Gas-liquid separator system for refrigeration cycle apparatus

A refrigeration cycle apparatus comprising:

• a main circuit through which refrigerant circulates and in which a compressor, a condenser, a first expansion device, a centrifugal gas-liquid separator that separates refrigerant into gas refrigerant and liquid refrigerant by using centrifugal force, and an evaporator are connected by refrigerant pipes;
• and
• a bypass, including a gas outflow pipe, through which the gas refrigerant obtained through the separation by the gas-liquid separator is returned to a suction side of the compressor,
• wherein the gas-liquid separator includes a cylindrical container, an inflow pipe, the gas outflow pipe, and a liquid outflow pipe,
• wherein the main circuit includes a third expansion device provided between the liquid outflow pipe of the gas-liquid separator and the evaporator, and
• wherein the gas refrigerant discharged from the gas outflow pipe of the gas-liquid separator flows into the bypass, and the bypass includes a second expansion device,
• wherein the first expansion device, the second expansion device, and the third expansion device are controlled such that the liquid refrigerant accumulated in the gas-liquid separator is not discharged from a gas outlet of the gas-liquid separator,
• the refrigeration cycle apparatus further comprising:
• a first temperature sensor that measures a temperature of the refrigerant discharged from a liquid outlet of the gas-liquid separator, a second temperature sensor that measures a temperature of the refrigerant at an outlet of the condenser, and a third temperature sensor that measures an evaporating temperature of the evaporator,
• wherein the first expansion device, the second expansion device, and the third expansion device are controlled based on a frequency of the compressor and results of measurements by the temperature sensors.

A refrigeration cycle apparatus comprising:

• a main circuit through which refrigerant circulates and in which a compressor, a condenser, a first expansion device, a centrifugal gas-liquid separator that separates refrigerant into gas refrigerant and liquid refrigerant by using centrifugal force, and an evaporator are connected by refrigerant pipes;
• and
• a bypass, including a gas outflow pipe, through which the gas refrigerant obtained through the separation by the gas-liquid separator is returned to a suction side of the compressor,
• wherein the gas-liquid separator includes a cylindrical container, an inflow pipe, the gas outflow pipe, and a liquid outflow pipe,
• wherein the main circuit includes a third expansion device provided between the liquid outflow pipe of the gas-liquid separator and the evaporator, and
• wherein the gas refrigerant discharged from the gas outflow pipe of the gas-liquid separator flows into the bypass, and the bypass includes a second expansion device,
• the refrigeration cycle apparatus further comprising an indoor unit including an indoor heat exchanger serving as the condenser, and an outdoor unit including an outdoor heat exchanger serving as the evaporator,
• wherein the indoor unit comprises a plurality of indoor units, and
• wherein the first expansion device, the second expansion device, and the third expansion device are controlled based on a number of indoor units included, a frequency of the compressor, and results of measurements by temperature sensors.