The TE-VG1 is built with an advanced solid-state vacuum sensor that can precisely measure the vacuum level. The vacuum gauge is used for monitoring vacuum level progress when servicing HVAC&R equipment. From the measurements you can gather information about the evacuation and dehydration progress. Once vacuum requirements are met, the system can be charged with refrigerant. In addition to verifying a proper vacuum, the digital vacuum gauge can perform a timed vacuum decay leak test. The vacuum gauge has a battery life of 100 hours.