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Could my boiler really be cracked?

Hi Everyone,

I have a 13 year old Weil McLain 144K BTU gold oil boiler. About 3 months ago, we had our annual service, and the serviceman told us that when he opened the swing door to the combustion chamber, water started pouring out along with some reddish sludge which he identified as boiler sealant. When I went down to see it at his request, he told me that the water had stopped leaking and most likely the sealant had re-plugged everything up, He told us that the boiler was pretty much done and had to be replaced.

We moved into this house about 15 months ago, and for sure no one has added boiler sealant to our boiler since we've been here. That means that if it is indeed boiler sealant, it has been in the system for 15 month or very likely more. It's my understanding that boiler sealant is a temporary solution not intended to last more than a couple of months in the very best case. Could it actually be that it has been keeping the system up and running for 15+ months? We're well in to heating season this year (Boston) and I haven't noticed anything abnormal. Also, since moving in, I haven't added makeup water more than a little bit once or twice.

It seems pretty cut and dry that if water is leaking out, that the boiler needs replacement, but the fact that we haven't experienced any real water loss in 15 months leads me to believe that maybe nothing is wrong after all.

To all the pros out there - would it be possible for a cracked boiler to last so long with boiler sealant? If so, should I be replacing it at all or just waiting until some actual symptoms start showing up? Could the serviceman be mistaken? Is there another explanation for water leaking into the combustion chamber along with the red sludge?

Thanks in advance for any info,



  • Leaking boiler test

    To check for a leak, turn off the boiler, and when cool, over-fill to a point above the top. Let it sit for 8 hours or so, and check for signs of leakage in the combustion chamber.

    If there are no signs of drips, then drain down to the normal level, and use a clothes pin on the sight-glass rod to mark the level. Locate any valve supplying water to any auto filler on the boiler, and turn it off. Let the boiler run for 8 hours or so, watching for any sign of a lowering of the level.

    I don't think any boiler seal would hold up for more than a few weeks, but of course an auto-filler (a work of the devil!) can hide water loss.--NBC
  • icesailor
    icesailor Member Posts: 7,265
    edited December 2012
    Seeing Red:

    What did this red stuff look like? Was the whole bottom covered with water?

    With oil boilers that are warm start, and I consider steam boilers to be warm start because they don't have cold water being pumped through the boiler as it is starting up, there will be a red residue in the bottom of the chamber. That doesn't account for the water, but because Weil-McLain uses EPDM gaskets, one must be very careful using boiler seal in them. But if the boiler gets cooked, because the LWCO fails and doesn't shut it off, the gaskets are toast.

    There's a part missing here. Look inside the draft control. If the pipe is clean as a whistle, with no sign of anything in the sides of the pipe, you may have a leak or a really well running burner. Why did you call for service anyway?

    I'dd get a second opinion, maybe from someone here that works in your area. It's cheaper than a new boiler if you don't need one.

    Red like this.
  • JeremyN
    JeremyN Member Posts: 15
    Thanks for the replies

    NBC - I will try that test today and see what happens. The water level is a bit on the low side, so perhaps the leak only happens when it's filled up. How full is full though? To the top of the site glass or is there some other measure I should be using?

    Icesailor - When I was called down to see the boiler, everything had already been cleaned up. I didn't see any water but was told it was there. The red stuff is still all over my basement floor. He did his best to clean it up, but there are still streak marks everywhere. Last night I opened the chamber to take a look for myself, and I saw red, crusty stuff that had the texture of volcanic rock. Looking at your picture, it looks similar. I picked off a piece of it and it was crumbly. When I wiped it on the floor as a test it made similar streaks to the red stuff the guy claimed was boiler sealant. I can't be sure they're the same, but they at least look very similar. Would it be possible for an experienced boiler guy to mistake sealant for that normal crust stuff at the bottom of the combustion chamber?

    I just took a look inside the draft control and I'm seeing a brownish tinged surface (not rusty looking though) with patches of grey and white buildup in spots. Does that mean anything to you?

    Oh and we called for service just for an annual tune up. We hadn't noticed any problems.

    Thanks again to both of you.

  • icesailor
    icesailor Member Posts: 7,265
    Cracked up:

    Well, I'm not going to comment on whether it is leaking or not. Just experience and thoughts.

    I'm not an expert on steam by any stretch of the imagination. And the only ones I know to be really experts on steam I have found here.

    I would suggest that someone (a Wethead) who didn't have a lot of practical experience with steam boilers might not realize that a steam boiler is not a cold start boiler, even though it starts cold. Because it doesn't have a pump,as soon as the water in the boiler is over 140 degrees, the flue gasses will stop condensation. So, I would guess that said soot sucker boiler cleaner might have turned on the boiler to get it hot. He might have run it for 5 minutes or so and shut it off. If it was a nasty cold start water boiler, the crud is grey and black. Tons of it. But, your boiler will have the red stuff. If the boiler hadn't run long enough to get all the water vapors out of the crud in the chamber and out of the boiler sections, it might be wet. Once that stuff gets wet, it is not a pleasant job to suck the stuff out. Better cold. And if you spill it on the floor and get it wet, you need to call the Irish Cleaning Fairies to help clean it up. You need three buckets. One with water and TSP (Tri-Sodium Phosphate),one with clean water and the other with water that gets dirty after running the sponge through the mung. Any other way leaves red streaks on the floor. Or at least that has been my experience.

