A/C
Senior Member
True Car Nut
Joined: Oct 2002
Posts: 2,703
Likes: 0
From: Groton, CT _NEBF 05, 06, 07_

A reputable A/C service mechanic will first check the R134a state of charge. They usually connect a roughing pump to the A/C system to pump it down to hard vacum, then do a drop test under vacum. This also removes any non-condensable gases from the system. Once strenght & tightness (air tight integrity) of the system is established, they should re-fill with a specified amount of compressor oil & refrigerant R134a.
Originally Posted by markwb
A reputable A/C service mechanic will first check the R134a state of charge. They usually connect a roughing pump to the A/C system to pump it down to hard vacum, then do a drop test under vacum. This also removes any non-condensable gases from the system. Once strenght & tightness (air tight integrity) of the system is established, they should re-fill with a specified amount of compressor oil & refrigerant R134a.


