CMF room-based inverter CRAC (refrigerant pump) can use atmospheric natural cold source for cooling computer room. The natural cooling efficiency of CRAC with refrigerant pump is 10 times that of compressor refrigeration mode at low ambient, which can effectively reduce the PUE value of the room. Application scenarioses: data center, telecom equipment and computer room, electronic instrument workshop, museum, archives, high-grade wine cellar, medical equipment room, constant temperature and humidity laboratory, etc.