Every YELLOW JACKET pump features an exclusive built-in indicator gauge to monitor the evacuation progress down to the green (29"-30") range. If the reading stays in the mid range, there is either high contamination or a large leak in the system.

If you think there is excessive moisture, blow out the AC&R system with dry nitrogen before connecting the vacuum pump to the system wherever possible. This reduces the amount of contaminants that must be "pulled" into the pump and increases evacuation speed.

Use a nitrogen regulator valve with pressure limited to 150 psi, and a frangible disc device set at 175 psig. When the indicator reaches the green (29"-30") range, the electronic micron gauge must be used for more precise readings.