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condensation issue

Had my my Weil-Mclain oil fired boiler to gas last fall. (Boiler is used for heat & hot water) About the same time, I had the chimney reflashed as there appeared to be a leak in that area. Then "allegedly" developed a condensation issue. Had a stainless steel chimney liner installed. I still have what (to me) are roof leaks around the chimney. Roofer states flashing is fine & not the cause.

Can I still be having major condensation issues after installing the steel liner ?


  • Zman
    Zman Member Posts: 7,469

    What are your actual boiler operating temps?

    Is the chimney on the exterior?

    Is the problem worse in the Winter?
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • icesailor
    icesailor Member Posts: 7,265
    Chimney Leaks:

    Take photos of the chimney where it goes through the roof and the area it leaks. Post them here.

    If a homeowner has a leak, they often call a plumber first. Even if there aren't any pipes around where the water appears. Some plumbers are better at finding outside building leaks than the professionals that do buildings can.

    The second part of the leak equation is that if there is a leak and a roofer can't fix or find it, they will blame it on someone else. Like the Plumber or heater that did some blamable act.

    Some of us get very good at finding things that others don't want to take blame for.
  • j a_2
    j a_2 Member Posts: 1,801

    Inside or outside chimney?

    What type model # conversion gun?

    What kind of readings on your combustion report from installer on last check up?
  • condensation issue

    Carlin EZ burner model#98954FR3 installed in September 2013.  I have a center chimney.  Boiler also supplies my hot water, so it does run a little every day.  I have work order for installation for installation of gas burner, but no notations as to boiler operating temp.  It is due for annual service now.  I will make appt.  and also be sure to get boiler readings at that time.  I would say problem was worse in the winter, and now with cooler weather returning, I am noticing it more. 

    I had chimney reflashed in October 2013 as there were signs of a leak then.  Didn't go back in attic until January of 2014, and noticed the problem was still there.  Did some research & realized that a chimney liner should have been installed.  Had liner installed late January 2014.  After a month or so, I did not see any improvement in "leak", so I had roofer come check the flashing & he felt the flashing was fine....and I should call chimney guy.  I did...chimney guy says liner and raincap are fine.    I let it go thru the summer, thinking maybe it would get good and hot up there and finally dry everything out.  It never dried completely and now it's increasing again. (condensation from cooler weather?)The wet rafter in the photo does touch the chimney.  Is it sucking THAT much moisture from the bricks ?  And why are bricks even wet as liner was installed ?

     (sorry...unable to rotate left photo)
  • icesailor
    icesailor Member Posts: 7,265
    Chimney Leaks:

    IMO, those are chimney leaks that have nothing whatsoever to do with whatever is going on inside the chimney.

    Those are old soft Styles & Hart (S&H) type common bricks. When the chimney flasher did his thing, did he waterproof the chimney with waterproofing? Silicone like Thompson's Water Seal usually stops that. That water staining usually shows up worst on the side of the prevailing winds. The old waterproofing products had VOV's in them. Not it's all water based products. The VOC stuff worked well for a few years. I don't know about the new water based stuff. It often has to be done every 3 years or so.

    If the guy who re-flashed the chimney, didn't waterproof the chimney, he's doomed to failure. I've seen the same type staining on rood insides in many old houses with soft bricks. And they didn't have any flue gasses in them.

    Take some photos from outside showing the front and sides of the chimney.

    Is there a "Cricket" on the back?
  • icesailor
    icesailor Member Posts: 7,265
    edited September 2014
    More on leaks:

    I just looked again at the photos. Notice the side on view of the bricks. Notice a space between two horizontal joints. Someone did a sloppy job of tuckpointing the joints. That is a really old chimney with high lime and little Portland Cement sand mortar. Even if you dig out all the joints and tuckpoint all the exposed joints above the roof and flashings, the water will still be sucked into the bricks. That's why it needs to be water proofed. The gray joints are new and the white one is original.

    Still, post pictures from outside.

    Another thing. When you are up there, turn off your light source and look up at the chimney in the dark. You might see daylight through the flashings.

    I once went on a service call to someone I had never been to before to fix a toilet, The owner was all antsy. He said that he was waiting for a roofer to come and give him a price to replace the 5 year old roof that leaked and couldn't be stopped. No matter what was tried. It was a cathedral ceiling so it meant replacing part of the ceiling. I told him that when I was done fixing the toilet, I would like to look at his chimney and roof. When I was done, I went up into the attic. It has stains like the ones in the photo. I turned off my flashlight and I could see the sea gulls flying by through the spaces in the side flashings. I told that the new roof would solve his problems because they would tap the old flashings down when they got done with the new roof, but if they sealed it up so the water didn't drive in through the spaces, the leaks would stop. He hired someone else to fix the flashings and the problems stopped. The rains in New England Coastal shores come from the South-East, East and North East. The leaks usually face the East quadrant. It seldom rains from the South or West.
  • j a_2
    j a_2 Member Posts: 1,801
    First Off

    Why so long to realize you needed a chimney liner? Whats up with installer and why no combustion report left on site….Its important to have one…for many reasons….If chimney pro.says chimney liner and cap are good…Your problem lies in chimneyleakhelp.com….
  • SWEI
    SWEI Member Posts: 7,356
    Old bricks

    Plenty of those soft, low fired bricks around here.  Gotta be careful pairing Portland with lime -- they have rather different characteristics.
  • condensation issue

    answers to your questions & more questions from me

    there is a cricket up there. 

    When roof was replaced 10-12 yrs ago, the chimney above the roof was rebuilt.  Waterproofed ?  I don't know.

    Re:  chimney liner...when taking bids to install gas conversion burner...3 out of the 4 bids I received said I didn't need a chimney liner.  And these were/are "reputable" heating contractors.  I know, I know.  you can't trust anyone, anymore!

    Not able to get photos from roof right now.  I'm 74 and have NO business on a 2nd story roof !  When I get chimney waterproofed, I will ask him to take pix. 

    My question:  Is it economically feasible/ legal to remove the upper chimney, say from the attic floor up to the top, and replace with metal gas chimney, and thereby doing away with the brick problem?