Hot metal smell - Roxul?

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It should go away soon. Perhaps you are smelling dust that got knocked down on the insert and is getting heated up? Or dust on the inside of the convection chamber of the insert that settled on top of the firebox as the block-off plate was installed?

All of those are possible. Who knows. I definitely did not go through and clean the firebox with a fine comb after the plate was installed so there certainly is dust and debris from the impact of drilling into the brick to pre tap the Tapcons.

Ultimately it’s ok to have the mineral wool insulated against the insert though?
 
Yes
 

Ok good! Thanks as always.

As long as the wife and girls are safe, the smell is no big deal :)

I can already tell that there is a lot more heat staying in the house. There is a lot of heat pouring out from around the decorative surround given it isn’t sealed to the hearth. Heat that used to be flowing right up the chimney.
 
Did you put the insulation on just the sides and rear or also on the top of the insert?
 
Did you put the insulation on just the sides and rear or also on the top of the insert?

I insulated the top of the block off plate prior to install. Once i did that, I stuffed as much mineral wool as i could on all exposed sides of the insert. Rear, top and both sides.

Good or bad?
 
OK, I haven't any experience with it being on top of the insert. Just sides and rear. It could be the dust in the convection chamber is reaching new high temps? Just speculating.
 
OK, I haven't any experience with it being on top of the insert. Just sides and rear. It could be the dust in the convection chamber is reaching new high temps? Just speculating.

New high temps meaning temperatures that it hasn’t seen before due to the lack of ability to do so prior to insulating? Basically, the insert is getting hotter than its “used to” due to the addition of the plate and insulation?

The idea being I’m burning off some “gunk” and it smells....maybe?
 
How many fires have you had in it since installing the Roxul?

Also please keep us updated as to if/when/how you get the smell to go away. Not sure I'll be able to burn much for a week or two. Maybe a fire tomorrow but it's ngoing to be too cold to keep the windows wide open again.
 
Howamy fires have you had in it since installing the Roxul?

Also please keep us updated as to if/when/how you get the smell to go away. Not sure I'll be able to burn much for a week or two. Maybe a fire tomorrow but it's ngoing to be too cold to keep the windows wide open again.


First fire was tonight. Both for the season and after the block off plate.
 
I didn't have any odor from my roxul. I have it insulating my fireplace, and stuffed above the block off. I used the Safe-N-Sound from before they renamed the product (it's "Rockwool" now, not Roxul).
 
Good to hear Jetsam. Do you have it in direct contact with either the insert or liner?

Yes to both. The liner gets very hot, the back of the insert not so much.

I probably wouldn't smell it if the roxul on the liner did have an odor; that would be trapped in the chimney. There are airways from the room to the inside of the fireplace, though.

Roxul used to do sales demos. They'd take one of those little handheld butane torches and crank it up and set it on the table with the flame hitting a block of Roxul. After a few hours it does actually erode a little hole in the Roxul, but it never smokes or stinks or catches fire.

For reference, that's a roughly 2600°F flame, much hotter than anything your stove puts out.

I guess I should be saying "Rockwool", but it was "Roxul" back then. :)
 
Good to hear Jetsam. Do you have it in direct contact with either the insert or liner?

Hopefully this helps your piece of mind. I have been burning hard all day. Smell was gone before I even woke up this morning.

It lasted for about 12 hours. Everything back to normal here
 
Great to hear Bushels. I burned hot for about 4 hours today, all I could squeeze in (as a new burner I'm too hesitant to do a super hot burn while away). Still some smell...I'd like to say it has lessened but I'm not sure. It's still strong enough to be unpleasant.

Can you let me know if you get any smell the next time you get it up to temp? Thanks
 
Great to hear Bushels. I burned hot for about 4 hours today, all I could squeeze in (as a new burner I'm too hesitant to do a super hot burn while away). Still some smell...I'd like to say it has lessened but I'm not sure. It's still strong enough to be unpleasant.

Can you let me know if you get any smell the next time you get it up to temp? Thanks


I have been burning now for 48 hours straight and probably will just keep it going for the season. I don’t like starting and stopping. My house works best when i keep a steady flow. If it heats up outside, i can let it die down during the day and will have coals for an evening restart. The smell was only present on the initial fire for about 12 hours. From Friday morning until now, everything is back to normal.

