Heating and refrigerating circulator refers to a circulating device that provides heat and cold sources for reactors, tanks, etc., and is a laboratory instrument with dual functions of heating and cooling. Mainly used for supporting glass reactors, rotary evaporators, fermentation tanks, calorimeters in the chemical, pharmaceutical and biological fields; widely used in petroleum, metallurgy, medicine, biochemistry, physical properties, testing and chemical synthesis research departments, universities and colleges , factory laboratory and metrology quality inspection department.