Which air conditioning system components must be approved or certified for use in an HFO-1234yf system?

In an HFO-1234yf air conditioning system, components such as compressors, heat exchangers, expansion devices, and hoses must be specifically approved or certified for use with this refrigerant. These components need to be compatible with HFO-1234yf's unique properties, including its flammability and pressure characteristics. Additionally, lubricants used in the system must also be compatible with HFO-1234yf to ensure optimal performance and prevent chemical reactions. It's crucial to adhere to manufacturers' guidelines and industry standards for safety and efficiency.