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Wood Furnace on Main Floor

Post in 'The Boiler Room - Wood Boilers and Furnaces' started by 04HemiRam2500, Jul 10, 2013.

  1. 04HemiRam2500

    04HemiRam2500 Feeling the Heat

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    I am looking at installing the englander furnace found at Home Depot. The problem is there is no where to put the furnace in my basement/garage because between the oil tanks, the wiring and plumbing there is no where to put a flue. So, I would like to put the englander on the main floor of my house, I am going to have a hearth base that meets all the clearances stated in the manual.

    My main problem is that the manual does not state any clearances for the hot air duct and I contacted the company and they have not helped me yet, in fact they told me to go to this site. I want to put it on the main floor, I will have a hot air outlet about two feet above the furnace, then I want to run a line 90 degrees into the wall and extend it about 12 feet to the other side of the house so it heats evenly. What is the code for clearances for the hot air plenum, of a furnace and can I put a heat vent on the hot air line above the furnace or will it get too hot?From what I have seen the clearances are usually six inches for the warm air duct but does this apply to all furnaces? Also, what do you think of my setup? Thanks.

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  2. mustash29

    mustash29 Feeling the Heat

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  3. pen

    pen There are some who call me...mod. Staff Member

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    It sounds like you aren't planning on much ductwork.

    If that's the case, what's keeping you from wanting to install a wood stove?
  4. hobbyheater

    hobbyheater Minister of Fire

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  5. laynes69

    laynes69 Minister of Fire

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    I believe If clearances are not specified in the manual, then duct clearances default to 18". I would caution running the ductwork into a wall. I think these furnaces are add-on's and not stand alone furnaces. They are meant to be installed into a plenum of the central furnace. If an outage occured, then high heat can build in the furnace. Probably the reason why they recommend black pipe for the first few feet of ductwork then galvanized after. Each furnace has different specs on clearances. Testing determines clearances and safety, so they vary.
  6. 04HemiRam2500

    04HemiRam2500 Feeling the Heat

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    I need to know what the codes say for the warm air duct clearances because the manual does not state them. The reason that I am installing completely new duct work, which really is not that much work, and not putting in a wood stove is because my house is 3000 square feet. Again, when I emailed the company they sent me here. Also, is there a problem with using this as a primary furnace instead of an add on and running the warm air ducts through the wall? Thanks all.
  7. begreen

    begreen Mooderator Staff Member

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    FYI, there are several wood stoves that can handle 3000 sq ft if the house floorplan is open and the woodstove placed somewhat centrally. However if the place is a drafty barn with 20 ft ceilings a furnace may work out better.

    I'm not sure if it is coded or not, but most of the good units spec out that the supply plenum have at least 12" rise off the furnace and that the supply duct be no closer than 6" to combustibles for the first 6 feet. This is the install diagram for a Caddy furnace. Click to enlarge.

    Caddy supply ducting.JPG
    heaterman likes this.
  8. heaterman

    heaterman Minister of Fire

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    6" clearance is correct for plenums and the first 6 feet off the plenum. Personal experience with forced air wood furnaces is that overheating is pretty common due to over firing and undersized or restrictive ductwork. I would highly recommend erring on the side of caution especially if installed in the living quarters.
    pen likes this.
  9. 04HemiRam2500

    04HemiRam2500 Feeling the Heat

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    I have alot of rooms and turns thoughout the house, I just can not see a wood stove heating this house by itself. Also, the price for the englander compared to a wood stove that size is a much better deal and I know the furnace will heat my house. As far as not heating myself out of the house does that me I need to load less in the furnace and just load it more often.


    Okay, so 6 inch clearance for all ductwork will be meeting the fire codes for sure. That is good. Also, at about 5 feet in one of the duct line can I put a vent on the side of the eight inch duct line as long as it is metal it is okay to do that correct? Lastly, I need to build a hearth base for it and how thick of concrete slabs would I need to put this on. Would one inch thick be fine for this furnace?

