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Bcheap Member Posts: 1

We are working on a building in oakland that seems to have a clog in the condensate return line in a line of radiators. ie 121, 221, 321 and 421. We have tried to clear the line at the top floor using nitrogen and got water back in our face with only minimal water flow down to other floors(eventually) The first floor doesnt drain either, so it would be logical to think that at least one clog is between the first floor and the basement. Our only solution was to close all valve on that loop and try nitrogen again, and of course the pipe is too small to snake...any other suggestions?

Thanks in advance!


  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    Clearing return line

    Try using water, using an adapter on some kitchen sink faucet for a hose, and then adapters for the return piping. Water will work better than compressed gas, because of its mass, and not much pressure is needed.

    Is this 1-pipe or 2-pipe?--NBC