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low water level?

I just discovered that it is generally understood for the water level on Weil-McLain boilers to be at the halfway point in the gauge. On our 588 Series 1 it is quite a bit lower. Is this something to be concerned about?

Links to photos:

<a href="https://www.dropbox.com/s/g7595hv5457rw74/water%20level%20closeup.jpg">https://www.dropbox.com/s/g7595hv5457rw74/water%20level%20closeup.jpg</a>

<a href="https://www.dropbox.com/s/5rqn5ktzt6w0bdi/water%20level.jpg">https://www.dropbox.com/s/5rqn5ktzt6w0bdi/water%20level.jpg</a>

A photo from 2011 showing the water level as like now.

<a href="https://www.dropbox.com/s/fjy51coke8ro1jz/water%20level%20from%20base%20of%20boiler.jpg">https://www.dropbox.com/s/fjy51coke8ro1jz/water%20level%20from%20base%20of%20boiler.jpg</a>

The manual says it should be halfway (p. 21).

<a href="https://www.dropbox.com/s/zu4q3w6q14svpxv/WM88series1boilermanual.pdf">https://www.dropbox.com/s/zu4q3w6q14svpxv/WM88series1boilermanual.pdf</a>


  • Jamie Hall
    Jamie Hall Member Posts: 23,456
    Not really....

    So long as the low water cutoff isn't giving you fits.  Some boilers are set up to run higher (the one in the museum I care for runs about 3/4 of the way up the glass) and some are set up to run lower.  If you have an automatic water feeder, it will pretty well govern how low you can go.  If you are feeding manually, you can be as fussy as you like!  Only suggestion I'd have is if you are feeding manually, don't do it until the system has been off for a while -- 15 minutes at the very least -- to let all the return water that is going to return return.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Mike Kusiak_2
    Mike Kusiak_2 Member Posts: 604
    Water level

    According to the manual, the water line should be 49" from the floor. You might take a tape measure and confirm the sight glass water level agrees with this.
  • HoyteKing
    HoyteKing Member Posts: 85
    water line to header not 24"

    You are referring to figure 16 on page 13.

    From FLOOR to water line - 49"

    I do not know the standards on measuring the water line to the header, but am an English teacher, and taking the preposition "to" as written, would interpret the 24" to be to the BOTTOM of the header. I measured the header from top to bottom and came up with a width of 7" (please note that I do not know how to properly measure a pipe circumference).

    Water line to bottom of header - 16"

    Water line to mid-point of header - 19 1/2"

    Water line to top of header - 23"

    The Kenawee Smokeless Firebox No. 111 sits in a pit. The Weil-McLain does not. I think the installers could not get enough clearance to make the header higher without making an approximately 6" pit for the new boiler. I bet they realized it after getting the boiler in place, and said **** it.

    The header is large, but not high enough. Is this a problem?
  • Jamie Hall
    Jamie Hall Member Posts: 23,456
    The header

    is too low -- but this may not be a real problem (although it could have been solved).  There are two purposes to a header.  One is to take the steam from the boiler risers and  distribute it to the steam mains and, at the end, connect to the equalizer.  The other is to ensure that the steam going to the mains is "dry" -- that is to say, that it doesn't contain droplets of water.

    The droplets of water are there because they are carried up from the boiler through the risers.  If the risers are big enough and tall enough -- that's your 24 inches -- most of them, if not all of them will drop out of the steam rushing up the riser and just fall back into the boiler.  If the risers are too small or too short, they will be carried along to the header.  Now if the header is big enough, the steam will slow down inside it, and the water droplets will fall out, flow along the bottom of the header, and get back to the boiler through the equalizer.

    Yours may well be big enough to do that.

    How do you tell?  If you are getting "wet" steam -- with droplets of water -- you will also be very liable to getting water hammer in the mains, even if the pipes are all pitched properly.

    Would it be better if the riser were higher?  Probably.  Even better would have been to go up and over and down again with the risers, and using a drop header.

    Is it working for you?  If so, I'd leave it.

    There are a couple of other points here.  First, having your boiler water level lower, but still within the sight glass, helps a lot in mitigating the potential problem of the low header, since the dimension in question is from the water level in the boiler to the header.

    The second point was probably quite unintentional -- but fortunate.  Your old Kenawee sits in a pit, and may have had a slightly lower working water line than your new boiler.  Putting the new boiler in at a higher elevation pretty well guarantees that any wet returns in your system stayed wet.  A dismayingly common failing in new boiler installations is lowering the water line and letting what were wet returns become dry -- at which point all sorts of miscellaneous and puzzling problems occur.

    There is one other possible problem with the low header.  If the dry returns -- if you have any -- are also low, there is a chance that pressure in the boiler could hold up drainage from the dry returns enough to allow water to stand in them, rather than draining out as it should.  However, if you keep the pressure nice and low, this shouldn't be a problem.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • HoyteKing
    HoyteKing Member Posts: 85
    no header return, BUT no water hammer, BUT no balance in heat

    Thank you again for the advice.

    We have no water hammer. We were told by the local Chicagoland steam guru that the pipes are larger and so may compensate.

    The pressure was up to 2psi three years ago before I started actively intervening. Higher pressure was the idea to get heat into cold units. I had water spitting out of my bathroom radiator. Now it is at .5 psi.

    Since the farthest units are not getting heat, and we now have insulation, I was thinking we have wet steam. Of course, some insulation was removed by the man in charge of the boiler to "heat his basement and floor" because it was too cold. He had poor heat before that move, though.

    We have a dry return (I think) that is above the water line. There is piss poor main venting, though.


    There is no header return (see photos). I was told that this needs to be done by the local Chicagoland steam guru. The temperature differential is between 4.2 and over 7 degrees among the three runs. My unit is smack in the middle and the only one with perfect heat.

    We also have one teeny tiny Gorton attached directly in the line for main venting (see photo). Three other main vents were improperly placed by a contractor who knows air conditioning (a decision making issue).

    So, my main push is to get "additional" main venting and a header return done. I have been asking about other things here such as: water level, bullheaded tees, F and T traps, and insulation to get other questions out of the way. I am expected to have answers, but at the same time can be ignored as "we are not experts."

    The pipes have been hissy lately. This may be because the neighbor in charge of the boiler is messing with the cycle. The cabal advocates balancing the system using the control and 7 temperature gauges. They may rethink that as I asked them if they liked it that way 4 years ago (spoiler - wow, was it hot!).

    As I wrote on another thread, we are looking for a contractor who knows steam in the Chicagoland area. The local steam guru is backed up for 4 months due to his extreme level of competency. He would come out then, despite my neighbors, as I make an effort to genuflect and beg, but is not enthusiastic. I sympathize.

    Dropbox links (having trouble uploading photos):

    return into boiler -


    where the header return is supposed to go -


    main venting (shot shows a bullheaded tee I think; where insulation removed; main vent) -


    improperly placed main line vents (notice they are flush with a heating duct) -


    the header coming out of the boiler (good welding job) -


    return lines and condensation tank (2011 before insulation put on) -