Abstract: Refrigerant leakage in an air conditioner will affect its cooling capacity or even cause it to fail to cool. Therefore, air conditioners must undergo refrigeration system leak testing before leaving the factory. Some air conditioning manufacturers select refrigerant as a tracer gas, charging it into the indoor unit evaporator for system leak detection. In air conditioners, the refrigerant pressure at the indoor unit evaporator is higher than atmospheric pressure. During installation, the refrigerant (including tracer gas in the indoor unit) is released into the air. This results in issues such as cost waste and increased carbon emissions. A study on leak detection in the indoor unit system of air conditioning refrigeration equipment was conducted by referencing relevant sealing standards. Through theoretical calculations and experimental testing, the minimum charge level required for effective system leak detection was determined, thereby achieving cost reduction and carbon emission reduction.

Key words: Refrigerant leakage, Standing leak detection, Cost waste, Carbon emissions, Minimum charge amount