Page 1 of 2 12 LastLast
Results 1 to 20 of 26

Thread: Fire but no heat

  1. #1
    New member reuben_j_cogburn's Avatar
    Join Date
    Apr 2006
    Location
    Alaska
    Posts
    285

    Default Fire but no heat

    I ran into an interesting situation. My landlord heats with wood. Not unusual but the woodstove does not get hot! It does get warm but barely heats the house. The stove looks okay as far as seals and everything goes. I replaced the damper in the stove pipe. The stove is made for an 8" pipe but is necked down to 6" just above the stove. Wood burned is typical birch and spruce.
    I'm no expert on anything but have never encountered a woodstove that wood be so cool with a good fire going.
    Manufacture is unknown but looks very typical. I offered to install a barrel stove I'm not using and block around it but the idea was shot down.
    Anyhow if anybody could tell me why a stove like this would burn so cool when everything (cept the downsized stovepipe) is in order?
    Inquiring minds want to know!


  2. #2
    Member
    Join Date
    Apr 2006
    Location
    Fairbanks
    Posts
    327

    Default

    How much wood are you burning in how much time? Is the wood seasoned? What are the flue temperatures?

    Sounds weird!

  3. #3
    Member
    Join Date
    Apr 2006
    Location
    Fairbanks
    Posts
    520

    Default

    I wonder if your stove is drawing as much as it should. Our garage stove is a newer, more effecient design. It takes a long time to heat up, but stays warm longer which, I understand, is inherant in the design of the newer stoves. It does seem as it could do a little better, however. The original stove had 8" pipe, but we joined the 6" pipe of the newer stove into the 8" about 5 or 6 feet above the stove. I've heard a stove pipe that's too wide will make the stove not draw well, I'm just wondering if there's any guidelines as to what is lost if a smaller pipe is joined to a larger one, and if it makes a difference how far up they're joined. Anyone else have any thoughts on this? Thanks....Louis

  4. #4

    Default

    might check the stove pipe. being necked down like that it will plug up faster then the 8" pipe. causing the air intake to be low and half smothering the fire and keeping it cool.

    does it smoke allot?

  5. #5
    Member
    Join Date
    Nov 2007
    Location
    Upriver, Alaska
    Posts
    32

    Default This n' that...

    Reuben

    Gun Runner on the other thread said his neighbor burns green wood and does not get a fire going... I very much take it that your landlord knows better than that

    Had a stove here "that smoked light hell" for no reason at all. Well not quite, what happened is a heavy snow load crushed the top end of the smoke stack shut. That was a quick fix.

    I had my stove replaced, went from a 6" stack to an 8" version, and kept the old system by doing what your buddy did. That was a bad choice, I could not open the stove without smoking the cabin out. Now it's all 8", what a difference!

    Now if the stack is clean, there should be no problem, right? At least in an ideal world

    Louis, the 8" stack is a must for bigger stoves, the draft will be fine by the time you are through the roof and have enough length on top, all double walled, cuts down on soot, besides safety.

    Ahhhhh, my stove is so wonderfully warm tonight, cooooozyyyyy, ahhhhh...

    Gord
    "He was a man of no patience, you could see it in him. That was a notch against him. In the wild country, a body needs patience".

  6. #6
    Member
    Join Date
    Oct 2007
    Location
    Eagle River, AK
    Posts
    124

    Default Things to concider

    Gordon Lightfoot makes some very good points, and misses just a tiny wee bit on a couple. I've taught combustion analysis to trade professionals for many years, and would offer the following:

    Never, ever, reduce the flue size of a heating appliance unless specifically called for by engineering guidelines based upon flue length, btu input, etc. Flue pipe size is proportional to combustion chamber dimensions which is related to heating capacity. Reduce your chimney pipe, and you reduce your heating capacity.

