Now I see why it was all night to pull this system down.
The pump was on the low side only when it should have been on both at
same time.
Been done in 1 hour. No More.
With this type of pump.
Now, since you pull this down only on one side the low, and let it go
all night long, how long did it hold the vacume?
The idea is to pull down system on both side, shut off both valve at
gauge and wait.
Wait for half hour to see if losing vacume down at all.
If this was not done big loss of time.
You could have leak still.
Now this purging I don't know why.
The lines are sucked down also at same time as system and have seals on
them.
The small amount of air is small at the fitting it is not important.
If profession gauges are used no problems to suck down or put in freon.
The most important is to wait after sucking down system to check for
leaks so all is good.
The time pulling down is not as important as this if you have a good
pump.

Good Evening.

Fred