditioner is in operation, for preventing occurrence of refrigerant flow noise at the inoperative indoor units.