An outdoor unit control unit includes a degree-of-dryness calculating unit that calculates the degree of dryness of a refrigerant flowing into an heat exchanger (an indoor heat exchanger at the time of a cooling operation, and an outdoor heat exchanger at the time of a heating operation) disposed on the downstream side of a liquid pipe, and performs an inhibition mode of inhibiting, when the degree of dryness exceeds a threshold A, control that is performed in the direction of decreasing the degree of opening of the expansion valve (an indoor expansion valve at the time of the cooling operation, and an outdoor expansion valve at the time of the heating operation) disposed on the upstream side of the liquid pipe.

An air treatment system controls airflow volume in accordance with momentarily varying airflow volume to be demanded. A supply fan unit is disposed separately from an air treatment unit, and sends outdoor air from an outdoor space to the air treatment unit and sends outdoor air treated by the air treatment unit to an indoor space. An exhaust fan unit is disposed separately from the air treatment unit, and sends indoor air from the indoor space to the air treatment unit and sends indoor air treated by the air treatment unit to the outdoor space. A controller controls a rotation speed of a first fan in accordance with a first detection value of a first airflow volume detection unit, and controls a rotation speed of a second fan in accordance with a second detection value of a second airflow volume detection unit.

There is provided a refrigerant cycle apparatus capable of suppressing, even when a refrigerant containing CF.sub.3I is used, corrosion of a component of a refrigerant circuit due to the refrigerant containing CF.sub.3I. A refrigerant cycle apparatus includes a refrigerant circuit in which a refrigerant containing CF.sub.3I circulates, the refrigerant circuit including a compressor, an expansion valve, an outdoor heat exchanger, and an indoor heat exchanger that are connected to each other. The refrigerant circuit includes a component to be in contact with the refrigerant. At least a surface of the component to be in contact with the refrigerant is formed by a corrosion resistance material that contains at least one or more selected from a metal in which the percentage of zinc is 10 wt % or less, a resin other than nylon 66, and carbon.

The present invention has an object to provide a refrigeration cycle apparatus. A refrigeration cycle apparatus according to the present invention includes: a compressor; and a control apparatus configured to calculate a rotation number command of the compressor. The control apparatus includes a capacity controller configured to calculate the rotation number of the compressor as a capacity rotation number, a protection controller configured to calculate the rotation number of the compressor as a protection rotation number and a rotation number selection unit configured to select any one of the capacity rotation number and the protection rotation number as the rotation number command of the compressor. The rotation number command of the compressor is calculated so that at least any one of causing the current capacity value to approach the capacity target value and causing the protection variable to approach the protection target value is satisfied.

Systems and methods for controlled subcooling of working fluid in a heating, ventilation, air conditioning and refrigeration (HVACR) system through a suction line heat exchanger are disclosed. The suction line heat exchanger may receive a first fluid flow travelling to a suction of the compressor in the HVACR system and second flow of working fluid that is travelling from a heat exchanger receiving the discharge of the compressor to an expansion device. Superheating of the first working fluid may be determined based on temperature measurements prior to and following the suction line heat exchanger. The superheating may be used to control the quantity of the second flow of working fluid introduced into the suction line heat exchanger, for example to maintain superheat that is below a threshold value. These systems may include chillers and heat pump systems, and methods may be applied to chillers or heat pump systems.

An HVAC system includes a reversing valve configured to receive refrigerant and direct the received refrigerant based on an operating mode of the HVAC system. A sensor measures a heat-exchanger temperature associated with an outdoor heat exchanger. A controller monitors an outdoor temperature and the heat-exchanger temperature and compares these temperatures. The controller determines whether the HVAC system is intended to operate in a cooling or heating mode. If the heat-exchanger temperature is less than the outdoor temperature and the HVAC system is intended to operate in the cooling mode, the controller determines that a first reversing-valve fault is detected. The first reversing-valve fault is associated with the reversing valve being in the heating configuration when the HVAC system is intended to operate in the cooling mode.

The present disclosure provides an air conditioner defrosting control method and device, and a storage medium and an air conditioner. The control method includes: setting a target discharge temperature of a compressor and an initial opening degree of a throttle device when an air conditioner performs defrosting according to an outdoor ambient temperature when the air conditioner meets a defrosting condition and enters a defrosting mode; controlling a defrosting operation of the air conditioner according to the target discharge temperature of the compressor and the initial opening degree of the throttle device; and controlling the air conditioner to exit the defrosting mode when a temperature of an outdoor heart exchanger of the air conditioner reaches a set temperature value.

An air-conditioning system includes a heat source side refrigerant circuit in which a heat source side heat exchanger is provided, a load side heat medium circuit in which a load side heat exchanger is provided, an intermediate heat exchanger, and a heat medium sealing. The heat medium sealing mechanism includes a supply port through which the heat medium and gas flow, the gas being more soluble in the heat medium than air, a discharge port through which the gas pushed by the heat medium is discharged, and a flow straightener that is connected to the load side heat medium circuit in such a manner that, when the gas is supplied, the gas flows from the supply port to the discharge port, and when the heat medium is supplied, the heat medium flows from the supply port to the discharge port.

A defrost cycle control assembly includes a first sensor that is configured to measure a temperature adjacent a top portion of an outdoor heat exchanger of a heat pump, a second sensor that is configured to measure a temperature adjacent a bottom portion of the outdoor heat exchanger, and a third sensor that is configured to measure an ambient temperature. Further, the defrost cycle control assembly includes a controller that is configured to initiate a defrost cycle of the heat pump based on the temperature adjacent the top portion and the ambient temperature when said temperatures indicate formation of frost at the top portion of the outdoor heat exchanger where the first sensor is disposed. The controller is configured to terminate the defrost cycle when the temperature at the bottom portion reaches a termination temperature which indicates that the frost on the outdoor heat exchanger has melted.

According to one embodiment, it preferentially executes, if the starting conditions for defrosting of each air conditioner are met chronologically close to each other, the defrosting operation with respect to the air conditioner starting condition for defrosting of which is earliest among the air conditioners without waiting for a time when the starting condition for defrosting thereof is met.