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Drill holes through Majestic Thulman?

Post in 'It's a Gas!' started by Novicaine, Oct 26, 2013.

  1. Novicaine

    Novicaine New Member

    Joined:
    Oct 26, 2013
    Messages:
    7
    Loc:
    Fairbury, IL
    Hi all, I was googleing for info, and I kept seeing this forum come up so I figured I'd ask you guys. Apologies for joining and posting just for my one question!!

    My house is a ranch-style built in 1970. The fireplace is cement block/brick and is 6' wide all the way from the basement to the chimney cap. It has two flues, one with the fireplace, a Majestic Thulman Model L36A, which is double or triple wall construction. Near the top of the chimney there are intake vents in the side and if you look in them you can see that the outer ~8-10" pipe terminates there so it can suck air from the vents. The inner ~6-8" pipe exits the top. The other flu used to be used for the furnace, but that has gotten replaced and now vents horizontally with PVC. The water heater does still use that flu though.
    The guy who built the house must have used the gas log for about 1 hr, and then I did too, because everything is still shiny and new inside the chimney pipe. There was no point burning it because all the heat went straight up the chimney. Worthless.

    So... I decided to install a gas insert so we could enjoy some warmth from the fireplace... which I know nothing about, so I called an expert. I looked in the local yellow pages, called the one guy listed under fireplaces/chimney-cleaning and bought from him what he recommended: An Enviro E20 with sealed 2" and 3" intake and exhaust tubes that'll run up the old chimney. I was hoping he'd install it but he doesn't, but he says local plumbers can or I could DIY it (I've installed shop heaters and in floor hydronic boilers a couple times).

    Anyway, I have the gas line coming in through the fireplace walls that was used for the fire log, and looking through the old PDF docs I found online for the Thulman install, it does say "there is a 1 1/2 inch knockout to run the gas line through". But only 1.

    BUT... I also need electricity. So somehow I need to get an outlet or some metal jacket wire coming in... I assume drilling a hole through the side of the 2 or 3 wall metal original "insert" wouldn't be recommended. The new insert did come with a metal plaque I can rivet on that says "this fireplace no longer can be used it was modified for an insert blah blah.".

    I don't think there's room (or if it would be a good idea) to squeeze a power line in next to the gas line (which is flex copper).

    So... how do I get power in there? My first impulse is to drill through all the walls, stick piece of copper pipe that fits tightly to the hold in there with tabs bent over and rivet it to the tin. This way there won't be too much cross contamination of air (no more than the way the gas entry looks). The run the nm or whatever through that. Or the fireplace floor has some cheap-looking cement blocks -- maybe the floor isn't triple walled and I could drill through it?

    It seems such a waste, my old fireplace has a nice complex system for sucking in fresh air (from what I can tell) and here I am just running two new pipes up through it and not using any of that. It seems wrong.

    My next step on Monday just may be to call in the local plumbers.


    EDIT: I added some pics of the fireplace/chimney in question.

    Thoughts?
    IMG_4658.JPG IMG_4659.JPG IMG_4660.JPG IMG_4669.JPG Thanks in advance!
    Last edited: Oct 26, 2013

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  2. BrotherBart

    BrotherBart Hearth.com LLC Mid-Atlantic Division Staff Member

    Joined:
    Nov 18, 2005
    Messages:
    29,147
    Loc:
    Northern Virginia
    Welcome. One question or a hundred. What the place is here for. I am moving this to the gas room where more experience with this should be available.
  3. Novicaine

    Novicaine New Member

    Joined:
    Oct 26, 2013
    Messages:
    7
    Loc:
    Fairbury, IL
    Ok, thanks!!
  4. DAKSY

    DAKSY Patriot Guard Rider Staff Member

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    5,399
    Loc:
    Averill Park, NY, on Burden Lake II...
    No room to snake a 14-2 bx (armored) cable thru the same hole as the gas line? That's what I'd try to do. Then again & if you can't run both lines together, I wouldn't hesitate to put another hole thru the double wall at the same location on the opposite side of the firebox. I'd zipscrew a metal junction box to the rear floor of the firebox to use for your AC power source.
  5. Novicaine

    Novicaine New Member

    Joined:
    Oct 26, 2013
    Messages:
    7
    Loc:
    Fairbury, IL
    Ok, I have power!

