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.

waterfall sound inside radiator.

meticulousmike Member Posts: 31
edited January 2016 in THE MAIN WALL
i think that this CI radiator is piped in wrong and when cold,purged until steady water stream and up to system pressure 12-15 psi it sounds like a waterfall when the pump is running..when it's heated of course the sound goes away almost entirely.i'm thinking that jacking up cold pressure to not overpressurize the system when fully hot and expanded might do the trick or be a waste of time because no matter what it's not plumbed in correctly.what are the wrong ways to plumb into a cast iron radiator? no, i didn't plumb this in.the owner had to re-plumb the whole building water and boiler systems after the copper was stolen so it looks like he just followed the same route as was previously done,if that was correct ... thanks for the help.

There was an error rendering this rich post.


  • Gordy
    Gordy Member Posts: 9,546
    Funny usually air noise gets worse when water is heated bringing air out of solution.

    Yes raising system psi can quite things down.

    I think the replumb may have made purging more difficult. And air is still in the system. How long are you purging, and is it high psi? Can you isolate the system from the boiler for power purging?
  • Eric_32
    Eric_32 Member Posts: 267
    If your using the coin vent on the radiator itself as the only means to purge air, the piping below the radiator should be pitched up to the radiator.

    If there are any dips in the piping air will be trapped and difficult to remove through that radiator vent. If that is the case, a purge station could be added on the piping below or possibly at the boiler to force bleed the air in the piping and then use the coin vent on the radiator to finish bleeding the air from the radiator.

  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
    I have seen these radiators piped both ways, and done right, can work fine. But in order for it to work correctly, the system circulator HAS to pump away from the expansion tank connection.

    Got boiler pictures? I'd guess that it is on the return pumping towards the expansion tank...

    Are the radiators piped in series as well? Common problem with untrained people working on these systems.

    Get pictures and get back to us.


    There was an error rendering this rich post.