Refrigeration apparatus with shutoff valve

A refrigeration apparatus comprising:

• a heat source unit that includes a compressor and a heat-source heat exchanger, the heat source unit configured to function as a cold source or a hot source;
• a utilization unit that includes:
• a heat exchanger, and
• a first refrigerant pipe and a second refrigerant pipe connected to the heat exchanger;
• a first shutoff valve and a second shutoff valve whose opening degrees are adjustable, the first shutoff valve and the second shutoff valve being respectively provided at the first refrigerant pipe and the second refrigerant pipe;
• a refrigerant circuit including the heat source unit, the utilization unit, and a connection pipe;
• a refrigerant leakage detector configured to detect a leakage of the refrigerant from the refrigerant circuit;
• and
• a controller configured to
• close, upon detection of a refrigerant leakage, the first shutoff valve and the second shutoff valve;
• determine if a pressure error exists by comparing an acquired pressure against a predetermined threshold pressure value;
• adjust, upon determination of a pressure error, the opening degrees of the first shutoff valve and the second shutoff valve such that in an alert state, where the first shutoff valve and the second shutoff valve are both closed and a refrigerant leakage has been detected, the opening degree of at least one of the first shutoff valve and the second shutoff valve is increased, wherein
• the utilization unit further includes a casing housing the heat exchanger, and
• at least one of the first shutoff valve and the second shutoff valve is provided outside the casing.

A method of reducing a pressure of a refrigerant in a refrigerant circuit including a heat source unit, a utilization unit, and a connection pipe, the utilization unit including a heat exchanger;

• a first refrigerant pipe and a second refrigerant pipe connected to the heat exchanger;
• and a first shutoff valve and a second shutoff valve whose opening degrees are adjustable, the first shutoff valve and the second shutoff valve being respectively provided at the first refrigerant pipe and the second refrigerant pipe,
• the method comprising:
• detecting, by a refrigerant leakage detector, a leakage of the refrigerant;
• closing, by a controller, the first shutoff valve and the second shutoff valve in response to detection of the leakage;
• acquiring a pressure of the refrigerant;
• determining if a pressure error exists by comparing the acquired pressure against a predetermined threshold pressure value;
• and
• adjusting, upon determination of a pressure error, the opening degrees of the first shutoff valve and the second shutoff valve such that in an alerts state where the first shutoff valve and the second shutoff valve are both closed and a refrigerant leakage has been detected the opening degree of at least one of the first shutoff valve and the second shutoff valve is increased.