    I ended up duplicating the hole for the gas line on the other side.
    - I drilled through all 3 layers/walls of the steel fireplace.
    - I ran a shielded power cable through the hole
    - I slipped a rolled up piece of flashing like a sheath around the cable through the hole, then let it expand to create sort of a tunnel for the power cable and to prevent as much air flow as possible between the 3 layers, tabbed the end and fastened it to the inner layer (that's how the gas hole did it also, I just followed their lead).
    - I used sheet metal screws to fasten a metal box with a GFCI outlet to the wall.

    Attached is a picture.
    fireoutlet.jpg
  6. Novicaine

    Novicaine New Member

    Joined:
    Oct 26, 2013
    Messages:
    7
    Loc:
    Fairbury, IL
    Next up, I need to run the intake and exhaust pipes out. The problem is, if you look at the picture of my chimney cap, the metal cap that vents exhaust and sucks intake air included in my kit doesn't fit between the granite cap on my chimney.

    So my options are:
    1) Remove the granite cap permanently.
    2) Find a lower profile dual intake/outlet cap (no luck so far)
    3) Vent out just the exhaust with a simple small cap, and figure out a way to use the existing chimney and fireplace's fresh air intake as the fresh air intake for the insert.

    #1 is the easy option conceptually, but I'll have to deal with physical issues, such as making a cap for the newly exposed chimney top..
    #3 is my preferred option, but requires the most knowledge. I found the patent to how my existing fireplace works online:

    http://g.icodex.org/patents/US2821975

    Along with an image that shows the air flow...

    [​IMG]

    [​IMG]

    So I wonder if it is possible to tap into the "C" airflow and attach that to my insert's air intake port?


    Hmmm...
  7. DAKSY

    DAKSY Patriot Guard Rider Staff Member

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    Loc:
    Averill Park, NY, on Burden Lake II...
    If you can, remove the granite cap, install the correct & approved cap for the venting system. Then see if you can find matching brick & add a couple to each cap support stack, until it's high enough to clear the DV cap. Do not modify the cap or eliminate it from the install.
  8. Novicaine

    Novicaine New Member

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    Loc:
    Fairbury, IL
    I had someone come out with a large forklift and remove the granite chimney caps cleanly so I can replace them later if desired. That means this weekend I'll be hooking up the intake/exhaust tubes and gas line!
    DAKSY likes this.
  9. Novicaine

    Novicaine New Member

    Joined:
    Oct 26, 2013
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    Loc:
    Fairbury, IL
    I got it installed and firing up this weekend... It warms up our family room nicely, and this picture doesn't do the flame justice, it's a nice glowing orange flame. The wife is happy, she did not like our old 1972 gas log.

    On the outside I ended up removing the granite chimney cap and had a sheet metal cap made and will just put that on top of the chimney with "exposed" pipe caps. I'll post a pic of that when I finish it up in the next day or two hopefully.

    IMG_4752.JPG


    All in all, this was a fairly easy project in the execution, it's just that each step required lots of learning for me on how to do it right.
    Heatsource and DAKSY like this.
  10. DAKSY

    DAKSY Patriot Guard Rider Staff Member

    Joined:
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    Loc:
    Averill Park, NY, on Burden Lake II...
    Looks like a nice, clean install. Congrats on a job well done.
  11. Novicaine

    Novicaine New Member

    Joined:
    Oct 26, 2013
    Messages:
    7
    Loc:
    Fairbury, IL
    I finally got the steel cap put on the top of the chimney to protect the bricks from weather. Next summer I may paint it or do a more elaborate one with a "roof"

    Chimney before:

    IMG_4669.JPG

    Chimney after: (It looks so short now)


    IMG_4759.JPG

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