The insulation and block off plate was time and money well spent. My insert is operating in a way I could have only dreamed of. I used to wake up after an overnight burn with some coals but a cold insert blowing (not cold) but coolish air. Now, the last two mornings I’ve had not just a warm, but an (appropriately) hot insert. I haven’t even turned the blower on past the lowest speed, too warm otherwise. That will change when we hit the negatives in January and February. I am also using a noticeablely less amount of firewood. My burn times have increased by quite a bit resulting in less firewood usage. And when the insert stays hot, the blower keeps pumping hot air. So coals in the insert that are keeping it warm/hot all night are allowing for much better overnight heating. Can’t believe I went 6 years without the block off plate and insulation.
 
Awesome results! I had some hot coals and the insert was still hot (about 350 maybe stove top, but about 480 in firebox area) almost 7 hours after a half load of Jack pine. I can only imagine how a full load of oak will perform. The insulation definitely helps (now, to just make a block off plate and find a way to fully seal the insulation on the sides and back).

Another bonus for a part time burner like myself is that the insert stays room temp when not burning, even on my external fireplace. The surrounding brick was at 62 degrees this morning while the insert was at 68 which is what the rest of the room was at. I know prior to insulation the bricks in the firebox would get down to like 40 degrees when it gets real cold outside.
 
Any time you paint your stove or put anything new up against it, it will smell for 3 or 4 fires at least. This is nothing to worry about. It never doesn't happen.
 
I wanted to add to this post regarding the Roxul (rockwool) smell.

I have been using my Osburn 1600 insert for years and it never had a smell. This year I added rock wool behind the insert and above it, trying to form a block off plate and keep more heat in the house.

After lighting the insert for the first time after adding rock wool, there was a distinct smell, when the stove got hot. The rock wool is about 3 inches away from the insert jacket.

Smell has to be coming from rock wool as it’s the only thing different. I did some online research. The MSDS for Roxul states that the first time the material is heated above 492 degrees F., the binders will decompose and cause a smell, and the smell can be harmful. The MSDS advises avoiding the smell. It has dissipated, but still noticeable, as the stove is cooling off a bit because it’s time to reload. I did not open windows, probably should have.

I am hoping it goes away and does not come back. I’m about to reload the stove now, I will post an update. My thought process is a one time exposure to the chemical smell is probably not a big deal especially in my large house with big rooms and tall ceilings. However if the smell happens every time I use the stove, I’ll just tear out the rock wool because I don’t want to expose the family to chemical smell and we use the insert all winter long.
 
I am attempting to post the MSDS below for anyone who’s interested: the section to review is section 10.3.
 

Attachments

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Update:

It’s 25 outside and very windy. I reloaded the insert and it’s burning great with lots of secondary flames, really throwing the heat.

Roxul smell is basically gone. I notice it faintly when I get very close to the stove. If it becomes bad again in the future I will update. I’m satisfied with the Rocky install at this point.
 
Update:

It’s 25 outside and very windy. I reloaded the insert and it’s burning great with lots of secondary flames, really throwing the heat.

Roxul smell is basically gone. I notice it faintly when I get very close to the stove. If it becomes bad again in the future I will update. I’m satisfied with the Rocky install at this point.

Your experience is very similar to mine. It basically lasted for 12 hours for me. Week two of burning now and haven’t smelled it since day 1 after adding the Roxul/block off plate.
 
Hey guys, it is February 1st ,2019..so a few months after you have opened this thread. Could anybody tell me what they have experienced in the last few months as far as roxul off-gassing? today I have done exactly the same thing you have described to my wood burning insert. I felt it was losing too much heat so I insulated both sides the back and double or triple layer on top. As soon as I lit the fire I smelt the odor you were describing! I have a cranking on high for the last couple hours hoping that it will eventually off gas, will it? Has it for you? Please let me know it has! Because it is throwing back a lot more heat back into the house. I I would like to keep this configuration without the odor and potentially some health risks. Any response would be greatly appreciated

R
 
I haven’t noticed any smell since the first time that the Roxul was heated. It was quite noticeable that first time, and lasted a few hours. Since that was in the fall I opened a few windows to air the smell out. Next day there was no problem. My insert has burned at least a full cord of wood since the install, and no troubles. Hope this is helpful.