Pulling a good vacuum before charging a new system with refrigerant or after a repair is essential for the proper operation of an air conditioning system. Proper operation, system longevity, and the time you spend at the jobsite all relate to dollars in your pocket. In addition to the vacuum pump, a micron gauge is an essential tool. Below is a description of how the gauge works and why it is used in the HVAC industry.
The first is purging the system one to three times with nitrogen before the pump-down. The nitrogen absorbs moisture and can be released into the atmosphere without any harm. This reduces the start-up time even more.