Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

how does air get into ac system?

System pressure higher than atmosphere pressure how air get into ac system?

Comments

  • HVACNUT
    HVACNUT Member Posts: 4,623
    If your gauge manifold and hoses aren't primed and you add refrigerant, that will introduce air into the system. 
    If you're talking about a system that was never touched, then all of a sudden had air, then it either went into a vacuum, or it was there from the beginning. 
    STEVEusaPA
  • ChrisJ
    ChrisJ Member Posts: 13,071
    Like @HVACNUT said, guys not purging their hoses / manifold before connecting, or improper dehydrating during installation. Those are probably by far the most common reasons.

    There's also systems out there that go below atmosphere on the low side during operation, they can suck air in during operation if there's a leak.

    Some refrigerants and oils may break down and produce non-condensables for various reasons as well.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • pecmsg
    pecmsg Member Posts: 2,954
    edited June 10

    System pressure higher than atmosphere pressure how air get into ac system?

    Improper evacuation procedures.

    The refrigerant will always be at a higher pressure then Zero at above 0°F temperatures with a few exceptions! R-11 being one of them. O PSIG @ 75°F
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 3,334
    edited June 10
    I remember hearing about a plumber that would pressure test his linesets before putting refrigerant in the system. And what is every plumbers best friend when pressure testing pipes? Water. It will let you know where the leaks are better than any air or gas pressure test! Y'all can see the water right away.

    He had a lot of failed compressors the first few years he started doing air conditioning work. But could not figure out why?!?
    Edward Young
    Retired HVAC Contractor from So. Jersey.
    Services first oil burner at age 16
    P/T trainer for EH-CC.org
    pecmsg
  • johnjohn89
    johnjohn89 Member Posts: 65
    HVACNUT said:
    If your gauge manifold and hoses aren't primed and you add refrigerant, that will introduce air into the system. 
    If you're talking about a system that was never touched, then all of a sudden had air, then it either went into a vacuum, or it was there from the beginning. 
    Great answer! Thank u
  • johnjohn89
    johnjohn89 Member Posts: 65
    pecmsg said:
    System pressure higher than atmosphere pressure how air get into ac system?
    Improper evacuation procedures. The refrigerant will always be at a higher pressure then Zero at above 0°F temperatures with a few exceptions! R-11 being one of them. O PSIG @ 75°F
    Thank u 🙏!
  • johnjohn89
    johnjohn89 Member Posts: 65
    ChrisJ said:
    Like @HVACNUT said, guys not purging their hoses / manifold before connecting, or improper dehydrating during installation. Those are probably by far the most common reasons. There's also systems out there that go below atmosphere on the low side during operation, they can suck air in during operation if there's a leak. Some refrigerants and oils may break down and produce non-condensables for various reasons as well.
    👍 
  • johnjohn89
    johnjohn89 Member Posts: 65
    @all thank u so much