A temperature control method is performed by a temperature control apparatus including a heat exchanger configured to exchange heat using a phase change of a refrigerant, a rotary pump configured to receive the refrigerant from the heat exchanger and fuse the refrigerant with oil contained inside the rotary pump, and an oil refrigerant separator configured to receive the refrigerant fused with the oil from the rotary pump and separate the refrigerant from the oil. The temperature control method includes the steps of: circulating the refrigerant separated from the oil back to the heat exchanger; and adjusting at least one of a rotation speed of a rotor of the rotary pump, a position of a valve arranged at a connecting portion of the rotary pump and the heat exchanger, and a position of an airflow adjustment valve arranged at a connecting portion of the oil refrigerant separator and the heat exchanger.