Purging the ac gauge manifold

[atlsud]

What are the steps to purging the manifold of air when the system is empty?

The videos I've seen use the pressure in the system to purge the low and high side tubes and purge the yellow tube from the new refrigerant can. How do you purge the low and high side tubes when the system is under vacuum?

Thanks in advance!

 

[55trucker]

Hi there:

if the system is presently under a possible vacuum a set of manifold gauges & a pump must have been used to do so, I'm assuming that they were disconnected from the system before a charge was applied?

If that's the case you should do the vacuum process again to ensure that a proper vacuum is still there in all the lines before applying the charge. Take nothing for granted.