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.

Air bubbles in my forced hot water baseboard heating

I have a two zone forced hot water baseboard heating system. I hear what sounds like air bubbles, or sane, running through zone 1, first floor, of my heating system. How do I purge the air our. There is a spigot below the valve, or one for each zone above the valve. Where should I connect the hose to drain the system? Or should I do something else?


  • tom_49
    tom_49 Member Posts: 269

    Shut off the power to the boiler, that way the valve will be closed. then attach the hose to the spigot above valve. open the valve slowly. you should hear water filling the boiler and should see air spitting out the hose.
  • Paul Pollets
    Paul Pollets Member Posts: 3,656
    Pumping Away...

    If the circulator pump is installed correctly...pumping away from the expansion tank and CW feed, there will never be air in the system after the first purge. If you're pumping towards the expansion tank and CW feed, you'll always have air, even after purging.

    See Dan's book "Pumping Away" available in the Online Store.

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • steve_29
    steve_29 Member Posts: 185

    You first need to understand why you have air in the system.

    If your air elimination devices are no longer working adding fresh water will only result in the same problem.

    Make sure your air elimination devices aren't corroded or disabled.
This discussion has been closed.