Yes, as
@evilunclegrimace noted.
I’ll add that I like to leave the system sit overnight to see if it will hold vacuum at 30” (or less if you’re above sea level… 24” in Denver for example).
If it doesn’t hold vacuum you need to find out why.
You might benefit by studying a few threads before you continue.
Here is a long thread from earlier in the year; there are a lot of nuggets within regarding many facets of the process (charging with liquid, lubricating O-rings and fittings, evac / vacuum procedures, vacuum pump oil, gauge set "checks" to do prior to evac / charging, replacing the service valves, PAG oil distribution prior to 1st startup, etc.).
Hi, I have a 1996 C1500 4.3 reg cab 8ft bed and the A/C is not working, just blows ambient air. Is there anything simple I might be able to check to see if the system is salvagable? I was thinking if the system is bad, to maybe buy a kit or the individual parts needed to replace and flush...
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