high and low side on Guages

2003 HONDA CRV
188,800 MILES • 4 CYL • 4WD • AUTOMATIC
Avatar
JENKBYMOM
  • MEMBER
  • 1 POST
no issue just like to know why never open the red high side on gauges all other you tube video show to use both high and low side , thank you jax fl
Mar 29, 2026 at 10:13 AM
Advertisement
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
You can open the high side valve when vacuuming down the system only! Never open the red side when charging or the system is on, this can pump high pressure into the charge can/jug and make it explode. This is why we don't open the red valve. I never do, I just let is vacuum down through the low side. FYI.
Mar 30, 2026 at 7:54 AM