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I keep having to refill my steam boiler very often when it's very cold outside?

lobsterbiscuit Member Posts: 1
Hi there,
I have a steam boiler with the vertical glass tube-guage of water, and a lever you use to top off the water in the tube whenever the heat stops working.

My local maintenance guy said that you usually need to re-top it off every 3-4 days, but as the weather has been getting colder, I've noticed having to do it every 2 days or so. Maintenance guy is out sick right now, so just wanted to see what y'all thought - is it normal for one to need to re-top more often when very cold outside? For reference, in the past it was around 20some Fahrenheit, and today it dropped to 10 degrees Fahrenheit, and I needed to refill it again within 5 hours.

I don't have a chimney, and there aren't any leaks in the apartment or anything else strange.



  • Jamie Hall
    Jamie Hall Member Posts: 23,441
    No, it is not normal. You may not see any overt leaks -- but that water is going somewhere, and that means a leak.

    Further, that it is needing more water when it is working harder means that the problem is a steam leak.

    There are many minor possibilities: check all the radiator valves; you may hear them hissing when the boiler is running. If this is one pipe steam, check all the vents on the radiators. They may not be closing properly -- it is two pipe, check the main vents, as they may be leaking (they might with one pipe too!).

    If it is truly two pipe, with dry returns, check them for drips, particularly at any pipe fittings. Even a small drip which you may not otherwise notice can add up pretty fast.

    Then, of course, there is the boiler itself. The boiler exhaust has to go somewhere, chimney or no chimney, so take a look there when the boiler is running. There may be a thin cloud, but billowing clouds are a real problem.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • KC_Jones
    KC_Jones Member Posts: 5,742
    First what the maintenance person told you is definitely wrong. You shouldn't need to add water in any temperature more than about once per month.

    If you are adding water every 2 days due to it being off on low water, you have some kind of leak and it needs to be found, excess make up water is one thing that will shorten the life of the boiler.

    Do you have any underground return pipes?

    Steam leaks are challenging because steam is invisible. Need a mirror and go around to vents, valves, basically any place a leak may occur and see if you get water on the mirror. Any water indicates a leak and needs to be addressed.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
    JUGHNE Member Posts: 11,076
    If the system lost enough water for a refill in 5 hours you should see a definite water leak... if within the building.

    If you don't notice a massive leak inside then it is either out the chimney or under the floor.

    Are you a tenant or the owner of the building?

    Can you post pictures of the boiler from floor to ceiling from all possible angle/sides?