Fire grate in wood stove?

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bjorn773

Member
Sep 12, 2007
240
Rockford, Illinois
My stove manual says not to use a grate or elevate the fire in any way. That said, I have experimented with using one. Before you jump on me, hear my explanation. With out a grate, after a continuous burn all day and night I have an abundance of ash mixed with coals. While this does keep the stove warm and makes refiring quicker, it can be challenging to get the ash out. My particular stove has a removable brick in the floor that opens into an ash drawer. Separating the coals from the ash can be tough, or I waste all the coal as it drops into the drawer. If I suck the ash out with my ash vac, I end up with coal in the vac which are just fanned back to life from the rush of air past them. Then the vac gets very hot. With the grate, the wood burns on top and the fine ash falls below. When the fire dies out, all that is left is ash which means zero waste. Or if I have a nice bed of coals on top, I can tilt the grate up to suck the ash out from below. Just wondering if any other stoves have grates and if not, why?
 
I guess I just do not see the need for one. In the morning, I scoop what ash I can out, just a scoop or two, into a can and rekindle the fire with the coals. In your case, why not just scoop or push some coals over to the side and then remove ash via whatever method. You should be able to move the larger coals and some ash off to the side and then back to the front to add some wood?
 
I think it may cause an overfire situation because the wood is elevated and gets too much air? Probably the manufactures just covering their asses.
 
Or they may have had customers developing serious issues.

CTw has is correct. Just scoop out the ashes into a metal can or add a water trap to the ash vac setup.
 
There are a few reasons why you shouldn't use a grate in a stove that wasn't designed for one.

Basically all the reasons come down to one core theme: The stove was tested for both safety and emissions without the grate AND the manual says not to use a grate.

Plus personally I guess I just never saw the need.
 
And if you are having trouble getting our wood to burn without a grate, try piling your coals on either side of your stove and laying the fresh split across them. Tis what I do when I want a new log to catch fast.
 
Wow!, lots of grate responses! :p
 
My Jotul 7110 basically has a grate built in. The bottom of the stove is a cast iron grate, no firebrick on the bottom of my stove. I think the primary air is intended to keep it cooled. The primary air appears to enter through the grate coming in under the splits. Secondary air comes through the perforated tubes like usual, flowing from the back to the front.
 
This is what I do. I purchased a rake that looks like below for about $2.99 at K-Mart



http://www.clevedonaustralia.com/cart/images/CA-6190D_interchangeable-5-tooth-rake.jpg


When I go to load up a fire, I use that rake to push the coals to the back. I scoop out the front which is now only ash into an ash bucket, then move all that remaining stuff to the front to put it in the hottest part of the stove to burn on the next load. Load up and start a new fire, rinse and repeat each time I load.

*EDIT* that's neat, didn't realize if I put a picture link it goes into my post.
 
You can make one of those rakes like Roo did.Out of a hambuger turner. ;-)
 
I figured the responses I'd get would say what they did. The stove was tested without one and they must have a reason for it. I do have a rake similar to those pictured, the grate is just less hassle. I've been using the grate for the last couple years. A grate made from 5/8 steel rod will oxidize away to nothing over 2-3 months. I just had to replace a baffle at the top of the stove due to overfiring, perhaps my grate contributed. Mostly, as I found out from my previous posts, I was running the stove too hot without a thermometer. Thanks again for the input... this site truly is a wealth of information.
 
the century units are similar in design to our non-cats, one of the reasons for not having a grate stems from the instructions not to load the unit past the top of the bricks, its to allow the needed airspace to allow secondary combustion to occur. also , stoves designed to have the fire "on the bricks" have been designed to maximize the airflow to a fire at that level, raising the firewood up can change the way this airflow interacts with the wood fuel. causing a less efficient overall burn,the primary fire, even though it seems to start easier and burns initially better, doesnt react as well with the secondary burn and fuel gets wasted. best to "keep it on the bricks"
 
Thanks stoveguy. I appreciate the explanation and it does make a lot of sense. I removed the grate tonight before I lit the stove. Being similar in design to your non-cat, what stovetop temp do you recommend for this type of stove. Century's manual makes no mention of any specific temps. Since picking up my thermometer, I've been trying to keep it in the 500-650 range per recommendations from this site.
 
Some of the Morso and VC stoves have grates.

