Abstract: The technique of helium n1ass spectrometer leak detection has been used in air conditioner production,Which brings benefits obviously. The pressurezing sniffer counterflow tecLnique was designed in the air conditioner leak detection, it can be divided three systems:pressure helium systein,heliummass spectrometer leak detection system and retrieve helium system. All they operate automaticaly.The efficiepJcy of retrived helium is higher than 90%. Another equipment is developed for air conditoner refrigerator and evaporator leak detection. Its can detect refrigerator or evaporator with the speed of 50s for every refrigerator or evaporator and thc sel1sitiyity 10^-9 Pa·-m³/s.