    Also, what I would like to do with the furnace in case of prolonged power outage, can you take the top jacket plate off of the furnace and cook on the actual stove part itself. I see that it has crews I just do not know if you can take it off? If I should post this on the englander thread let me know. Thanks again.
  10. 04HemiRam2500

    04HemiRam2500 Feeling the Heat

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    Thanks again for all the help, the only thing I need to know now is how thick I need to make the cement hearth base becaues the furnace is gong upstairs and you can not put it on the carpet. Bad!! What is the code for the thickness of the hearth base for a wood furnace is the only question I have left. Thanks again.
  11. begreen

    begreen Mooderator Staff Member

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    No code here, you need to satisfy the stove mfg. requirements for the hearth per the manual. If power outages are frequent consider using a generator.
  12. heaterman

    heaterman Minister of Fire

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    Be aware that a solid cement base will slow down but still transfer heat to the floor below. Saw a good example of that on a fire run a few years ago where the unfortunate homeowner had poured his own cement "pad" about 2" thick and then put ceramic tile on top. The stove (unidentifiable) was of the type that was enclosed on the base with no air movement under it to keep things cooled off.
    Air movement under the stove/furnace is key.
  13. 700renegade

    700renegade Member

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    My guess is he's thinking about how to use this in case of a SHTF survival mode situation.
    I have an old box stove sitting in my shed that I'm keeping for just that reason. If I had to, I could lug it down to the basement, plumb it into my oil furnace chimney and be making 'electricity free' heat in a few hours.
  14. 04HemiRam2500

    04HemiRam2500 Feeling the Heat

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    My other option was to just install the drolet mineral board micore-300 but I am not sure if the r value of 1.03 is enough for the wood furnace? See link for the board by drolet. Also, with this board can't I just leave it on the board I then would not need to do any mortar work correct? The problem is that the manua states the clearances for the hearth pad opf the furnace but they never state the r value.

    Amazon.com: Micore-300 Mineral Fiber Board 48" X 24", 4-Pack: Home & Kitchen
  15. begreen

    begreen Mooderator Staff Member

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    The manual spells it out - There is no protection required if your floor is constructed of a noncombustible material such as concrete. Cut out the carpet in the area where the furnace is planned and put in the required ember protecting hearth.This could be a sheet of cement board, metal or brick. .

    "A. Floor Protection
    There is no protection required if your floor is constructed of a
    noncombustible material such as concrete. If your floor is constructed of a
    combustible material such as hardwood, carpet or linoleum some type of
    floor protection will be required. When selecting the required floor
    protection it is important that you install a U.L. approved board. The
    approved floor protection should be placed underneath the furnace, and
    should be large enough to provide a minimum of 8” (8 inches) behind the
    unit, 8”(8 inches) on both sides, and 16” (16 inches) at the front door(s)
    location. It should also be placed underneath the chimney connector and
    extend at least 2” (2 inches) on either side of the chimney connector."
  16. begreen

    begreen Mooderator Staff Member

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    Have to ask, what kind of living room is this? Why are you not considering a wood stove instead?
    laynes69 likes this.
  17. laynes69

    laynes69 Minister of Fire

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    A single 8" duct isn't going to do much, unless it's ducted into the main plenum of the central furnace. With over 3,000 sqft, even then it would be pushing it. I'm 100% with begreen, if I wasn't placing a furnace in the basement to duct it correctly, I would install a large woodstove on the main floor. Especially considering the englander is a non-EPA unit, while there's many large stoves that are EPA certified. More heat, less wood and a much cleaner chimney. With your home, you should have a large woodfurnace with a large plenum opening and a good sized blower. If you can't go that route, and nothing is going into the basement, then a woodstove would be a better option in my opinion.
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  18. 04HemiRam2500

