Abstract: Disclosed are a method and a device for controlling refrigerant in an air conditioning system. The method includes: S1: comparing a superheat degree of each outdoor unit with an average superheat degree; S2: if the superheat degree of a present outdoor unit is higher than the average superheat degree, and a first different between the superheat degree of the present outdoor unit and the average superheat degree is greater than a present value, increasing a refrigerant amount entered into the present outdoor unit; and S3: if the superheat degree of the present outdoor unit is lower than the average superheat degree, and a second different between the average superheat degree and the superheat degree of the present outdoor unit is greater than the present value, decreasing the refrigerant amount entered into the present outdoor unit. Therefore, the refrigerant amount entered into each outdoor unit is adjusted from systemic overall perspective.

Abstract: A method and device for defrosting an air conditioner. The method comprises the following steps: detecting a refrigerant pressure of a heat exchange; obtaining, according to the detected refrigerant pressure of the heat exchange, a corresponding saturation temperature; obtaining an ambient dew point temperature; and when the corresponding saturation temperature is less than 0° C. and less than the ambient dew point temperature, controlling the air conditioner to enter a defrost mode. The method can ensure timely defrosting when frost is formed, prevent defrosting when no frost is formed, extending a service life of an air conditioner.

Abstract: The present disclosure provides an air conditioner system and a control method for the same. The air conditioner system includes: a refrigeration system. A first port of a second four-way valve is connected to a pipeline between the first four-way valve and the indoor heat exchanger, and a second port of a second four-way valve is connected to a first position in a pipeline between the indoor heat exchanger and the outdoor heat exchanger. A first port of the first passage of an auxiliary heat exchanger is in communication with a fourth port of the second four-way valve, and a second port of the first passage is connected to a second position in a pipeline between the indoor heat exchanger and the outdoor heat exchanger.

Abstract: The present disclosure provides a method for controlling a fresh air machine. The method for controlling the fresh air machine of an air-conditioner includes: determining whether a fault occurs in a return air temperature sensor of the fresh air machine when the fresh air machine operates normally; closing an internal valve corresponding to the fresh air machine and keeping a fan motor operating, when the fault occurs in the return air temperature sensor; determining whether a fault occurs in an delivery air temperature sensor of the fresh air machine; when the fault does not occur in the delivery air temperature sensor of the fresh air machine, obtaining an delivery air temperature of the fresh air machine and controlling the fresh air machine to operate again by using the obtained delivery air temperature as a new return air temperature. The present disclosure also provides a fresh air machine.

Abstract: It is provided a cold-air-avoidance control method and apparatus of an indoor unit of a multi-split air conditioning system, the multi-split air conditioning system includes an outdoor unit and a plurality of indoor units, and the cold-air-avoidance control method includes: obtaining a saturation temperature corresponding to a high pressure of the outdoor unit; obtaining an entrance temperature and a return air temperature of a heat exchanger of each heating indoor unit, and controlling an operating status of the heating indoor unit according to the saturation temperature, the entrance temperature and the return air temperature. With the method according to the present disclosure, reliability and accuracy of controlling the heating indoor unit can be improved, such that the effect of the cold-air-avoidance control is improved, and a more comfortable heating process is provided.

Abstract: In an air conditioning system of the present disclosure, the controlling module determines state of the indoor unit. If the indoor unit is under off state, the controlling module determines whether an indoor temperature is smaller than a preset temperature. If yes, the controlling module controls the indoor unit to heat according to a first heating temperature. If the indoor unit is under heating state, the controlling module sets a second heating temperature of the indoor unit to the first heating temperature, and controls the indoor unit to heat according to the first heating temperature. The first heating temperature is smaller than the second heating temperature. If the indoor unit is under cooling state, the controlling module sets a first cooling temperature to a second cooling temperature which is greater than the first cooling temperature, and controls the indoor unit to cool according to the second cooling temperature.

