Abstract: An air conditioner (10) composed of a refrigerating apparatus includes a controller (90). A heating control section (91) of the controller (90) feeds electric current in an open phase state to an electric motor (62) of a compressor (30) to heat the compressor (30) in operation stop of the air conditioner (10). The heating control section (91) monitors the detection value of an outdoor air temperature sensor (72) during the operation stop of the air conditioner (10) and keeps on stopping feeding the electric current to the electric motor (62) during the time when the detection value decreases.

Abstract: A compressor capacity control operation mechanism includes a pilot valve (flow channel switching valve) having capillary tubes, a suction branching pipe, an intermediate pipe, and a discharge branching pipe. The suction branching pipe is connected to a first capillary tube and branches off from a compressor suction pipe. The intermediate pipe is connected to a second capillary tube and a compressor cylinder intermediate part. The discharge branching pipe is connected to a third capillary tube and branches off from a compressor discharge pipe. Preferably, the suction, intermediate and discharge branching pipes have larger diameters than the first second and third capillary tubes. Also, the pilot valve preferably has a flow channel configuration switchable between first and second states in which the first, second and third capillary tubes are connected differently in the first and second states.

Abstract: An air conditioner has a heat source unit with a compressor and a heat source heat exchanger and utilization units with utilization expansion valves and utilization heat exchangers. The heat source unit and the utilization unit are interconnected via refrigerant communication pipes. The air conditioner is capable of switching and operating between a normal operation mode in which control of the respective devices is performed depending on the operation loads of the utilization units and a refrigerant quantity judging operation mode in which the utilization units perform cooling operation. The utilization expansion valves are controlled such that degrees of superheating at outlets of the utilization heat exchangers become a positive value, and an operation capacity of the compressor is controlled such that evaporation pressures in the utilization heat exchangers become constant.

Abstract: This invention makes it possible to charge a refrigeration apparatus with the amount of refrigerant that the refrigeration apparatus requires at the time of onsite installation. As a result, the optimum refrigerant charging amount can always be obtained. The refrigeration apparatus is provided with a refrigeration cycle in which an outdoor unit equipped with a compressor, a condenser, and a receiver is connected to an indoor unit equipped with an expansion valve and an evaporator via a liquid pipe and a gas pipe. The refrigeration cycle is charged with refrigerant while a refrigerant charging operation state is created in which the liquid pipe that connects the outdoor unit to the indoor unit is filled with liquid refrigerant having a prescribed density. Refrigerant charging ends when, during the refrigerant charging operation, it is detected that the level of the liquid inside the receiver has reached a prescribed level.

Abstract: Indoor circuits (60, 65) of indoor units (12, 13) are each connected in parallel to an outdoor circuit (20) of an outdoor unit (11). The outdoor circuit (20) has a gas vent pipe (35) by which a receiver (23) is brought into communication with suction sides of compressors (41, 42). During the heating operation in the heating mode of operation, a gas vent solenoid valve (36) is placed in the open state so that the receiver (23) decreases in pressure. This relaxes restrictions on the difference in installation height between each indoor unit of a multi type airconditioner having a plurality of indoor units.

Abstract: Indoor circuits (60, 65) of indoor units (12, 13) are each connected in parallel to an outdoor circuit (20) of an outdoor unit (11). The outdoor circuit (20) has a gas vent pipe (35) by which a receiver (23) is brought into communication with suction sides of compressors (41, 42). During the heating operation in the heating mode of operation, a gas vent solenoid valve (36) is placed in the open state so that the receiver (23) decreases in pressure. This relaxes restrictions on the difference in installation height between each indoor unit of a multi type airconditioner having a plurality of indoor units.

Abstract: A refrigerant circuit (15) is disposed which is formed by connection of an outdoor unit (11) and two indoor units (12, 13). And, the air conditioning capacity of the outdoor unit (11) is controlled such that the temperature of refrigerant circulating through the refrigerant circuit (15) becomes a target value and the target value is altered correspondingly to the state of an operation. In other words, the control characteristics of the target value are determined correspondingly to the air conditioning load characteristics of a building, and the target value is altered according to the control characteristics and based on the inside/outside temperature difference between an indoor set temperature and an outside air temperature.

Abstract: This invention makes it possible to charge a refrigeration apparatus with the amount of refrigerant that the refrigeration apparatus requires at the time of onsite installation. As a result, the optimum refrigerant charging amount can always be obtained. The refrigeration apparatus is provided with a refrigeration cycle (A) in which an outdoor unit (X) equipped with a compressor (1), a condenser (2), and a receiver (3) and an indoor unit (Y) equipped with an expansion valve (4) and an evaporator (5) are connected together by a liquid pipe (8) and a gas pipe (9). The refrigeration cycle (A) is charged with refrigerant while a refrigerant charging operation state is created in which the liquid pipe (8) connecting the outdoor unit (X) to the indoor unit (Y) is filled with liquid refrigerant having a prescribed density.

Abstract: A refrigerant circuit (15) is disposed which is formed by connection of an outdoor unit (11) and two indoor units (12, 13). And, the air conditioning capacity of the outdoor unit (11) is controlled such that the temperature of refrigerant circulating through the refrigerant circuit (15) becomes a target value and the target value is altered correspondingly to the state of an operation. In other words, the control characteristics of the target value are determined correspondingly to the air conditioning load characteristics of a building, and the target value is altered according to the control characteristics and based on the inside/outside temperature difference between an indoor set temperature and an outside air temperature.