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Mod-con venting beyond 100 feet?

JohnNY Member Posts: 2,623
Hello all,

I'm looking for a mod-con that can vent more than 100 feet to install in a New York City apartment building.

Anything come to mind?

Thanks for your help,

Contact John "JohnNY" Cataneo, Master Plumber
in New York
in New Jersey
for Consulting Work
or take his class.


  • Jeff W_2
    Jeff W_2 Member Posts: 57
    +200 ft vent

    This may or may not help you....the HTP Elite boiler can run a total of 200' (combined vent and air intake).   I guess this would only help you if it's possible to run a shorter length for the air intake so you can increase the vent length.  
  • JohnNY
    JohnNY Member Posts: 2,623
    This will do nicely.

    Thanks, Jeff W.

    Any other suggestions? I'll take 'em.
    Contact John "JohnNY" Cataneo, Master Plumber
    in New York
    in New Jersey
    for Consulting Work
    or take his class.
  • Paul Fredricks_3
    Paul Fredricks_3 Member Posts: 1,549

    I don't pretend to know much about Mod Cons, but it seems to me that the total length (intake and exhaust) are based on friction. So if you over size the air intake you should be able to get away with a longer exhaust. I'd imagine there's no module in the unit that can detect the actual length of the intake, so if it's oversized the unit can breath just fine.

  • JohnNY
    JohnNY Member Posts: 2,623
    (see rant included) I agree, Paul...

    ...but to get a sign-off from the building department, the manufacturer would have to list that info in the manual as a tested and approved venting method, which makes work for them that may never happen.

    And more to that point, there are lots of ways to make a boiler do things in the field that aren't listed in the manual, but everyone at the factory runs screaming when you suggest some of it...

    I recently wanted to convert a Lochinvar boiler from standing pilot to spark ignition using the factory parts listed in the breakdown for the 1-year old boiler in its manual.

    It would've been a simple conversion, and I could've made money and kept a client happy, but 2 tech support agents I spoke to condemned the thought of it saying "Lochinvar has no protocol for such a practice and will no longer support the product."

    Really? I'm swapping out a gas valve and pilot assembly, adding an ignition module and you're running away from the boiler?

    I guess it's all for the greater good, but give a professional in the field some credit, bro!

    (end rant)
    Contact John "JohnNY" Cataneo, Master Plumber
    in New York
    in New Jersey
    for Consulting Work
    or take his class.
  • TMorg
    TMorg Member Posts: 23

    Peerless Purefire is also 200' combined. They also have approval to draw inside air.
  • Henry
    Henry Member Posts: 979
    Over 100

    Some mod/con are aprooved catogory 2, therefore you may combine vents and easily exceed 100 feet. Otherwise the only two that will allow over 100 feet are the De Dietrich and Camus. I personaly would stay away from the Camus.


  • eluv8
    eluv8 Member Posts: 174
    edited May 2010
    Modcon venting over 100 ft

    If you can get a Hamilton Engineering Boiler in your area, call them up and give them the size of the boiler needed, distances you need it vented and fittings to get there. They will tell you what you will need to do to get there. The factory is very helpful and will also tell you if there is a wholesaler or rep near you.

    Purefire is another great option if you can pull room air.
  • Jean-David Beyer
    Jean-David Beyer Member Posts: 2,665
    I am a customer, not a contractor.

    For my W-M Ultra 3, the installation manual specifies several ways to install the air intake and exhaust piping. Roughly speaking, they require the air intake and exhaust to be in the range of 12 inches to 15 inches apart vertically; horizontally the separation is only a very few inches (the two pipes go through a "termination plate"). They do require the geometry to be such as to reduce the likelihood of the intake pipe inhaling the exhaust. (It is only slightly different when using their "sidewall vent/air termination plate" or their 3-inch PVC concentric termination; in these cases, the exhaust blows straight out from the wall and the air intake comes in from the side.)

    This seems to be because they want the pressure difference across the two pipes to be low even when there is wind blowing or gusting (sort-of like the closely spaced Ts in a primary-secondary piping system). For this boiler, I would guess that this would result in nearly equal lengths of the the intake and exhaust.
  • Paul Fredricks_3
    Paul Fredricks_3 Member Posts: 1,549

    I hear you John, I was thinking. That doesn't always sit well with the factories.

    I had a gas fired water heater the other day. This particular tank is available at 2 firing rates. The only difference is the burner. I asked the manufacturer if I could order the other burner and swap them out. He said that would void the warranty and they would not support the unit.

  • Slimpickins
    Slimpickins Member Posts: 323
    IBC boiler

    I recall reading about the IBC boiler made in Canada being able to vent up to 240'.

    From what I've read, it seems like an impressive boiler. Has anyone had any experience with these units?
  • Jed_2
    Jed_2 Member Posts: 781

    Check out the Smith's GC160 (Embassy Onex). Separated venting, 300 Ft.


  • CMadatMe
    CMadatMe Member Posts: 3,066
    edited May 2010
    What size boiler?

    Can't answer the question without knowing that. Attached is a Viessmann Vitodens Complete Venting Manual for the new Vitodens 100 and 200. All the info you is in there. Remember with this boiler you can hy-brid vent, heck you can take fresh air from the room if you have enough. I am assuming you mean 100' combined. Page 57 of the the pdf file. 3" cpvc can go well beyond the 100'. Again this is depdent on which boiler.

    Vitodens 100 WB1B10-26 & WB1B10-35

    Horizontally or vertically I can go out 118 combined feet with 1 pipe coaxial.

    Horizontally or vertically I can go out 164' combined w/ 3" z-vent or 200' w/4" z-vent.

    Horizontally or vertically I can go out 164' combined w/ 3" cpvc or 200' w/4" cpvc.

    Vitodens 200 WB2B

    WB2B-19, WB2B-26, WB2B-35

    I can go 115' combined with 2" CPVC

    I can go 148' combined with 3" CPVC

    I can go 180' combined with 4" CPVC
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • SpeyFitter
    SpeyFitter Member Posts: 422
    IBC - 240'

    The IBC VFC 45-225 (modulates from 45,000 to 225,000) can vent up to 240' and that's 240' on the intake, and 240' on the exhaust, but you can't add length to one, if the other is shorter if you get my drift.
    Class 'A' Gas Fitter - Certified Hydronic Systems Designer - Journeyman Plumber
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