    Other people have made some other good points worth taking to heart here:
    The main chimney should be all-fuel-chimney, of the insulated variety rated for wood, coal, oil etc. ( Metalbestos SS, Duravent Duratech, Security, Excel, etc ). Not triple wall chimney which only utilizes air space between the walls to meet the safety rating for the pipe. That stuff is much cheaper, and fine for California, but not for cold climate areas such as Alaska. Try to keep the single wall vent connector ( the pipe from the appliance to the main chimney ) as short as reasonably possible. I recommend 6-10 ft max for vent connector on woodstoves.
    Using the double wall " reduced-clearance" connector pipe is even better, ( Duravent type DVL, Metalbestos type DS ) tho' it costs more than single wall 24ga galv. or black pipe. These will further retain more stack temp.

    The reason for all this is as someone alluded to in a prior post: keeping your "stack" temperature as high as possible. Higher stack temp= better draft. Better draft = hotter fire.
    Drilling a hole and measuring the stack temp in the single wall pipe will provide extremely valuable info. You need a special type high-temp thermometer to do that. Using the typical magnetic woodstove pipe thermometer would probably be good enough, however.

    Try the following: load the stove with what would be concidered a normal load, get it burning as good as it can, then check the stack temperature. If it's what we would concider LOW-- meaning 250-350 degrees F-- then you either don't have enough air for combustion ( are the air adjustments wide open? ), too small a chimney ( or too short ) , or you're burning wood with too much moisture content. Pay attention to the qty of smoke & soot ( carbon ) present in the chimney outlet. the smoke should clear after the flue pipe and stove warms up to steady-state.

    Soot & smoke is an indicator of incomplete combustion, and is usually due to insufficient air for combustion. Once a stove is warmed up and heating well, people will crank down the draft adjustment, slow the fire down, and get longer burn times. This does create more soot and creosote, but extends the combustion time of each fuel load of wood, and obviously tones down the volume of heat. But its a trade off-burning at higher stack temps is good for the stove and chimney, as you generate almost no creosote ( if using seasoned, dry wood ). But-- you use lots more wood. People that burn constantly with wood become experts at balancing this equation, simply thru trial and error.

    Conversely, if you have the opposite problem: really HIGH stack temp-- 600-800 degrees F ( or more ) -- and very little heat tranferred to the space- then all the heat is likely going up the flue. Sometimes this is due to too large of a chimney ( excessive draft ), wide open air adjustments. All of which can cause the heat to fly up and out the stove before heating the metal parts of the stove.

    This can also be due to a design flaw within the stove itself; or damaged or missing baffles within the woodstove. These baffles serve a very important function: they slow the flue gasses down and make them take longer paths thru the stove before exiting into the chimney, and thus transfer more heat to the stoves metal surfaces for heat exchange.
    If these are messed up, excessively high stack temps are a sure sign.

    Hopefully this gives enough info for you to start a more thorough investigation into individual aspects of your problem, and begin to zero in on specific areas, and eliminating others.

    Oh-- and as a general rule for comparision, a "typical" normal stack temperature for a woodstove is somewhere between 375-450 degrees.
    But- I'm the technical Nerd guy--- I would defer to other members here who burn wood regularly--- they are genuinely the best sources and experts for this info, as the good ones watch things carefully and constantly.

    Good luck your woodstove!

  7. #7
    Member
    Join Date
    Oct 2007
    Location
    Eagle River, AK
    Posts
    124

    Default PM me with details

    Reuben,
    It's ok to PM me with any specific questions as things progress, if you'd like.
    Good luck, Bill

  8. #8
    Member BucknRut's Avatar
    Join Date
    Sep 2006
    Location
    The BEGINNING of the road!
    Posts
    1,137

    Default Forget the PM!!

    We want to know the details too!

    Mr. Bill and others have filled your brain already. What no one has mentioned is how the stove has performed in the past? Have you asked your landlord? If it produced sufficient heat in the past, then you are dealing with a fix, rather than a replacement or restructuring of the system.

    If it worked before, the first things I would check would be the buildup in the stack. ESPECIALLY if you are burning BIRCH!! Burning that stuff is great for heat, but you really have to watch the buildup it produces. I check mine bi-monthly using a hand held mirror and flashlight.

    The second would be the baffles in the stove. The baffles should slow the escape of smoke/heat. These could be plugged, dirty or broken.

