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Uneven distribution of heat

millispillis Member Posts: 11

I live in an old apartment building roughly 110 years old. It has four unit lines, apartments A, B, C & D. We get our heat from an oil burner and most apartment have risers and old style cast iron radiators, all with air vents on them. Our boiler is quite new, purchased 2007 but we have severe problems with heat distribution. The apartments/units in the B line gets about 10-15 degrees LESS than all other units. Please note, we are the line the furthest away from the boiler. In order for us to get the bare minimum of heat (68 degrees) the other units get heated up to about 85 degrees. What can cause this? I am far from an expert in this area, really, I am just a tenant who observes what is going on. Could their be some sort of blockage in our pipes/riser? Do we need to ensure that all units have the correct size air vent on their risers/radiators? Should all tenants keep their valves open at all time? If I ever close my valve my radiator quickly fills with water and starts leaking. The building has 6 floors and 6 units in each line, 4 units on each floor. I am on the top floor of the line who gets very little heat. We have spent lot of time and money trying to figure out what the problem is, a plumber told me to get bigger radiators, I do not want to get bigger radiators because when we are above 30 degrees ALL apartments over heat and my bedroom becomes 88 degrees warm, with a bigger radiator I might reach close to 90. At the same time I am unable to shut my radiator off since it immediately starts collecting water and leaks. The conditions are almost unlivable and I am desperately looking for guidance and advice. Any help would be truly appreciated and I would not be able to thank you enough.


  • Eastman
    Eastman Member Posts: 927
    is this steam

    you might want to post in the steam section and add some photos so people can determine what type of system it is.
  • Jamie Hall
    Jamie Hall Member Posts: 23,272
    As Eastman said...

    you might do better in terms of replies on the "strictly steam" thread.

    However, that said...

    Since you mention air vents, I am going to assume for the moment that this is steam, and one pipe steam at that.

    In order for one pipe steam to work properly and evenly, it is essential that two major things happen (there are a bunch of others as well, but for the moment bear with me): you need to get steam throughout all the mains at about the same time, as fast as possible.  And, when you are dealing with a multi-story building, the risers need to get filled with steam in the same way.  This is done with main venting.  Therefore, if there are not main vents on the steam mains and -- since this is multi-story, at the tops of the risers, you need to have them installed.  What this will accomplish is to get the steam evenly distributed to the radiators.

    Then the amount of heat given off by the radiator is determined by the radiator venting.  If you want less heat, use a slower vent.  More heat, faster vent.  You cannot control one pipe steam with the valve at the inlet -- as you have found, unfortunate things happen when you try.

    That's sort of a basic starting point...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • millispillis
    millispillis Member Posts: 11

    Dear Mr. Eastman and Mr. Hall,

    Many thanks for your responses and as per your suggestion I have posted the listing in the steam forum together with pictures. Mr. Hall. I apologize for my limited knowledge but what does "main venting" mean?