Can you seal an ac unit from air with a Vaccum Pump?

I am looking for knowledge not for someone to tell me to take it to a mechanic. The issue I am running into is the vaccum pump I bought only blows air out, no since the theory is to seal air out, do I need to buy a vaccum pump the blows air into the system or out of the system?

8 Answers

  • 4 weeks ago

    A vacuum pump always sucks the air out of the AC lines .Usually a inert gas is blown thru the lines to clear out any crap .But the name says it all it vacuums the air out of the lines before refrigerant is introduced the system  A blower blows ,and a  vaccum sucks ..Not doing this step correctly can cause serious issues later if all the air is not removed ,and I mean ALL OF IT the refrigerant can be contaminated by moisture Moisture in the air that's trapped in in the lines still So the vacuum should be run with a gauge attached ,sometimes for a couple hours Depending on the vac pump you have .But DO NOT BLOW ANY AIR unless it's a inert gas .BUT NEVER AIR Good luck 

  • 1 month ago

    A vacuum pump sucks to create a vacuum in whatever it is connected to. Any air it vents is whatever it has sucked.  Do try to understand this.

  • M.
    Lv 7
    1 month ago

    I've answered several of your questions about this car and its air conditioning system. 

    A vacuum pump sucks air.  It sucks the air out of whatever you connect it to. 

    Vacuum is the opposite of pressure.  Or, vacuum is negative pressure. 

    You have some problem understanding some things.  You keep saying something about sealing an air conditioning unit.  I don't understand what you are thinking or why. 

    Can you show an internet site with your exact vacuum pump?  Or give the brand name and model number?  I would like to see it. 

    Do you have a dual gauge set? 

    Air conditioning repair is rather complicated.  Many things are involved.  Procedures must be done a certain way and in a certain order.  Everything must be extremely clean.  Cleaner than food!

    -General automotive mechanic since 1972

  • Snezzy
    Lv 7
    1 month ago

    How can I say this without sounding as if I am insulting your misunderstanding? You have already received at least one answer that was correct, but apparently you misunderstood it.

    Here are a couple of videos about automotive AC repair:

    Youtube thumbnail

    Youtube thumbnail

    The first one is "for beginners".

    Please try to gain an actual understanding of what is going on, rather than just guessing. Every person, every one of us, who naively decides to "fix" the AC by just adding more freon does it wrong. Sometimes we don't bother to follow the directions or don't have the right equipment. Occasionally we have mistaken beliefs that get in the way of our understanding. Almost none of us can spell "vacuum" without help from a spell-checker, a dictionary, or a spelling-Nazi like me.

    Now a word of encouragement... Many people have learned how to do AC repair correctly. You can, too, but sometimes genuine Trial And Error, augmented with "back to the books," is necessary. You're part way there but are still missing some important knowledge.

  • What do you think of the answers? You can sign in to give your opinion on the answer.
  • Anonymous
    1 month ago

    14 questions about that POS - you obviously can't fix it but get pissed when folks tell you to take it to a pro - so stop asking.


  • 1 month ago

    Vacuum pumps suck air out of a system. I'll be you are just as confused about "blow jobs"!

  • Bill
    Lv 6
    1 month ago

    You need one that sucks air out of the system. It isn’t a vacuum pump if it pumps air in. 

  • Anonymous
    1 month ago

    Please see a mechanic preferably one that specializes on your car's make.already.  You have been trying to fix your car's AC for a month.  You are either entirely clueless on how car AC systems work and how they are fixed or you are just trolling.

Still have questions? Get answers by asking now.