A/C charging mistake

[mayoclan]

I completely replaced the A/C system on my 2000 4Runner Limited; compressor, condenser, evaporator core, expansion valve, drier and pressure switch. I vacuumed the system (no leaks) and while filling the system with R134 using a gauge set, I not only had the low pressure side opened i accidentally had the high pressure side opened also. After noticing the can of R134 wasn't emptying I realize what I did and closed the high side down. Then I proceeded with fill the system per the specs. Yes I started the engine, turned on the A/C and fan at the appropriate time.
Question..... by having the high pressure side also open briefly during the gas charging, does that screw up everything.

 

[FrenchToasty]

Yes, no air is to be in the system, if you had one or both ports open to atmosphere after you pulled a vacuum, you def sucked air in along with moisture. Sucks but I would re do it

 

[mtbtim]

No, it doesn't screw anything up but you're lucky the can of refrigerant didn't explode on you. You ONLY fill on the high side when the AC is OFF. Filling on the high side while the AC is running is dangerous because the pressure from the high side can travel up through the manifold gauge set, down the yellow service line and into the refrigerant can. It's perfectly fine to fill on high side when the AC is off. Many times AC techs will fill on the high side in a liquid state (can or cylinder turned upside down) because it's quicker and then they top off the system via the low side in the gas state while the AC is running.

Check out this video [MENTION=102606]infamousRNR[/MENTION] and I made servicing the AC system on [MENTION=142071]sunsetrunner[/MENTION] rig. It's a long video but we cover how to properly top off an AC system and also discuss how one would vacuum down and completely recharge their AC system.

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