[Rawknees'Turbo]

Do you have access to a nitrogen rig, even a small one?

When I did my install about 4 years ago, I used nitrogen to test for leaks in all my equipment fittings, adapters, and lineset hoses prior to doing any vacuuming of the copper lines and evaporator - I found at least three leaks at various fittings by putting a little nitrogen pressure in and using soapy water I applied with a small paint brush (had easy access to a nitrogen rig from the airport I work at).

If no nitrogen, you could test your equipment and fittings with air, however that will put air/humidity into the copper lines and evaporator, which is not ideal, but not a terribly big deal as you will pump them out later.

So in short, it is definitely worthwhile to test your equipment at this point.

You can test your gauge set with air, without having them hooked to the service ports, however that will not test the seal at the lowside line and the service port, of course (would need to plug the howside line end fitting, naturally).