Question about commercial steam boiler venting

RayWohlfarth

When you replacing a commercial steam boiler with a new one, do you install a chimney liner? We dont do the installations any more and just rep boilers. We are seeing one local designer stipulate that a chimney liner is required on all steam boiler changeouts and it really jacks the prices up. I can understand the logic when you replace a hydronic boiler but a new steam boiler is only a percent or two more efficient than an older one. 80-82% We never had an issue with this before. You can imagine the cost for this liner Thanks

Mad Dog_2

Happy New Year Ray. With the age & condition of these 100 year plus masonry chimneys,  it always a good idea to reline with a nice Stainless Steel insulated insert if possible. The Boiler install company almost always subs the chimney work out, So I would keep that out of their bid to even the playing field.  That bid should go out to Chimney companies.  Mad Dog 🐕 

clammy

I believe on a lot of commercial jobs it is overlooked and should not be being re building residential masonry chimney is costly enough image the cost for a large commercial chimney or just installing a new steel mild gauge chimney rated for a couple of mil Btu Mind boggling and let’s not forget some real combustion air w interlocks and dampers ,I think a lot of guys just brush it away outta sight outta mind until a smart state pressure vessel inspector or boiler safety inspector picks it off or other issue arise . I always state that a chimney certification is required and that a certified chimney inspection should be done by a chimney pro it’s a liability that I personally don’t want to be responsible for and smarter people then I made me see the light of there view and it made sense . You can’t do it all even if you can stick to what your profession is instead of trying to do it all and taking all the liability that comes w it and some times the extra stress .
Peace and good luck
Happy new year Clammy

Steamhead

At the very least, have a chimney company do an inspection. That way, if the chimney doesn't get re-lined and there is an issue down the road, it's on them rather than you.

RayWohlfarth

Thanks @Mad Dog_2 That makes sense
@clammy I like telling them they need a certificate Im going to borrow that
@Steamhead Thats so true. So many lawyers now
Gentlemen Thank you and I hope 2024 is a wonderful year for you

Mad Dog_2

Yes...everyone wants one person to deal with and everything wrapped up in a nice bow.  That's very doable when cost isn't an issue or everyone is quoting apples to apples. In most cases, asbestos abatement, chimney responsibility should be parsed out. Mad Dog 🐕 

EBEBRATT-Ed

It's really all about how much heat you put in the chimney versus what the old equipment did. Masonry chimneys have been around forever. With a clay liner they will last for years as long as they are not underfired. Outside chimney is a different issue.

leonz

Hello Ray,

happy new year, has the interior of the stack been looked at to see if it has a clay tile liner or fire brick as the first layer of brick on the inside diameter of the chimney?

ScottSecor

On almost every commercial steam boiler we install there is an interior chimney. Of these chimneys, almost every one is terracotta lined. To date, I cannot recall an inspector (town, state of insurance company) even mentioning the chimney. In other words, no real reason for concern...yet.

However, as many of you know, there are new government mandates that were/are/or will be soon on the books that may change things. For example, in the past twelve months we were told Weil McLain discontinued the atmospheric LGB light commercial boiler. Weil announced a replacement LGB (series 3) high efficiency model that basically required stainless steel venting (especially when used as a water boiler). This version was to be DOE compliant for 2023. Months later, we were informed we could still get the "old" version, series 2. Not sure what the future holds at this point.

With regard to chimneys with cast iron steam boilers with power burners, we've been pretty lucky to date. No issues with condensing, crumbling, etc. that I'm aware of. This may be due to the fact that steam boilers always reach operating temperature on every cycle (or they would not produce steam).

We have installed our share of chimney liners, made of aluminum and stainless steel. We have also done double wall stainless on many commercial condensing jobs, talk about expensive!!!

We still service many commercial steel and cast iron boilers with "stub vents" that only have about a fifteen foot total length of venting. As you know, there is no chimney - they simply vent through the roof and go about five or ten feet above the boiler room roof. In most cases these vents are all double wall.

retiredguy

Up until I retired in 2007 I never saw a commercial/industrial chimney inside or outside the building that was relined, and that includes the burning of solid, liquid and gaseous fuels of any type. After that date I have no experience.

Mad Dog_2

As long as a Legit chimney company signs off, your liability ends there.  Mad Dog 🐕 

RayWohlfarth

@Mad Dog_2 I agree with that
@EBEBRATT-Ed As you can see this is an outside chimney but it looks fantastic. I would never sign off on it.
@leonz I stepped away as the competitor who's sells boilers says that the liner is needed. I offered to sell them boilers and let them figure out the chimney
@ScottSecor Thanks Im glad I just sell the equipment LOL
@retiredguy I agree. We never talked about a liner when replacing a steamer with a steamer. Now, someone is interpreting the code as it is required. I should post a question to the code committee
Thank you all sirs. I appreciate it