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Weil Mclain Boiler Rust - ticking time bomb?

ALIGA Member Posts: 194
Weil Mclain EG 250k BTU boiler, 23 year old boiler in newly purchased home.

Had the chance to take the top cover off, and found rust on the top, and am assuming in front of the jacket as well. I was fearful of removing the front cover, as I did not want to disturb the rust from falling off causing a leak.

Do you think I will be able to get by this season?

Any ideas why both tappings for the header piping would not be used?


  • Dave in QCA
    Dave in QCA Member Posts: 1,777
    Remove one more cover

    Aliga, it does not look good, but where you really want to look is under the next cover, the silver colored one.  Make sure the power to the boiler is off!

    Take of the next cover and you will be looking directly at the top of the cast iron sections, and down through the flue passages between them.  I keep my fingers crossed that you will not find anything worse that what we see in these photos.
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
  • Ban
    Ban Member Posts: 79

    Looks pretty normal for a 23 year old. You need to remove the flue to get a better look inside. Is it leaking? Attached is an image of what mine that I took last night. I have a 22 year old EG-55 that has a couple of pins broken but no leaks.
    Richard Ban
    Detroit, Michigan (Dunham 2-pipe vacuum)
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,573
    edited January 2013
    Ol' Rusty

    This would be a good time to start measuring the EDR of all your radiators, and then to start looking at new boilers of the right size.

    Certainly, using both tappings would have been better, as would making the header larger instead of smaller than the riser.

    I think it will last at least as long as it takes you to narrow your choices of boiler and installer.

    You could try reducing the stress on the boiler by keeping the pressure as low as possible.--NBC
  • Ban
    Ban Member Posts: 79
    edited November 2012
    Please Delete

    Richard Ban
    Detroit, Michigan (Dunham 2-pipe vacuum)
    ALIGA Member Posts: 194
    the silver cover

    I am assuming it is easy to take off, it looks like has some sort of sealant between the cover and the block.

    i will tackle that shortly.
    ALIGA Member Posts: 194
    EDR calcs

    I hope I calculated the EDRs correctly. 2800 square foot home.

    1st floor: 4 rads

    2nd floor: 6 rads

    Attic: 2 rads

    I have totaled all the rads to 335.7

    Since the mains are not insulated(one of my tasks to perform), should I multiply with a pickup factor of 1.5, and then x240?

    Total is = 335.7 x 1.5 x 240 = 120K

    Current steam boiler is EG65 with 250K input, Output of 209K

    Is it safe to say if I wanted to stick with a Weil Mclain, I can go with an EG-45?

    I am shocked the prior homeowner went from a 150k input to 250k input.

    Screen cap of weil mclain specs
  • Rod
    Rod Posts: 2,067
    Matching the Boiler to the EDR

    Hi- At a quick glance matching the EDR to the IBR ratings it would look like you could get away with a EG-40 as at 325 Sq.ft. of steam as it is very close to 335.7  Keep in mind that the net IBR ratings already have already included the "pickup factor".

    - Rod
    ALIGA Member Posts: 194
    edited January 2013
    Finally cracked

    took it down, cleaned up, next challenge getting new boiler up two sets of stairs and then down to basement, and finally got a 200k btu replacement(50k btu smaller than original weil mclain)
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,573
    edited January 2013
    Nice job

    Hope you were not too cold while the replacement took place!

    Don't don't don't forget the pipe insulation!!!!

    In the summer, you may need to enlarge, and raise up the header, if you have any wet steam this winter.--NBC
This discussion has been closed.