Repairing leaks sometimes can be pretty easy. This customer called about his air conditioner not cooling. After a thorough search with an electronic leak detector, no leak could be identified. from the evaporator or condenser coils. This was puzzling since my gauges were saying the unit had very little pressure when I arrived. In order for me to check for leaks, I added about 2 ounces of refrigerant and then pressurized the system to 150 pounds pressure with Nitrogen. But even after the system was pressurized there was no evidence of a refrigerant leak.
Then I decided to remove my hoses to double check the service valves. Right as I was removing the liquid line hose, I discovered a significant leak from the service valve. Unfortunately, Goodman had decided to change the service valve design and the standard valve core removal tool would not work. Using some creativity, we found a service valve adapter from the parts supplier and mounted the adapter over the leaky service valve creating a new service valve without having to braze in a replacement valve.
The system was then pressurized with nitrogen to check for any additional leaks before the next step, vacuuming the system down to a total vacuum, or as close as you can get at 500 microns. This video is shown at the stage of where the system is in a state of vacuum but not yet at the point of 500 microns as required by the EPA. It also shows the adapter added to the liquid line service valve.