An air-conditioning apparatus is capable of cooling a first heat medium and heating the first heat medium at the same time in a relay unit, and the cooled first heat medium and the heated first heat medium can be separately distributed to a plurality of indoor units. Waste heat of a first refrigerant circuit can be discharged to an outdoor space via a second heat medium and the second refrigerant.

Task: To provide a high quality air conditioner with high efficiency and stability, preventing adverse effect of manufacturing variation on the refrigerant distribution. Solution: The air conditioner having an expansion valve for decompressing a refrigerant, and a heat exchanger for heat exchange between the refrigerant and air. The air conditioner includes a first linearly shaped piping that is connected to the expansion valve and vertically disposed, a branch pipe connected to the first piping for branching a refrigerant flow path into a plurality of sections, a plurality of second pipings connected to the branch pipe, and a plurality of distributors connected to the second piping for further branching the refrigerant flow path to the heat exchanger.

An air-conditioning apparatus includes actuation control means including an actuation unit that sequentially opens heat medium flow switching devices or heat medium flow control devices on a one-by-one basis. The actuation control means performs control in such a manner that start time of driving of pumps is later than start of actuation of the heat medium flow switching devices and the heat medium flow control devices.

An operation control apparatus of air-conditioning apparatus having an outdoor unit and an indoor unit includes a controller programmed to execute energy conservation control of the air conditioning apparatus. The controller includes at least one required temperature calculation part calculating a required evaporation temperature or a required condensation temperature based on either a current amount of heat exchanged in a usage-side heat exchanger of the indoor unit and a greater amount of heat exchanged in the usage-side heat exchanger than the current amount, or an operating state amount that yields the current amount of heat exchanged in the usage-side heat exchanger and an operating state amount that yields the greater amount of heat exchanged in the usage-side heat exchanger than the current amount.

An air conditioner and a method of controlling an air conditioner are provided. The method of controlling an air conditioner may include determining whether a low-load condition is satisfied on the basis of a number of indoor devices or a temperature of external air, performing a low-load operation of a compressor at a predetermined frequency when the low-load condition is satisfied, detecting whether an operation pressure is out of a target pressure value or range while the low-load operation is performed, and bypassing a refrigerant from the compressor to a gas/liquid separator via an injection passage when the operation pressure is out of the target pressure value or range.

To provide an air-conditioning apparatus that is safer and has small conveying power for such as water at the indoor unit side can be made small. It is characterized in that a compressor 10 and a heat source side heat exchanger 12 are accommodated in a heat source apparatus 1, an intermediate heat exchanger 15 and a pump 21 in a relay unit 3, a use side heat exchanger 26 in an indoor unit 2, respectively, and when a controller 60 makes the compressor 10 stop based on the thermo-off due to decrease in the heat load in the use side heat exchanger 26 or an operation stop instruction, the controller 60 makes the pump 21 stop after the compressor 10 is stopped or almost at the same time as the stop.

An air conditioner and a method of operating an air conditioner are provided. The air conditioner may include a heat pump having a water-refrigerant heat exchanger that condenses or evaporates a refrigerant by heat exchange with heat source water; a heat source water flow path connected to the water-refrigerant heat exchanger; a pump installed on the heat source water flow path; a variable flow valve installed on the heat source water flow path; and a variable flow valve controller that controls an opening degree of the variable flow valve. The variable flow valve controller may include a heat source water minimum flow manipulator that manipulates a minimum flow rate of the heat source water and regulates the opening degree of the variable flow valve according to the manipulation of the heat source water minimum flow manipulator. Accordingly, a user or installation personnel may selectively regulate power consumption and efficiency as desired.

An air conditioning and heat pump system includes a multi-communicative valve unit, a compressor unit connected to the multi-communicative valve unit, an evaporator unit connected to the multi-communicative valve unit, a heat exchanger connected to multi-communicative valve unit, a water heater connected to the compressor unit and the multi-communicative valve unit, and an evaporative cooling system which comprises at least one multiple-effect evaporative condenser for effectively cooling the working fluid. The air conditioning and heat pump system is selectively operated in one of an air conditioning mode, a heat pump mode, a water heater mode, and a defrosting mode, and can be switched such that the working fluid can either be cooled by the evaporator unit or and evaporative cooling system.

A packaged terminal air conditioner unit is provided. The packaged terminal air conditioner unit includes a casing. A compressor, an interior coil, an exterior coil and a reversing valve are positioned within the casing. The reversing valve is configured for selectively reversing a flow direction of compressed refrigerant from the compressor. The packaged terminal air conditioner also includes at least one phase separator and at least one ejector.

A humidity regulating system comprises: a plurality of humidity adjusting devices to adsorb or vaporize the mist and water of the humidity adjusting rooms, a water regulating device to regulate the water supply to the humidity adjusting devices, a main controlling device to control the humidity regulating system, a communication connecting device to connect the plurality of humidity adjusting devices with the water regulating device and the main controlling device, and a remote controlling device which includes a remote controlling means to communicate with the main controlling device so as to regulate the plurality of humidity adjusting devices to adjust the humidity of the rooms.