Jotul f100 - can I burn in bottom chamber - and other new user questions

[tbb2]

I have a new Jotul f100 and have been burning it for the last several months this winter.

First Question:
Maybe from lack of experience, but I find keeping the stove hot (over 400 degrees), is a challenge in as much as I am stoking it with 2 pieces of wood every 30 minutes (the recommended 3" max dimension).

At that rate coal and ash build up and start coming out onto the hearth without much encouragement. I assume that everyone has to clean out this stove once a day to remove the ash build up (?).

There is a bottom cast iron chamber in the stove that I think has something to do with a European coal burning kit and ash pan.

Is it possible to remove the bottom "burn" plate and load wood in to the bottom chamber and also remove the ash lip (exposing all the glass and stop creosote build up on the glass behind the ash lip) so I can get more wood into the stove and drop the level of ash so it does not come out onto the hearth so much? I'm up to building an ash grate to sit in the bottom chamber.

I have the stove fully inserted into an existing brick fireplace with a fire brick floor and am not concerned about floor temperatures. Right now with 400+ degrees reading on the top plate thermometer it is cool under the stove.

Second Question:
It strikes me as odd that I can't get within two feet of the front of the stove with the door open - while loading it - without my hair starting to burn - yet the stove just keeps up with heat lose from my living room (say 1/4 of the house) when the temperature outside is in the mid 20s. The heat lose in my entire 1260 GSF house is about 25K btuh at 30 degrees outside (I have calculated it and confirmed it clocking my furnace when replacing my house gas furnace). I installed an insulated cover plate around the chimney liner at the level of the old damper so hot air isn't just going up and heating the inside of the chimney. I strikes me that a lot of heat must be going up the chimney (?) or has inserting this stove in the brick alcove made that much difference in how air circulates around it and into the room?

I have played a bit with a house fan pulling air across the front of the fireplace and it shows a substantial difference which is why I suspect the brick niche. It does not take much for the fan to drop the stove temperature 50 - 100 degrees. This puts me back at keeping wood in the stove to keep it hot.

 

[fishingpol]

Welcome tbb. I'll start off on this thread.

No doubt the F100 is not the biggest stove out there, but it fits my needs well for the set up in my house. Typically I burn 2-3 splits at a time and have stove top temps of 500-550 without any issue. I am using wood that is just under 20% moisture content. I have my stove in a fireplace also, rear vented with a tee connected to a 25 ft 5.5" stainless insulated liner. It sits maybe 2/3rd's of the way in the fireplace. On any given day, it will heat my 1,200 sq ft house without a problem. I do have all new windows, and thanks to an energy audit, a bit more insulation. I add a split or 2 every hour or so. (yes, tedious, but it is the nature of the beast or not quite a beast).

There was a recent post of the bottom plate removal, and yes it is for multi-fuel burning. I would not burn in the bottom with the plate removed. There is a small air inlet on the bottom that can be used when burning coal using the grates. It is secured closed with a screw.

I have a sheet metal block off plate, I was not able to insulate above it due to space limitations, but I did seal the perimeter with firecaulking. I also wrapped a piece of liner insulation around the liner where it goes up through the plate, and secured that with a screw clamp to keep it snug. Doing this, I have noticed a lot more heat kept in the house and not up the chimney.

It is a nice little heater and is no slouch on the heat output for its' size. One thing I have found is that I always need a nice coal bed, and I rake the coals around before adding another split. I clean the ash out about every 2-3 weeks. The liner has helped wood burn down better with less ash. I burn mostly oak, maple, cherry and locust. Hope this helps.

 

[begreen]

Welcome tbb. If there isn't a lower block-off plate, you are probably losing a fair amount of heat into the masonry of the chimney. If this is an exterior fireplace chimney, make that a lot of heat. If you can bring the stove forward and extend the hearth, that will also help. Otherwise, add a lintel level block-off plate if possible to keep more heat in the room.

That said, it sounds you have too small a stove for the job unless you like stoking it like a fireman.

 

[tbb2]

fishpol:

You say -
" I would not burn in the bottom with the plate removed. "

Do you have any specific reasons for your aversion?
Seems if I fabricated a grate and went through the curing process, using the bottom chamber would solve the problem of coals and ash flowing over the curb and out the door for a number of days. - Yes I know the stove is not safety tested for this operation but I do have it in a fireplace so the floor is not going to burn.

-------------------

After some seasons of use I am finding what size wood works best for starting and sustaining, how to build a hot fast fire for start-up, that there is difference in coals depending on wood species, and that keeping an air path clear from front bottom under the wood and up the back makes a huge divergence in heat output. There is room for a new product to act as a grate.

The bottom of the chimney was blocked off and insulated to begin with. I still wonder if a secondary baffle in the flue would have been a benefit.

The amount of heat soaked up in the surrounding masonry substantial. I finally got around to trying to burning the stove through the night and found that even though the stove temp drops down to 100 to 200 that makes a big difference in morning start-up. The surrounding masonry is kept warm through the night and morning heat output is faster.

I think it is safe to say that this little stove is a miniature furnace with the benefit of a viewing glass to enjoy the flame. It is not just a modification of an open fireplace ... something on the order of traveling by foot or riding a bike.