HPEC evaporative cooling unit with refrigerant pump is an integrated equipment that makes full use of natural cold source and low-power refrigerant pump to achieve the cooling of data room. The unit can automatically switch between compressor refrigeration, mixed refrigeration and refrigerant pump refrigeration. The unit can provide long-term, stable and efficient cooling, and is usually deployed on the roof or one side of the data center. Application scenarioses: large and medium-sized data centers, modular data centers, high heat density telecom equipment, computer rooms, etc