Weil McClain LGB-9

ChrisL

I've got an LGB-9 installed in one of my apartment buildings that was installed in 1998. The past two seasons, there is a small weeping leak from the two end sections on the bottom where they meet together. This weeps over the Summer, and then once the heating season starts, it goes away in a few days. Has me a little concerned, and am wondering if I should look at replacing it, taking apart the two end sections and re-sealing, or leaving it alone. Any comments?

Thanks,

ChrisL

Fred

I assume this is a steam installation? It's probably giving you notice thatit's going to give you a real problem one of these days. It probably doesn't stop weeping during the heating season. The boiler block is just hot enough that it evaporates. Leaking on the end sections is often due to stress from expansion and contraction when the risers out of it to the Header doesn't have the appropriate swing joints. Are there two risers out of that boiler? Were they installed properly? It may be too late to do much about it on this boiler since it is 17 years old but you'll want to make sure the replacement is done properly.

Abracadabra

pics of the boiler?

ChrisL

Here are some pics. Upon closer inspection, I am thinking the small leak is still ongoing, as the corrosion seems to have grown in the past few months.

ChrisL

Fred

Yep, That's an on-going leak. Keep a close eye on those burner tubes to make sure they don't get cloged with rust and debris. I don't know if you can limp along until warm weather but it should be replaced before next season for sure.

ChrisL

Yes, I replaced a couple burner tubes earlier this season. What I need to figure out is if I should have the section taken apart and re-sealed, or is it time for a new boiler.

BobC

The boiler is 17 years old and has been leaking a couple of years that you know of. The question is exactly what is leaking and how much of the rest is ready to let go. Fresh water is a good way to kill any steam boiler because fresh water brings in oxygen and oxygen causes corrosion. Leaks have to be found quickly and fixed for good boiler longevity.

Do you have any idea how much water was being added per day, per week, or per month?

Somebody has to closely examine that boiler to see if its corrosion is localized or widespread.

Bob

Fred

ChrisL said:

Yes, I replaced a couple burner tubes earlier this season. What I need to figure out is if I should have the section taken apart and re-sealed, or is it time for a new boiler.

That's a tough call. Being 17 years old, I'd be afraid that once someone gets in there, they are going to find other rot issues and you end up having to put a new boiler in anyway. Even taking that one apart and trying to put new gaskets or push nipples (I think Weil Mclain uses a rubber or composite material between the sections) might cause other sections to leak and the cost of doing that work may well be close to the labor associated with installing a new boiler. Weigh your options carefully.

nicholas bonham-carter

If you want to repair, then I would suggest all sections be replaced at the same time.
Compare that cost of repair to the cost of a couple of smaller boilers sized precisely to the EDR of your radiation, (may be smaller than your present boiler). The new pair could be stage fired for economy. Smaller boilers could be easier to move down the stairs as well.--NBC

KC_Jones

In addition doing a full EDR calculation on the building might show you are oversized already with what you have. This is pretty common again replacement with a possibly smaller or as NBC said 2 smaller boilers would add economy. I have a feeling that leak is worse than you think. Have you observed the chimney from the outside to see how much steam is coming out? Also if it is "just a gasket" the sealing surface is probably very corroded, again pointing to a full replacement. It's the option with the fewest questions.

Abracadabra

Couple of things:

1 - If you decide to take off that one section to replace o-rings and the first section, you'll end up finding that you'll have to replace the 2nd section as well since the face where the o-ring sits has been corroded as well. Remove the 2nd section and you'll see that the 3rd section is bad as well. That actually appears to be a pretty decent leak as the burner base has corroded pretty good. If you are lucky, you maybe get another year out of it and it dies at the end of the heating season. If you are unlucky it dies on you in the middle of winter on a 10 degree day.

2 - If and when you replace the boiler, make sure they replace that tee. The header is not supposed to be reduced like that until after it drops down to the equalizer. The way it is now, you have water sitting in the header creating wet steam. The tee should be full-sized and not reduced in the run.

I noticed a contractor's tag placed on the boiler. You must be in Chicago. Did they install that boiler or did they just service it? I'd be surprised if they installed it, because they are usually pretty good with near boiler piping.

ChrisL

Thanks for all the advice. Yes, I am now also figuring replacement is in the cards. I did check the chimney, and there is not any steam coming out like you would expect if it was being sent up the chimney, but with a 50' chimney, perhaps its condensing somewhat. I will look at the base of the chimney cleanout next for any moisture.

I like the idea of two smaller boilers, and will look into that possibility. There are actually two steam supply loops, each supplying a part of the building with a different exposure, so I would probably separate them, and run a boiler for each. Might be a more efficient approach than staging it in this situation. Looks like I will have to get the radiator measurments/edr.

Yes, it was an install by the labelled contractor. I'm in Skokie. Before my time, but I am told it was a rush install as weather was getting colder when the old one dry fired and cracked. Anyway, there is another issue with the piping I don't like, as the first supply loop comes off the header with a tee, and then second supply with an elbow.

Thanks,

ChrisL

vaporvac

The advantage of staging is the efficiency gained by cutting out one of the boilers entirely once the piping is hot and using only one boiler to begin with if there's a small temp differential. Not to mention redundancy. You eliminate all of these advantages by separating the loops.

Abracadabra

Also, if you try to feed each loop with seperate boilers you'll need to ensure each return is piped seperately. I wouldn't do seperate boilers for each loop. JMHO.

ChrisL

Good points. The problem I have with this building is its L-shaped, with different wind exposures. I get 4-5 degree variations in temperature in windy situations, depending upon location. Its already piped with separate returns, and looks like it was built somewhat as two separate buildings but perhaps I'd be opening a whole new can of worms.

So a two boiler staged setup....sounds like a good plan.

Thanks,

ChrisL

Dave in QCA

To get better control in your building because of different exposures, you might consider using thermostatic radiator valves. Is this a 2 pipe or 1 pipe system?

As for the boiler, It hate to put a lot into the repair of a boiler that is 17 years old. I would replace it. If it were mine, I would consider a new LGB after confirming actual size needed, or an 80 series with a two stage burner. By the way, most of the LGB models come with a two stage ability, all you need is a vaporstat to control it. My preference is biased in favor of commercial equipment as opposed to a staged setup of smaller boilers. But, that is a result of my own project. I saw an immediate 30% reduction in gas use when going from an Pennco (IRC) atmospheric to a WM 680. Here are a couple of threads, if you're interested in reading.
https://www.facebook.com/search/str/weil-mclain louis p best/keywords_top
http://forum.heatinghelp.com/discussion/143629/new-boiler-at-the-best-mansion

ChrisL

Dave, thanks for the link...thats a great thread, and beautiful setup you've got. I am leaning towards the same setup myself at this time: WM 80 with power burner. I'm a little hesitant to go with two separate staged units in this situation, and the hi-lo fire of the power burner seems like a nice compromise.

My building is one pipe steam, and I have since been corrected in that the old existing WM Lgb is now 25 yrs. old. Replacement seems like the only choice.

Chris

Fred

Keep us posted on the progress and make them do it right!