    If it is a newer, more efficient stove, you might try cracking the door to get the fire really blazing.

    ...my .02

  9. #9
    Member garnede's Avatar
    Join Date
    Sep 2007
    Location
    soon to be back in Alaska
    Posts
    1,214

    Default

    Is it possible that the house is sealed so tight that enough air is not getting to the fireplace?
    It ain't about the # of pounds of meat we bring back, nor about how much we spent to go do it. Its about seeing what no one else sees.

    http://wouldieatitagainfoodblog.blogspot.com/

  10. #10

    Default

    doubt it but it is possible

  11. #11
    Member BucknRut's Avatar
    Join Date
    Sep 2006
    Location
    The BEGINNING of the road!
    Posts
    1,137

    Default

    Quote Originally Posted by garnede View Post
    Is it possible that the house is sealed so tight that enough air is not getting to the fireplace?
    Not unless you are having a hard time sucking air yourself. Joking, but na, I doubt it.

  12. #12
    Member
    Join Date
    Oct 2007
    Location
    Eagle River, AK
    Posts
    124

    Default Well, Excussssssssssse....MEeeeeee......!

    BucknRut,
    Your input is EXACTLY the kind of dialogue I was hoping my response would create. You bring up an excellent point about the build up within the existing chimney itself. Since it's already improperly undersized, it's possible it may have actually run sufficiently in the very beginning, hovering on barely-capable. Now, with a bit of build up, it may wander into the area of even more severely undersized.

    Your comment about checking the baffle & flue passages for restriction: Exxxxx-cellent!

    My heart soars like a hawk...

    Now- what about you others?---- I know there are long standing wood users out there who should really weigh in. The Nerds should not dominate this conversation/solution. Practical sense and level thinking usually userps, exceeds ( and usually short-cuts ) the book knowledge...
    BucknRut, you actually inspect with a mirror... I think you certify for a genuine plastic pocket-protector

  13. #13

    Default

    I pointed out the stack issue in post #4

  14. #14
    Moderator bkmail's Avatar
    Join Date
    Apr 2006
    Location
    Palmer, AK.
    Posts
    4,120

    Default Replace the stove...

    Our house had an older model earth stove in it. It too would not provide sufficient heat as described above. Our solution was to replace it with a Blaze King Princess model. Best $2100- I have spent on the house.
    The new stove, (using the existing stack), is a ton better. We've been heating with the new stove for 3 years now and it has more than paid for itself.
    The difference is the old stove was worn out (I guess), would not draft, barely even warmed up (like not even hot to the touch), and scared the heck out of us a few times when we would open the door and it would take off.
    The old stove would also have a bunch of condensation built up on top of the pipe on the roof around the cap. Our new stove burns sooooo much cleaner and more efficient.
    BK

  15. #15
    Moderator Daveinthebush's Avatar
    Join Date
    Jul 2003
    Location
    Valdez, Alaska
    Posts
    4,402

    Default Couple of thoughts

    Fuel + air + combustion = keeping me warm

    If my air intake is blocked it will not draft correctly and the fire burns low, producing minimal heat and smoke back into the house.

    When I clean the stack, I have to remove the pipe and vacuum the top plate in the stove. As creosote hardens and falls off of the pipe, it accumulates on the plate in the stove. This will actually shut the stove down. I have a Drolet stove.

    The stack needs to be cleaned at least every other month. Completely, every section.

    Elbows + horizontal pipes = problems with creosote.

    If it isn't working properly, clean everything.

    Vietnam - June 70 - Feb. 72
    Cancer from Agent Orange - Aug. 25th 2012
    Cancer Survivor - Dec. 14th 2012

  16. #16
    Member BucknRut's Avatar
    Join Date
    Sep 2006
    Location
    The BEGINNING of the road!
    Posts
    1,137

    Default

    Quote Originally Posted by Daveinthebush View Post
    Fuel + air + combustion = keeping me warm

    If my air intake is blocked it will not draft correctly and the fire burns low, producing minimal heat and smoke back into the house.

