Refrigerant circulation device

Abstract

A refrigerant circulation device includes a primary flow path, a secondary flow path, a valve, and a controller. The primary flow path allows circulation of a primary refrigerant. The secondary flow path allows circulation of a secondary refrigerant. The valve is provided in the primary flow path or the secondary flow path, and includes an opening degree that is adjustable. The controller is configured or programmed to control operation of the valve and cause the valve to perform a predetermined operation when a period during which the valve is not operated exceeds a threshold value.

What is claimed is: 
     
         1 . A refrigerant circulation device comprising:
 a primary flow path that allows circulation of a primary refrigerant;   a secondary flow path that allows circulation of a secondary refrigerant;   a valve that is provided in the primary flow path or the secondary flow path, and includes an opening degree that is adjustable; and   a controller configured or programmed to control operation of the valve and cause the valve to perform a predetermined operation when a period during which the valve is not operated exceeds a threshold value.   
     
     
         2 . The refrigerant circulation device according to  claim 1 , further comprising:
 a heat exchanger connected to the primary flow path and the secondary flow path;   the primary flow path including:
 a main flow path that connects an inflow port and an outflow port that are for the primary refrigerant via the heat exchanger; and 
 a bypass flow path that branches from the main flow path at a position upstream of the heat exchanger and merges with the main flow path at a position downstream of the heat exchanger; and 
   the valve including:
 a first valve connected to the main flow path at a position not only downstream of a branch position of the bypass flow path in the main flow path but also upstream of the heat exchanger; and 
 a second valve connected to the bypass flow path; wherein 
   while one of the first valve and the second valve performs the predetermined operation, the controller is configured or programmed to cause the other of the first valve or the second valve to open.   
     
     
         3 . The refrigerant circulation device according to  claim 1 , further comprising:
 a temperature sensor provided in the secondary flow path; wherein   the controller is configured or programmed to cause the valve to perform the predetermined operation when not only the period during which the valve is not operated exceeds the threshold value but also when a liquid temperature of the secondary refrigerant acquired from the temperature sensor is within a predetermined temperature range.   
     
     
         4 . The refrigerant circulation device according to  claim 1 , further comprising:
 a pressure sensor provided in the primary flow path; wherein   the controller is configured or programmed to determine whether to cause the predetermined operation to be performed in accordance with a measurement value of the pressure sensor and an opening degree of the valve.   
     
     
         5 . The refrigerant circulation device according to  claim 1 , further comprising:
 a sensor provided in the primary flow path or the secondary flow path; wherein   the controller is configured or programmed to check whether the sensor normally operates based on change in measurement values of the sensor during the predetermined operation.