Refrigerant cycle apparatus

A refrigerant cycle apparatus that circulates a flammable refrigerant in a refrigerant circuit, the refrigerant cycle apparatus comprising:

• a gas-side cutoff valve;
• a liquid-side cutoff valve, where the gas-side cutoff valve and the liquid-side cutoff valve are disposed on opposite sides of a first portion of the refrigerant circuit;
• a sensor that detects refrigerant leakage from the first portion into a predetermined space;
• and
• a controller that sets a cutoff state in the gas-side cutoff valve and the liquid-side cutoff valve when the sensor detects the refrigerant leakage from the first portion into the predetermined space, wherein
• a cutoff leakage rate at the gas-side cutoff valve is a leakage rate of air when a temperature is 20° C. and a predetermined differential pressure of 1 MPa exists between an upstream side and a downstream side of the gas-side cutoff valve in the cutoff state,
• a cutoff leakage rate at the liquid-side cutoff valve is a leakage rate of air when the temperature is 20° C. and the predetermined differential pressure of 1 MPa exists between an upstream side and a downstream side of the liquid-side cutoff valve in the cutoff state, and
• the cutoff leakage rate at the gas-side cutoff valve is higher than the cutoff leakage rate at the liquid-side cutoff valve.