    When I clean the stack, I have to remove the pipe and vacuum the top plate in the stove. As creosote hardens and falls off of the pipe, it accumulates on the plate in the stove. This will actually shut the stove down. I have a Drolet stove.

    The stack needs to be cleaned at least every other month. Completely, every section.

    Elbows + horizontal pipes = problems with creosote.

    If it isn't working properly, clean everything.
    Right on Dave...nicely said.
    Quote Originally Posted by Mr Bill View Post
    BucknRut, you actually inspect with a mirror... I think you certify for a genuine plastic pocket-protector
    YUP...before you get too excited, you should make sure the fire is out befor esticking your arms and head in there

  17. #17
    New member reuben_j_cogburn's Avatar
    Join Date
    Apr 2006
    Location
    Alaska
    Posts
    285

    Default update

    I'm having difficulty posting here for some reason. I'll try this one and if it works I'll post a real update...












  18. #18
    New member reuben_j_cogburn's Avatar
    Join Date
    Apr 2006
    Location
    Alaska
    Posts
    285

    Default real update

    Everything seems to check out okay.
    1) seasoned birch and spruce.
    2) new chimney stack.
    3) new damper.
    4) Stack downsized immediately above stove.
    5) stack goes straight up through the roof.
    6) Cabin is not built tight enough to cause a problem.

    I'm limiting my involvement to suggestions..... A new cabin is needed as much as a new stove.
    any fix that isn't possible with changing a proceedure or minor repair is out. Funds are not available...... I'm just trying help a bit without getting involved.

    ciao ya'll

  19. #19
    Member BucknRut's Avatar
    Join Date
    Sep 2006
    Location
    The BEGINNING of the road!
    Posts
    1,137

    Thumbs down Man...that's a stumper.

    I wish I had something good to tell you reuben I know you are looking for siggestions, but let me shoot a few more questions.

    1. Did you ever find out if the stove heated properly before?
    2. Are you able to get a roaring fire going in there?
    3. Does the chimney draw, as in really suck the air? Say if you crack the door a half inch, does the blaze just take off and pull? You should be able to see results and hear them.
    4. Is there a spark arrestor on the top? Is it clogged? My brother pitched some cardboard in the fire once and it plugged the stack at the top enough to slow down the draw.
    5. Is there a fan on the stove? Some stoves are designed with an air chamber connected to an electric fan to force air throughout the house.
    6. Is there a thermastat that adjusts the damper or air intake?

  20. #20
    Member
    Join Date
    Oct 2007
    Location
    Eagle River, AK
    Posts
    124

    Default 2 more suggestions

    I just reread your original post, and also now realize you are merely assisting, and $$ input into solution is out. So, I would offer the following:

    Assuming the stove has been inspected for all properly running parts: non-clogged air baffle passages, air adjustment shutter passages clear, etc.
    I recommend removing the 6" cast iron damper in the single wall pipe. These are used as a further air adjustment to slow down already good draft in the flue. They essencially "reduce" the total diameter of chimney avail for venting by the basic old "hourglass" bottleneck effect. But- in this case the chimney is already too small to begin with. The damper just further agravates the situation, serving no positive purpose whatsoever. Use the air adjustments on the stove itself.

    As someone stated earlier, crack the fire door open a bit, if need be, to get more air for a fuller fire. Of course, if smoke billows out the crack like crazy, scratch that one... And that would be a sure sign the draft & chimney's likely the issue.

    One more thing worth checking: make sure the firebox is not too full of ashes. If the ash is too high in the firebox, it may be actually above ( and clogging) some air intake holes that are sometimes common around the side and rear perameter of the firebox. You don't want all the ash removed, as it provides a safe base for the burning wood, remove just enough to get the air holes clear by an inch or so.

    You also imply in you original post that the fire seems to burn fine inside, yet not much heat is radiated to the space. The stack temp info would provide a very important clue here, and is one thing you should stress strongly that he check, even with one of those inexpensive magnetic kind.

    But- I suspect the fire isn't burning to the level that it should, especially once you close the door.

Page 1 of 2 12 LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •