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Sight Glass / Water Level Question

1)I was messing with the site glass valves and not it is leaking  a little steam. Should the top and bottom valve both be all the way open (the ones directly above and below the sight glass)?

2)I went to flush the boiler with the lowest valve (with hose attached) and nothing came out. I was pretty surprised. Why didn't any water come out?


  • Charlie from wmass
    Charlie from wmass Member Posts: 4,314
    well good time of year to find issues

    #1 both valves full open hen a bit closed I usually go 1/8 turn. The stuffing box on the stem may need tightened.

    #2 sludge has it plugged. I use a heavy cable tie or a piece of copper wire and push it into the valve with it open and a bucket under the valve. Be prepared for that valve to not close all the way once you get it to flow. They make caps for hose threads make sure you have a washer for in the cap.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • sweetlou
    sweetlou Member Posts: 22
    Sludge Removal

    Thanks Charlie from WMAss. I am having difficulty getting anything in the pipe in order to drain the sludge.The pipe has a bend which makes it difficult to get anything in there to get the sludge moving. 
  • Jamie Hall
    Jamie Hall Member Posts: 22,877
    That's why

    you use a cable tie or a length of soft copper wire (try about 10 or 12 gauge solid)... they both should be flexible enough to get in there, unless the thing is not just plugged with sludge, but is caked on.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • sweetlou
    sweetlou Member Posts: 22
    Plumber visit today

    I had a plumber out today and he wouldn't even attempt to unclog it. He said he would have to take apart the boiler in order to drain it (at a cost of $450). He said the boiler should be drained weekly...in addition blowing out

    the low water cut off.

    Then he said I needed a new sight glass..there were small chips at the ends of the sight glass (cost $268).

    I was sort of shocked at the costs and told him I had to think about it. What do you think?
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    expensive repairs

    i suspect you have the wrong man for the job. the boiler should not be unnecessarily drained-only flushed!

    of course, when the sight-glass tube is cut, there are naturally a few dings, which are no problem. for myself doing the job, one hour is enough to take out the tube, scrub it with my mini bottle brush, and put it back on with new washers. during this time, as the boiler is off anyway, i can flush the boiler out through its drain, and then flush the returns, which may not be emptying all the water, but just enough to wash out the calcium.

    i prefer the arrangement with the steam pro to be charged on an hourly basis.

    there is no reason you could not learn easily to do these operations yourself!--nbc
  • Rod
    Rod Posts: 2,067

    Hi- I tend to agree with NBC about him being the wrong man for the job.  I normally drain my boiler twice a year, at the beginning of  the heating system and again  at the end of the heating season. The LWCO should  be done weekly or possibly more frequently if the boiler water is very dirty.

    Perhaps if you could post some pictures of the pipes going into the bottom of your boiler we might be able to make a better recommendation as to how you might unplug it.

    - Rod
  • sweetlou
    sweetlou Member Posts: 22

    Thanks for the feedback guys. I attached a couple of pictures. 
  • sweetlou
    sweetlou Member Posts: 22
    Boiler Drain

    I forgot to add that he said I would need a new boiler drain if he drained the boiler. The cost would be $232.
  • JStar
    JStar Member Posts: 2,752
    Get daring.

    Get a couple of buckets ready and spin out the whole boiler drain. The boiler should hold less than 10 gallons or so.
  • sweetlou
    sweetlou Member Posts: 22
    boiler drain

    I suggested the same thing JStar and he said it could really mess up things up inside. 
  • BobC
    BobC Member Posts: 5,470

    We don't usually discuss cost in this forum but to me, the costs this

    person is quoting indicates he really doesn't want the job. If he does

    get the job, he padded enough into it to ensure he has covered all the


    I suggest you get a qualified steam guy in to look at things and ask him if you can observe so you can learn what to do for normal maintenance.

    I had to replace my sight glass and gaskets last year and cost me about the cost of a 12 pack of Sierra Nevada's Pale Ale for the parts; I installed the parts myself in about 10 minutes and most of that was spent scraping what was left of the old gasket out of the bonnet nuts. Many years ago the tech replaced the glass and gaskets as part of the annual cleanout and the additional cost was pretty small. I usually tell the guy doing the annual cleanout to let me know if anything additional has to be done because he's already there and it saves the cost of another service call.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • Brian_74
    Brian_74 Member Posts: 237
    how it might mess things up

    If I had to take a guess, I would say that the plumber is worried about the nipple between the elbow and the boiler. If the boiler end is rusted in and the elbow end breaks, I imagine (I'm not a plumber) that would be a mess to try to fix.

    If you're going to remove the spicket (it's not the right kind for this job anyway), you might want to let some penetrating oil work its magic over night.
    1929 Ideal Heating vapor system.
This discussion has been closed.