My technique for burning coals is to rake them into a pile in the middle just in front of the air supply, put splits on either side and two across the top. this creates a tunnel effect, and burns the coals completely. I typically remove ashes every from the stove, but I could easily go two days. If you think of the actual losses due to coals it's really minimal, but I thought of this once... If you put the coals through a peice of fine chicken wire or screening of some sort, after a winter, you'd probably have a nice amount of hardwood charcoal for your bbq in the summer. I might do that this year.
 
bjorn773 said:
Thanks stoveguy. I appreciate the explanation and it does make a lot of sense. I removed the grate tonight before I lit the stove. Being similar in design to your non-cat, what stovetop temp do you recommend for this type of stove. Century's manual makes no mention of any specific temps. Since picking up my thermometer, I've been trying to keep it in the 500-650 range per recommendations from this site.


that would probably be all right , have to check with the lab to see what temps are normally on the 13, ill check with corie and see if he can look em up
 
KeithO said:
My Jotul 7110 basically has a grate built in. The bottom of the stove is a cast iron grate, no firebrick on the bottom of my stove. I think the primary air is intended to keep it cooled. The primary air appears to enter through the grate coming in under the splits. Secondary air comes through the perforated tubes like usual, flowing from the back to the front.

Jotul 7110?
 
Warren said:
Some of the Morso and VC stoves have grates.

My technique for burning coals is to rake them into a pile in the middle just in front of the air supply, put splits on either side and two across the top. this creates a tunnel effect, and burns the coals completely. I typically remove ashes every from the stove, but I could easily go two days. If you think of the actual losses due to coals it's really minimal, but I thought of this once... If you put the coals through a peice of fine chicken wire or screening of some sort, after a winter, you'd probably have a nice amount of hardwood charcoal for your bbq in the summer. I might do that this year.

Most Jotuls have ash grates as well. But the normally on these stoves, air does not feed from below the grate.
 
Warren, I did sift the coals out the first year I burned. I produced quite a bit of hardwood charcoal, which I used for the bbq. However, it was time consuming and not much fun in subzero weather. That was when I came up with the grate idea. But, like others stated, there is a reason why I should not do this. Oh well, just gotta perfect my coal raking/placement technique I guess.
 
Sorry, its a Morso of course.....

Backpack09 said:
KeithO said:
My Jotul 7110 basically has a grate built in. The bottom of the stove is a cast iron grate, no firebrick on the bottom of my stove. I think the primary air is intended to keep it cooled. The primary air appears to enter through the grate coming in under the splits. Secondary air comes through the perforated tubes like usual, flowing from the back to the front.

Jotul 7110?
 
Ok, those grates on the bottom are to let ash out. Air does not come into the stove through them.
 
bjorn773 said:
Thanks stoveguy. I appreciate the explanation and it does make a lot of sense. I removed the grate tonight before I lit the stove. Being similar in design to your non-cat, what stovetop temp do you recommend for this type of stove. Century's manual makes no mention of any specific temps. Since picking up my thermometer, I've been trying to keep it in the 500-650 range per recommendations from this site.

spoke with bob , who designed our 13-nc and he feels that 550-600 is ok providing the stove is built as heavy as the 13 is. im not sure of the steel thicknesses on the top of the CFM unit so im not going to say for sure "yeah thats fine" but thats the info i got when i asked.
 
I use a sifter to seperate out the charcoal from my ashes when I spread the ashes in the garden... I dump my ashes into one of two 20 gallon trash cans outside, and when the second can gets close to full I sift out the 1st can, so I know that what's in it is seriously cold and dead. I found I only had to do this once or twice a season, so it wasn't a big deal. (I also use some of the dead ashes for traction control / snow melting on walks) This was using the old smoke dragon that had no ash-pan and which was hard to totally separate the coals from the ashes. I don't know how much I'll get now that the Encore will be my primary stove.

The sifted out charcoal works great in the BBQ, though it's much smaller than the usual stuff, but it gives good flavor and lights pretty well. With the smoke dragon I'd get a little less than 5 gallons of charcoal for a 20 gallon can of ashes. Part of the reason I started sifting was that I didn't like to see that much wood getting wasted. (I'm cheap, what can I say...)

My Encore does have a grate in it, but it is just to let ash through into the ashpan, no air is supposed to come up through it, if it does the grate won't last as the stove is being seriously over fired. The manual quite explicitly warns against using any other sort of grate in it.

Gooserider
 
stoveguy2esw said:
bjorn773 said:
Thanks stoveguy. I appreciate the explanation and it does make a lot of sense. I removed the grate tonight before I lit the stove. Being similar in design to your non-cat, what stovetop temp do you recommend for this type of stove. Century's manual makes no mention of any specific temps. Since picking up my thermometer, I've been trying to keep it in the 500-650 range per recommendations from this site.

spoke with bob , who designed our 13-nc and he feels that 550-600 is ok providing the stove is built as heavy as the 13 is. im not sure of the steel thicknesses on the top of the CFM unit so im not going to say for sure "yeah thats fine" but thats the info i got when i asked.

The top plate and the body of the Century stoves are 3/16".
 
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