mild winter = more creocote ??

[lopet]

Yesterday I cleaned out my owb ( maybe a few days too early with the cold snap we're having right now  ;D ) and i was stunned with all the build up I had in there. The " neck " from the firebox out to the chimney was almost completely plugged, surprised it was still drawing . I noticed this spring, that every time I opened the door there was more smoke coming out that way, but never thought it was that bad.  Because it's set up in a building I have limited reach from the back to use a long crow bar to chip away. So I ended up using a air chisel which worked pretty good but also spend about a hour and a half inside the box.  Man I have never seen it so bad.
Maybe I should mention that I only burn the wood I can't sell like poplar, cedar and hemlock . The only hardwood I have is end cuts from the processor and odd pieces. Does that have anything to do with it ?
Or did anyone else experienced some thing like that ?

[thecfarm]

What kind of OWB you got??

[lopet]

It's made in Manitoba and I think called Friesen built or some thing like that.  It's got a roughly 4x4x4 firebox and is a open system, if that's what you mean.  Is there anything specific about certain brands ?

[Ianab]

I can see how warmer weather and less demand for heat would cause the fire to run cooler, be dampered down and short of oxygen for more of the time. That would lead to more Creosote forming, compared to really cold periods when the fire is burning full heat most of the time.

[thecfarm]

4X4X4   Now that is what I need. Mine will take a 54 inch stick,but is only about 30 inches wide.
I have a heatmor. I have really no creosote. I don't even clean it. Just keep putting the wood in it. But I keep mine going all the time. I use it to heat my hot water. Not saying that is the best way to do it,but coming up the heat will go off and I will start burning some mighty small stuff. I just burn a bunch of junk all summer. In the winter it's hard to burn the small stuff unless I am working close to the house and can keep filling it.Which I have,but it does take time to fill it.4-5 times a day too.
I did not notice any difference in the way my operated all winter. And we had a warm winter too. I did noticed how long the wood lasted.
I have the old type OWB,not the gassier type. That might matter too.

[John Mc]

Species of wood has very little to do with creosote formation (contrary to popular myth). Burning green wood and/or burning a cold, smoldery fire is what forms creosote (assuming you have a properly designed system).

It's possible that the warmer weather meant keeping your OWB idling much of the time, contributing to the build up.

[lopet]

The wood I am burning is always dry but crappy and punky stuff . Sometimes probably not worth bringing it home  ;D, but I too like to have my woodlot cleaned up. I was guessing that the milder temperatures have caused the massive creosote build, as the fire didn't burn as hot as usual.
Just wondered if somebody has experienced something like that too, but you guys just confirmed that now. Will see how it is next year.

thecfarm   I think the box is even deeper than 4ft.  It's the largest model they had built in 2009 when I bought it. It was only $ 500 more than the second largest model, so I thought what the heck. Besides the house I'm also heating a 50x60 shop  and I only feed it twice a day. I normally only throw a certain amount of wood in depending on outside temperatures and heat demand.
When I come the next time, I hope the wood is gone and the boiler temperature is still at 130-140. It doesn't always work that way but close enough.
With yours running year around might be a different story but I am surprised you never had to scrape it out.
Know a couple of guys who have a heatmore and are happy with it.   

[thecfarm]

Had the heatmor since '07. I have never even thought about scrapping it. The first year I burned good dry wood in it,second year I experimented with green hardwood,cut it and burn it the same day. Than the next year I tried the white pine,cut and burn the same day. I was never cold,burned great,lots of heat, LOTS of smoke or steam. It burned ALOT of wood those 2 winters. BUT I wanted to see if it would do it. And it did. One winter I burned all cut offs from when I had my land logged and from pieces that I had left over when I was logging here too. I burned less wood from that dead pine than the green wood that I tried.I burn ALOT of dead wood and wood that others see and wonder how I keep warm. I have a friend that see some good hardwood in my pile and wonders where I got that from. ;D Very common to see dead cedar and fir in my wood pile. My dead white pines trees are kinda on the thin side now. I have chased them down and have burned them for heat. A white pine 18"-24" across has some wood in it.
I do usally let it burn down once a year and give it a good cleaning. There is a 4"X6" chamber that the smoke goes into at the front,than travels the lenght of the OWB and than goes out the chimney. That will build up with ashes.Than I clean out the fire box and that is it.
Mine will keep the temp. Very rarely will it get down to even 160°, 170 is low for me. I like the big firebox because it allow me to throw in crooked stuff of wood with a limb sticking out. I don't need to fill up every inch of that firebox.Even when I was gone for 14 hours I would still have a water temp of 180°. I use to have a indoor boiler at my other house. A whole diffeant set up. I use to have to choice my wood for a 14 hour burn. But that had about less than half the size fire box that I have now.

[svart ole]

First off I burn wood. Now I am going to say some things some may not want to hear. There are some issues with OWB's that you need to overcome. It all comes down to air fuel mix and heat load. You can load more fuel wood into them than they can burn in one heat cycle. And for the most part they don't provide enough combustion air. I do what I need to do to make sure I can provide enough combustion air. You toss in several hundred pounds of wood or more then it burns for a short time and shuts down and makes creosote deposits on cooler parts of the stove/stack. More of a problem in mild weather as the burn cycle is shorter. Only way I have been able to control it is less wood more often or more heat load that will give you longer hotter burns. Best way to add heat load other than opening doors and windows is more water storage. I know it is hard to not fill the firebox with wood once you have the door open and we want the fire to last all night but firing less more often will get you a clean burn. So will firing once a day and heating 1500 gallons of water to 180 degrees and coasting on that stored heat. Easy to say not so easy to do. I have two 500 gallon tanks I just have not found a place to put them. So in warmer weather I toss in less wood more often.  This old guy has to get up once or twice a night anyway. I am not fussy on wood I will burn anything and the lower btu punky stuff I burn in mild weather and save the round tamarack for the cold nights when there is snow cover.

[lopet]

This was the first year I actually had a problem with creosote and the only thing different last winter was that it was way warmer than usual.
Always try to get the right amount of wood tossed in so there is still warm air coming out of the ducts when the Mrs turns on the thermostat in the morning.     That just suits me fine. 
More water storage would be a advantage, but there is no room for it either. I can also see with forced air you can get a hotter burn, but unfortunately it's not set up for. I figured it's something less to have to worry about, if it just has a damper motor.
I think for the next season I am going to turn up the thermostat on the boiler to 180. So far the damper closed at about 165 and opened at around 140.

[thecfarm]

I have no idea how your OWB settings should be,but my blowers come on about 175 and off at 190. I have no idea,but that might be part of your creosote problem,not hot enough.

[John Mc]

For water storage, some folks around here bury their tanks. If you get them deep enough, you don;t have to worry about them freezing. I suppose you could also insulate the tank - perhaps with some of that spray foam insulation, if it would stand up to being buried?