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Unable to drain water from steam boiler

JK_3 Member Posts: 240
there is also the possibility that there is no water in the boiler but just in th e sight glass. open the small drain on the lower sight glass valve an see if your mglass is clogged.

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  • Louis_4
    Louis_4 Member Posts: 4
    Unable to drain water from steam boiler

    I am a new home owner of a 1855 house in NJ. The last couple of winters I was able to drain the water from the steam heat boiler system, this year though no water comes out. The water level on the glass tube is 3/4 up. What could be preventing the boiler from draining out the old water?

  • Sounds like the drain is clogged

    To clear it we hook a washing machine hose between the clogged drain and a nearby heater and shoot full water pressure through the clog for a second or 2 .

    Gotta ask though , why are you draining water from the steam boiler ? Or do you mean you're draining water from the low water cutoff ?
  • Louis_4
    Louis_4 Member Posts: 4
    Clogged drain

    The previous owner had instructed me to flush the old water from the low water cut off at least once a month. I have not been able to do this anymore and I am becoming concerned.

    Thanks for your replies. I appreciate all the help and suggenstions from your forum.

  • Robert O'Connor_12
    Robert O'Connor_12 Member Posts: 728

    It is pretty important to have a fuctioning blow down valve working on that Low water cut off. I would get it fixed pronto! I would also add that in the Great State of New Jersey we currently use the 2006 International Mechanical Code, which located in section 1008.1 it says a full port valve shall be located in the lowest tapping. It then makes it quite easy to clean out when the main boiler drain clogs.

    Good Luck!

    Robert O'Connor/NJ
  • John_173
    John_173 Member Posts: 63
    blow down

    Louis -

    Just a homeowner here, but ....

    If this LWCO is a float type device - like the McDonnell-Miller 47-2 or 67 variants, you need to blow it down WEEKLY, I believe. Maybe more often under some circumstances. If you can't get a good flow of water from it and/or if (upon blowing it down) the burner doesn't shut down until the water level is restored, you need to get it fixed NOW.

    If you open the blow down valve & nothing happens, the float is mudded up. The LWCO has a finite life span & needs regular maintenance - more than simply blowing it down, but that is a place to start & within the responsiblity/ability of us lowly homeowners. (Actually, if you are reasonably adept, you might be able to do more.) My recollection is M&M says LWCO life span is something like 10 years.

    Don't neglect this, you can wreck your boiler.
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