Food industry is a major industrial sector in Thailand, and Better Foods plants to install a refrigeration system with natural refrigerants (NH3/CO2) in their new cold distribution center. This refrigeration system employs an “indirect cooling method,” which uses ammonia to cool CO2 and then CO2 is transported to a cooler in a cold storage. By this method, ammonia is contained in the machine room alone and only CO2 is circulated in the cooler, ensuring the occupational safety. Also, the system uses approximately 20% less energy in comparison to conventional HFC refrigerators.