    04HemiRam2500 Feeling the Heat

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    Okay so my original logic was that the furnace can take the small fire going and spread it across the house. Meanwhile, the wood stove would have to have a large fire in order to spread it across the house. Thus, I thought that the wood furnace wood be more efficient than a stove. I am currently debating between the englander furnace and the englander 22000 square foot stove. I have heard to stay away from the us stove brand.
  19. laynes69

    laynes69 Minister of Fire

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    A small fire = little heat. Whether it's a furnace or a stove. The difference between a non EPA unit and a EPA unit is, one when turned down will produce little heat and alot of creosote (non), while the other one once hot when turned down will burn that smoke, produce more heat and a longer cleaner burn. Technically to burn clean in the woodfurnace, you will need a hotter fire to burn off the smoke, resulting in lower burn times and more wood. There's a big difference between a non EPA and EPA unit. I don't feel what your wanting to do with the woodfurnace is a safe option, but that's me. I've had our ductwork in the old wood furnace hot enough to cook an egg. It's not a good feeling.
  20. begreen

    begreen Mooderator Staff Member

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    You are going to have more control over the heat and burn a lot less fuel with an Englander 30NC. If you want less heat, burn a half-load instead of a full load. If the house is warm enough let the fire go out. If not, feed it again with another partial load of 3-4 splits. Come winter when it gets cold you will be running full loads about 3 times a day.

    How open is the is the floor plan for the house? How is your current split and stacked wood supply? An EPA stove is going to want dry wood.

    PS: Note that the 30NC has stiffer hearth requirements, but nothing too hard.
  21. 04HemiRam2500

    04HemiRam2500 Feeling the Heat

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    I posted the rest of this read in the wood stove section about how I am going to try to make the englander stove work to heat my 2900 to almost 3000 square feet house. Please take a look. Thanks.
  22. 04HemiRam2500

    04HemiRam2500 Feeling the Heat

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    Sorry to go back to this thread however, a few of my family members are not to sure that they want a stove in the house for the following two reasons. The first is that we are afraid that the rooms near the stove we will be sweating in to heat up the large house which will happen. The second is that if someone falls near it or trips near it we don not want them to fall and get hurt or burnt. So, I am thinking furnace again sorry to change my mind.
  23. begreen

    begreen Mooderator Staff Member

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    #1 is not likely to happen with the cathedral ceiling and a fan blowing the cooler air from the main house into the addition. What is much more likely to happen is the family and pets all hang out around the stove in the winter. No one is going to cuddle up next to a furnace.

    #2 reason is just silly. You all are overthinking things. If worried about falling, better take out most of the furniture and mirrors then. A person can trip anywhere. Especially keep the family away from the stairs. Lots of accidents there. Many more than falling against stoves I am sure.

    If you want to do this right, remove the old wimpy, crumbling fireplace and install a new EPA fireplace that can be ducted to heat the entire place evenly.
    http://www.securitychimneys.com/pages/fireplace/high_BisTradition.asp?country=us

    PS: have you discussed the noise and ugliness of a furnace on the main floor?
  24. 04HemiRam2500

    04HemiRam2500 Feeling the Heat

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    I am thinking about putting the furnace in the garage but the best place to put it would be where the chimney would have to go through the side of the main area in the new edition. I was wondering if I could build something like a closet and hide the flue in it. Of course it will not be single wall pipe and I will have to meet clearances but can I do this?
  25. arbutus

    arbutus Feeling the Heat

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    It depends on your local mechanical codes. You need to make sure the adjoining room isn't a prohibited location, has sufficient volume, make sure the door has the right amount of clear area in the form of a hole, screen, or slats. If it is a prohibited location (bedroom?) you will likely need an exterior door to provide the air sealing required and take combustion air from outside the house.

    I moved our LP furnace from the entry way to a closet at our last house.
    I had to meet the required clearances, and the closet door had to have a certain percentage of clear area for ventilation.
    It was much noisier on the first floor than having it in a crawlspace, which is where it should have gone.


    We also had a wood stove. If I had a convenient place for a chimney I wouldn't hesitate to put one in.
    We raised two from infancy around that stove and never had a problem.
    They understand HOT, DO NOT TOUCH when they are able to crawl.

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