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sight glass/ heat issues

My tenants say they keep having to manually fill sight glass to have heat work in the home. What is easiest and cheapest fix? thanks


  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    Fix the leak in the system, or replace the boiler.
    No Chemicals will do the trick, unfortunately.—NBC
  • Big Ed_4
    Big Ed_4 Member Posts: 2,782
    Fix the leaks , it could be the return pipe.(condensation leaks ) If you do not see any , it could be under the floor . Steam leaks , normally leaky vents , radiator valve packings or loose unions ...
    I have enough experience to know , that I dont know it all
    JUGHNE Member Posts: 11,060
    How often does it need refilling?
    Hopefully the LWCO stops the burner when the water drops low enough.

    Look for steam coming out of the chimney... :'(

    Or with the boiler off and fairly cool, overfill the boiler to the header pipes, let sit for at least an hour and look for water on the floor. :'(:'(

    Do you have return pipes under the floor?