Abstract: Disclosed are a method and a device for controlling refrigerant in an air conditioning system. The method includes: S1: comparing a superheat degree of each outdoor unit with an average superheat degree; S2: if the superheat degree of a present outdoor unit is higher than the average superheat degree, and a first different between the superheat degree of the present outdoor unit and the average superheat degree is greater than a present value, increasing a refrigerant amount entered into the present outdoor unit; and S3: if the superheat degree of the present outdoor unit is lower than the average superheat degree, and a second different between the average superheat degree and the superheat degree of the present outdoor unit is greater than the present value, decreasing the refrigerant amount entered into the present outdoor unit. Therefore, the refrigerant amount entered into each outdoor unit is adjusted from systemic overall perspective.

Abstract: A back-up power source apparatus in an indoor unit of a multi-split air conditioning system includes first and second voltage detecting circuits and a control circuit connected with the first and second voltage detecting circuits. The first and second voltage detecting circuits detect voltages of first and second power sources on a mainboard of the indoor unit in real time respectively, and the control circuit controls the back-up power source apparatus to enter a corresponding operation state according to the voltages of the first and/or second power sources. A controlling method of the back-up power source apparatus and a multi-split air conditioning system including the back-up power source apparatus are also provided.

Abstract: An outdoor unit of an air-conditioner and two-pipe and three-pipe air-conditioning systems having the same are provided. The outdoor unit includes a compressor defining an outlet and an inlet; a first four-way valve defining a first valve communicated with the outlet, second and third ports communicated with the inlet; a second four-way valve defining second and third ports communicated with the inlet; an outdoor heat exchanger defining a first refrigerant valve Communicated with the fourth port of the first four-way valve; a first gas pipe defining a first end connected with the second and third ports of the first and second four-way valves and, the inlet; a second gas pipe defining a first end connected with the fourth port of the second four-way valve; a third gas pipe defining a first end connected with the outlet and a second end connected with the first port of the second four-way valve.

Abstract: A controlling method of a multi-unit air conditioning system in the present disclosure includes: S1: sending a first selection signal, or a second selection signal; S2: controlling the multi-unit air conditioning system to operate under a first control mode according to the first selection signal; S3: controlling the multi-unit air conditioning system to operate under a second control mode according to the second selection signal; S4: receiving a mode-on signal; S5: determining whether a second operating mode is the same as the first operating mode, if no, entering step S6; S6: turning on an indoor-unit fan of the first indoor unit and sending a mode conversion signal to the outdoor-unit controller; S8: converting an operating mode of the outdoor unit; S9: controlling the first indoor unit to operate under the first operating mode; S10: controlling operation of the second indoor unit according to the parameters of the first operating mode.

Abstract: In an air conditioning system of the present disclosure, the controlling module determines state of the indoor unit. If the indoor unit is under off state, the controlling module determines whether an indoor temperature is smaller than a preset temperature. If yes, the controlling module controls the indoor unit to heat according to a first heating temperature. If the indoor unit is under heating state, the controlling module sets a second heating temperature of the indoor unit to the first heating temperature, and controls the indoor unit to heat according to the first heating temperature. The first heating temperature is smaller than the second heating temperature. If the indoor unit is under cooling state, the controlling module sets a first cooling temperature to a second cooling temperature which is greater than the first cooling temperature, and controls the indoor unit to cool according to the second cooling temperature.

Abstract: An outdoor unit of an air-conditioner and two-pipe and three-pipe air-conditioning systems having the same are provided. The outdoor unit includes a compressor defining an outlet and an inlet; a first four-way valve defining a first valve communicated with the outlet, second and third ports communicated with the inlet; a second four-way valve defining second and third ports communicated with the inlet; an outdoor heat exchanger defining a first refrigerant valve Communicated with the fourth port of the first four-way valve; a first gas pipe defining a first end connected with the second and third ports of the first and second four-way valves and, the inlet; a second gas pipe defining a first end connected with the fourth port of the second four-way valve; a third gas pipe defining a first end connected with the outlet and a second end connected with the first port of the second four-way valve.