    What you describe in the exhaust is what I find in a well tuned and running Weil-McLain boiler.

    Crank up the thermostat and let 'er steam. If it goes up to pressure and shuts off, and you don't have a lake on the floor, I don't think that your boiler is leaking from what you describe. But that is MY opinion and mine only. Others here, far more experienced with steam may say likewise or otherwise.

    Good luck.
  • SWEI
    SWEI Member Posts: 7,356
    three buckets

  • icesailor
    icesailor Member Posts: 7,265
    Three Buckets:

    If you don't have the third bucket to get clean water on the sponge, you just drag the crud all over the floor.

    When I first started out in the trades during the Pleistocene Era, I worked for a mason. One of our offerings was to replace plaster/lathe ceilings. We would cover the floor and walls with poly, use cement blocks to raise the height for planks as staging, rip it down, replace it with Rock Lathe and then two coats of Structo-Lite and skim coat of hard finish lime plaster. Then, take everything down and clean up. The hardest thing to do was clean the lime if the floor. We used Vinegar in the clean bucket, wash the floor, rinse out in the first dirty bucket, then the next, then the clean. If the floor was getting white strikes, it was time to change some water. That was before the age of 5 gallon plastic pails.

    Soot from an old boiler being changed is an equal and is as difficult to clean up as the plaster.
  • Steamhead
    Steamhead Member Posts: 16,728
    edited December 2012
    I too, doubt that it's cracked

    but sometimes a leak won't show up as a lake on the floor.

    The proper procedure is as Nicholas said- with the boiler OFF and COLD, to fill it up past the top of the boiler into the steam takeoffs. If this does not make water leak into the firebox or onto the floor, the boiler is OK.

    Have a real Steam Pro do this, not the oil company.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • JeremyN
    JeremyN Member Posts: 15

    I'm in the process of running the test you guys described now.  I filled the water past the site glass and then let it run for a minute or so longer.  I'm not sure how to tell if it's up to the takeoffs.  Do I just feel the pipes to determine whether water has entered them?  I didn't want to overfill anything and screw something up. So I might be doing this test wrong, but so far, no leaks...

    Back when we were first told that the boiler was cracked, I set the wheels in motion for a gas conversion.  As of about a month ago, we now have a gas line coming up to our house which we paid the deposit for...

    I was all sold on the conversion, but with the boiler running so well for the past 3 months, and all the opinions here, I'm thinking that I jumped too quickly.  At the time I just didn't see how one could misdiagnose a leaking boiler.

    Upon thinking it over, it still probably makes sense to do the conversion considering the money we have tied up in the deposit (refundable with your first gas bill).  Massachusetts allows for a 7 year, interest free loan on heating equipment so long as it is greater than or equal to 82% efficiency for steam.  I figure that what we pay for gas along with the repayment of the loan will be about the same monthly bill as having oil.

    Oh well.  Lesson learned on my part.  I'm definitely interested in opinions one way or the other though, so if you think I'd be making a mistake with the conversion, please let me know.

    At this point I guess I could hijack my own thread and ask opinions on gas boilers for one pipe steam.  We had a number of estimates and everyone has pointed us to the Burnham P-IN5 which seems to be about the best going out there for gas.  Its also a size down from our existing boiler which is probably right given our EDR.  I've noticed that our system tends to run for about 45 minutes until shutting off on pressure (~2.1psi) and then cycles on for about 2-3 minutes and off for 1-2.  That seems really short.

    I've read a bit about the Burnham MegaSteam which is about 4% more efficient running on oil, but it seems like it's not approved for a gas burner yet.  Any idea on other, better options out there.? The P-IN5 is rated at 82.1% efficiency.

    Thanks guys,

  • BobC
    BobC Member Posts: 5,473
    couple of choices

    Find a steam pro and have him evaluate your boiler for using the Carlin Ezgas burner in place of the oil burner, when the boiler dies just move the burner to a new boiler.

    You can install a Smith G-8 steam boiler without a burner and have a factory approved EZgas mounted on it. It's a good combination.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • JeremyN
    JeremyN Member Posts: 15
    Smith/Carlin looks like an interesting choice!

    I did a little poking around here and I found an anecdotal efficiency number of 86.2% that certainly beats the 82.1% of the burnham. Is that typical? If so, why aren't these installed more often?

    Where can I find one of these in Eastern Mass? Everyone seems to be able to get WM or Burnham boilers, but I've never heard of anybody offering a Smith. I went to their website and then visited the suppliers page they recommended for my area. They didn't mention the G8 on that page though - just a few other models with more standard efficiency numbers.

    Also, I'm answering my own question from a few posts earlier about determining the water level in my overfilled system for testing. I went down stairs to check for leaks just now (still none) and realized that my 0-3 pressure gauge was registering .75 psi. Problem solved! 27 or so inches of water per psi so now I know. Looks like I have a bit more water to add.
  • Duff
    Duff Member Posts: 61
    raising the water level

    If you put a garden hose on the boiler drain and then loop the hose over your steam main when you add enough water to your system the water will start to come out of the hose. At this point your main is full and no water will get up to the first floor. Please make sure the boiler is cool and make sure the boiler drain is not clogged before you attach the hose.Good Luck