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.

Expansion tanks, trapped air

Options
CBRob
CBRob Member Posts: 273
I think all of these tanks are allowed to be installed vertical. How would the trapped air ever get out?

Comments

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,631
    Options
    With a bladder tank there is always air on one side of the bladder and boiler water on the other side. The expansion tank acts as an air cushion to keep the correct pressure in the system.

    Wit a bladder tan you need automatic air vents or manual air vents or a air scoop or microbubble eliminator to remove the air from the system.
  • CBRob
    CBRob Member Posts: 273
    Options
    Wouldn't air be trapped under the bladder when the threaded end is down?
    I've always installed them threads up.
  • Intplm.
    Intplm. Member Posts: 2,009
    Options
    CBRob said:

    Wouldn't air be trapped under the bladder when the threaded end is down?
    I've always installed them threads up.

    Nah. After some time the water will absorb the air if any is there at all.
    CBRob
  • hot_rod
    hot_rod Member Posts: 22,263
    Options
    thread up is preferred, thread down or horizontal are acceptable, according to Zilmet instructions.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream