Abstract: As the "double carbon" target is getting higher and closer, as a major energy consumer, the energy-saving requirements of household air conditioners are also constantly improving, and energy-efficient household air conditioners have been increasingly required to be widely used. At present, the main energy-efficient air conditioners in the domestic market are frequency conversion products, and the energy-efficient goal is relatively easy to achieve, but there is still a large demand for fixed frequency air conditioners in the overseas market in the short term, especially in the Middle East, Thailand and Israel. Mainly analyzes the influence of the key indexes of the air conditioner, such as the refrigerant charge, the design of the two air conditioners, the fan motor speed, the compressor displacement, on the air conditioning refrigeration system in this kind of energy-efficient air conditioner system. The influence of more or less refrigerant charge on the compressor and refrigeration system is analyzed, and the judgment method of whether the refrigerant charge is appropriate is put forward. The corresponding relationship between the displacement of compressor and the volume ratio of indoor and outdoor heat exchanger is analyzed, and the matters needing attention in the selection of high energy efficiency air conditioning system are summarized.

Key words: Energy efficient air conditioner, Refrigerant charge volume, Heat exchanger design, Motor speed, Compressor displacement