Newbie looking for a new wood stove: firebrick vs. no firebrick? best manufacturers?

chemist44286 Posted By chemist44286, Oct 9, 2006 at 4:29 PM

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  1. jjbaer

    New Member

    Oct 24, 2006
    My advice on how to pick a stove: Cat vs non-cat is somewhat of a ruse (both work well) and this decision is secondary to the following concerns: 1) you have to live many years with whatever you choose so be happy with how it looks before you buy it, 2) choose one best suited to your room size/overall needs based on BTU's required and the ability to distribute heat throughout your house and 3) make sure it will fit into the location you want and have it professionally installed.

    Sizing tips: look at your energy consumed to heat your house in your coldest month and convert this to BTU's. Divide by the number of days in the month and divide again by 24 hrs. Then multiply this by about 0.9 to get a rough idea of the average number of BTU's required to heat your home per hour during your coldest month. Then, look at your room size as compared to your total house size and determine what fraction of the total BTU's required for the entire house can be put into the stove room and still be able to distribute elsewhere in your home without overheating the room the stove is located in.

    Example: you heat your home (70 F average) and your hot water, with natural gas and your Dec gas bill shows 200 CCF consumed. 200 CCF is 20,000 cubic feet of gas (there are 100 cubic feet per CCF). Assume your hot water consumes 15% of this so the other 85% (17,000 cubic feet) is consumed by your furnace for heating your home. Each cubic foot of natural gas has about 1,000 BTU's in it so 17,000 cubic feet is 17,000,000 BTU's consumed in Dec. Divide this by 30 days in Dec and again by 24 hrs in a day and you get 23,611 BTU's of gas consumed (at the furnace burner) each hour to heat your home. Now multiply this by about 0.9 because only about 90% of this heat is delivered through your duct work to your rooms with the rest being vented to the outside via exhaust. This gives about 21,249 BTU's per hour being required to heat your home to 70 F. NOTE: this 90% figure assumes you have a high efficiency furnace.

    Now let's say your home is 1600 sq ft in size and the room you want to put this stove in is 300 sq ft. If 21,249 BTU's are required to heat your entire 1,600 sq ft home, then the BTU's required for this 300 sq ft room are only 300/1600 times the 21,249. That is, only 3,984 BTU's are required to heat this room! This surprises most people because they think in terms of 40,000 BTU/hr and larger stoves when in fact, for this example, only about 4,000 BTU's are required to maintain this room at 70F.

    So, if you need to heat your entire home, you need 21,249 BTU/hr on average output from your wood stove and if you don't want to overfire your stove, on average you're looking at needing approximately a 50,000 BTU/hr stove so that your average output is about 23,000 BTU/hr or so (which is approximately your heating requirement of about 21,000).

    Now that hard part: you need to decide that if you put significantly more BTU's into this room than the 4,000 BTU's/hr calculated, will you be able to distribute these added BTU's to other rooms in your house without significantly overheating the stove room? You can do this by turning on the circulating fan on your furnace or by natural convection if you have an "open design" in your home or by using a blower motor on your stove, etc. or you may simply pour more BTU's into this room, thus elevating it above 70F and hope that residual heat is distributed to other rooms. This is where the "trial and error" comes into play and hopefully you find the happy median where your stove room is warm, but not too warm while maximizing the warmth of the other rooms.

    hope this helps
  2. BrotherBart

    BrotherBart LLC Mid-Atlantic Division
    Staff Member

    Nov 18, 2005
    Northern Virginia
    I agree with castiron. Do all of the calculations, the research and talk to all of the dealers.

    Then buy the one your wife liked in the first place.
  3. Sandor

    Minister of Fire

    Dec 9, 2005
    Damn BB, that was good!
  4. BlastXng

    New Member

    Nov 21, 2006
    No Kidding.. It will at least match some decorating idea that she has!

    Lee Trevino: "If you're caught on a golf course during a storm and are afraid of lightning, hold up a 1-iron. Not even God can hit a 1-iron."
  5. stoveguy2esw

    Minister of Fire

    Nov 14, 2006
    madison hgts. va
    i'll try to shed a little light on the "BTU disparity between cat and non-cat units, for starters, if you look closely small firebox epa rated stove appear to have a higher btu test output than large box units in a lot of cases, this is because of the test charge used . in epa emmissions testing a 15 lb charge of douglas fir dried to a certain moisture content is used REGARDLESS OF FIREBOX SIZE. this is an important detail as a 3 cubic foot firebox will obviously take more wood than that , but the test has to have a "control" or common basis to test by. the btu output in a larger box unit which would take say, 40 to 50 lbs of wood for a normal "real world" firing would naturally emit higher amounts of heat than a small box unit. but , since the 15 lb charge is closer to the normal load in a small box, its going to give off a higher btu rating. but in real world terms it wont heat as large an area. therefore epa btu tested output ratings for large box stoves tend to be kinda low. this is especially true of catalytic units (im not sure of the physics on why , i just see the results). gram per hour emmissions and rated square footage in my humble opinion are more useful stats than epa btu for comparisons BB has just installed our 30- ncl large non cat rated up to 2200 square ft. i have burned our catalytic 24-ac rated at 2200 square ft in my home for 13 years. having seen both personally , i like the non cat because it is easier for the new to woodburning customer to operate , heat outputs are fairly similar in my opinion even though BB's stove came in at a higher epa output than my cat stove. burn times were also fairly close, his will hold a little longer because it is a larger capacity firebox. but in my mind the biggest advantage is ease of operation. as for durability in catalysts, the applied ceramics cat that came with my stove when i initially installed the unit is still operable with little if any degradation. this is after 13 years of use as a stand alone heat source in my one difference to be noted , my stove was listed at 2.6 gph and BB's came in at 1.63 gph. so his unit is actually burning more of the wood more completely than mine (of course mine is 1989 technology) his is newer technology and should be expected to be better in that respect. both types carry out the same basic function and both function well, they just do it differently, so in conclusion, my biggest thing with cat vs non cat is going to be ease of operation favoring the non-cat. throw out the epa btu data as it can be misleading and look at features such as firebox size, rated heating area (sq ft) and epa particulate matter emmissions (gpa) in my mind , these are more important

    i sure hope this helps cause it took 30 minutes and 3 beers time to type :)

    mike esw
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