Jotul 507 driving lessons

Hi Everyone,

Thanks to all who have helped me get the 507 running. Now that I've had a few days successful fire - I would like to pick everyone's brain on the nuances of this particular coal stove. I've been having a little trouble with the following:

- Reloading: getting quite a few puffbacks while trying to regulate the temps after loading. If I keep the stove above 600, its no problem, but I'm trying to keep the stove at lower temps. Is it even possible to reload and idle somewhere around 350? The manual is pretty vague about operation...

- You aren't supposed to load above the firebrick correct? Seems like there's more roam above the bricks where the burn plates are, but I feel like I read that in a previous thread about one owner making custom bricks to replace the burnplates in order to up capacity.

I feel like I'm forgetting something but for now I think those are the major issues I'm having so far. Thanks for any help you can give!

You should be able to top off at any temp. I open my MPD, slowly open loading door, yeah, yeah I've got a hopper--( back puffs is back puffs) AK, the only times I've had puff backs is when I first top off & close up the door to quickly--give it a bit to get the freshly created gasses out the pipe--close door slowly & then I close MPD--5 to 10 minute venture max--Yes, I also read about somebody raising those front bricks---AGAIN, I'd seriously consider getting a cap on that pipe

Will the 507 operate better with a MPD? The intake air seems very well controlled. Even the Hitzer factory on the 50-93 seems to say it's optional. Snowman seems to think that if you leave the top wheel open a turn methane will not accumulate. Does this make for a puff free life?

I see you are in Alaska are you burning sub-bituminous coal, bituminous, or anthracite?

Correct me if I'm wrong but the jotul 507 is a tall skinny stove like a potbelly.
A tall skinny firepot with bituminous is easy to cover all the fireover and allow coal gas to build up and poof insted of burning off as it forms.

Also how big is the coal you are using with bituminous you want to use large peices, I will get a puff back every time if I use coal smaller than about 2" and cover the fire compleatly.

AKShadow wrote:I read that in a previous thread about one owner making custom bricks to replace the burnplates in order to up capacity.

That other owner may have been me, but I didn't do it to increase capacity, I did it because the burn plates were trash & I was too cheap to buy new ones. That being said... at least with anthracite, you can fill it to the tippy top.... the fire never gets above the bricks.... On the other hand, maybe it did and that's what trashed the burn plates!

If you are burning bituminous, I don't know much about it, other than it does like air above the fire in addition to the air below the fire....but I don't know when that above air is introduced.

I am burning sub-bituminous, burns rather well really.

So am I correct then in puffbacks generally occur when the fire is cut-off by loading too fast, and then also not enough air while doing this? (sorry I know this seems like a question I should be asking through the search function

Finally someone who is also working with sub-bit.
i´m using briquettes, though! My experience so far: plenty of air - both over and under the fire - for the first 30-45mins of each fresh load. Allow for volatiles to burn off, add next load, repeat process. I repeat the process 2-3 times, 4lbs of coal at a time. Then I do almost shut off the primary air and leave the slider in the load door a tiny little bit open - and am good for 12-14hrs.
Don´t know about the specifications of the coal you´re burning, but the briquettes contain well over 30% volatiles. Those burn off with long yellow flames like a wood-fire, so I don´t (yet) dare to put in more than 4lbs at a time for fear of overheating the unit. I get really nasty smelling smoke coming out of the chimney if I put in more at atime and cut back the air while the volatiles are still burning off, but had no puff backs yet...

My thinking is that when you compleatly cover a coal bed you, cool the firebox temp by adding a large room temp. mass and you also cover the source of ignition over. So if you cover the fire over and open the secondary air vent you have set up a puffback because the tar and oil in the fresh coal that is against the red coals is outgassing and filling the stove with coalgas then once the firbox temp. gets back up hot enough to ignite the gas it goes poof and blows its self out and it does this many times intill it can stay lit.

The coalgas needs to burn as it comes off the coal insted of building up. I would try burning at least baseball sized coal and not covering the live bed compleatly so the gas comes off slower and can be hot enough to burn.

I've hand fed several tons of Alaska's subbitumionus C coal from Healy.
Add small amounts of coal to a hot fire, try to keep a flame though the added coal, this helps with the smoke and helps you recover the heat value in the gasses.
Check out the Usibelli coal data sheet: http://www.usibelli.com/Coal_data.php
Note the 29% water, I've added this coal to a warm fire and checked on it later and it was sweating and darn near putting the fire out.
Thank goodness it is low cost coal, I only used the larger size coal for hand fired, I'm not familliar with your stove.
I now have a underfeed stoker and I never see any smoke or strong smell.