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Trying to Remove air in baseboard pipes

Sampson63 Member Posts: 3
My expansion tank had leaked for a day before it was found. Since then, I can hear the "rushing water" sound in the pipes. I want to bleed the air out of the system, but don't know where to start. It's a Hydronic system in a 1 floor ranch. I've opened up the small valve on top of the American Air Purger valve and got some hiss, then hot water. Done this several times, same result. Is there a faster way to do this?


  • BornForDying
    BornForDying Member Posts: 40
    If you take some pictures of the piping and valves near the boiler we can tell you exactly which valves to turn. It's a fairly simple process. There are many youtube videos on the subject if you are into that.
  • Sampson63
    Sampson63 Member Posts: 3
    JUGHNE Member Posts: 8,931
    Do your baseboards have air bleeders on one end under the end covers?
  • Zman
    Zman Member Posts: 6,973
    The air vent is supposed to be automatic. Hot water should not come out when you open it. It should let the air out, the then close on it's own. Operating it manually to remove the air will be a long process.

    Your system is piped with the main circulator pumping into rather than away from your expansion tank. This makes air elimination more difficult, but it usually comes out eventually as long as you maintain flow.

    Swap out the air vent and the problem should take care of it's self....
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • Sampson63
    Sampson63 Member Posts: 3
    Baseboards don't have bleeders under covers