How to "shut down" at end of night?

[Amin1992]

Hey guys. Have a wood stove insert and am new to all this but really enjoying it so far.

A lot of nights when the fire is down the coals, I am done burning (the house stays warm all night) and just want the coals to go out.

What is the proper procedure here? At first I was closing the air intake all the way but read that was bad because of creosote buildup and the glass was heavily tarred up in the morning.

Lately I let the coals go and fully open the air intake to let them burn out. The glass still gets dirty by morning though, but not as badly as with the air shut.

Is this what I'm supposed to do when not doing an overnight fire? Or am I supposed to shovel out the coals before bed? Or something else?

Thanks guys!

 

[alivegas99]

Why don’t you just let it burn out normally through the night?

 

[Amin1992]

I guess that's what I'm asking haha. Can I just let it burn and go out overnight? Didn't want to create a creosote problem

 

[peakbagger]

Coals after a good fire do not form creosote. Creosote is formed from the stuff including water vapor that is "boiled off" from the wood during the initial phases of the fire, if the fire is not hot enough then this mix of water vapor and gases convert back to solids that collect on cooler surfaces in the stack. By the time you are ready to go to bed after a few hours of burning, the wood has been boiled and baked so the only thing left is mostly coals containing carbon. If the fire is hot enough the coals burn completely to CO2, if its not hot enough they burn partially to CO (carbon monoxide). Both of these combustion byproducts can not form creosote as they are non condensable gases. They hopefully go up the stack.

The worst thing to do is throw some logs on and crank the air down to keep a bed of coals until the morning as the logs will "boil" away at low temperature and head up the stack to point where the gases condense on the cooler chimney walls and turn into creosote.

 

[Ctwoodtick]

Once you’re down to coal, . There is no creosote prodoced so turned low is fine.
With it getting colder soon, you can pack the insert up with wood. Let it ignite (not to the point of being one big fireball though) and then throttle back gradually. You may be able to throttle back to near fully closed (which is in reality not closed- there’s always some air getting into air inlet to insert). I’ve learned to time it right so that I’m not putting this load of wood on very hot coals. What I mean is I wait for no more flame in insert and coals burned well down. Loading line this with a higher stove temp can lead to over firing the insert. I have a magnetic thermometer in the slot on top of insert (the stovetop). I try not to fully reload wood When stovetop temp is over 300.
Do you know how old the insert is?

 

[Sawset]

Here, once the process of startup is complete, and the stove is up to operating temp, and is set to enough air to operate cleanly - I usually don't touch it until either adding fuel, or it's out. The batch process seems fairly stable from begining to end without needing adjustments in between. If I wake up to a cloudy glass, it's usually because I tried to keep too cool of fire to begin with, such as starving it for air, or too small of fuel load.

 

[BigJ273]

My “bedtime” routine usually takes about 40-45 min after reload, and gradually shut down before I get it just where I like it for the overnight. It’s a learned process. But no, u do not need to shovel out red hot coals. That would be a disaster. The stove is meant to burn.

 

[Bad LP]

I just let it die on the settings it was running on.

 

[Amin1992]

Thanks all for the input! Is it normal then for the glass to turn brown/black overnight? That was my concern - wasn't sure if that was a sign of something wrong. Good to know it's not creosote!

The insert is 3 years old. Previous owner was a dunce and half assed every project in the house including this one. Just slammed the insert into the fireplace opening... I had a proper liner put in after saving up for a year. In the mean time I cleaned out the stove and did a ton of research. You all have been such a great help here!

 

[Ctwoodtick]

I would not expect black glass after an overnight turn. Perhaps son very light brown or white-ish flash. The black glass probably points to either would it’s not quite dry yet or turning down the wood way too early.

 

[xman23]

It's surely stove, installation, and wood condition dependent. Unseasoned wood, which you probably have, smolders and blackens the glass as the burn slows down. Shutdown, by opening the air is what you should do. Less or no blacking of the glass will happen as the wood your burning ages. But this will take using wood that's seasoned for years. Particularly if your burning oak.

Here's what I do, which may help. Before the shutdown, burn the stove hot and burn all the wood to a bed of red hot coals. The coals will burn cleaner than unburned smoldering wood. Open the air fully.

 

[brenndatomu]

Black glass could be just some soot (thin dry almost dusty layer, and wipes off easily with a damp paper towel...which I guess technically is stage 1 creosote) or it could be legit creosote, stage 2 or 3...hard to say without seeing it.

Learn how to identfy the different stages of creosote

Creosote is an inescapable factor of a wood burning appliances. Learn here how to identify and remove it.

blog.northlineexpress.com

As was stated. black glass means wet wood, or air setting too low, or possibly loss of draft during the night (which could have quite a few different causes)

 

[Ctwoodtick]

It's surely stove, installation, and wood condition dependent. Unseasoned wood, which you probably have, smolders and blackens the glass as the burn slows down. Shutdown, by opening the air is what you should do. Less or no blacking of the glass will happen as the wood your burning ages. But this will take using wood that's seasoned for years. Particularly if your burning oak.

Here's what I do, which may help. Before the shutdown, burn the stove hot and burn all the wood to a bed of red hot coals. The coals will burn cleaner than unburned smoldering wood. Open the air fully.

As long as the OP isn’t keeping air open for too long and overfiring.

 

[Sawset]

The first year here I ended up with unseasoned wood, some rain soaked, some just recently delivered from a local supplier. It made the stove difficult to control, and did darken the glass some. There's a difference between ash collecting on the glass, and soot or creosote bonding to the glass. I had the latter, which just water would not take off. I got through it without too much trouble, but it was just more of a hassle keeping the temps in a clean operating range. By the time it was time to walk away though, nighttime, the water had boiled off and was usually set to leave it alone. Sometimes it would be 1-1/2 hours before I could confidently leave it alone. Now, 15min usually and it's stable and set to run. With dry wood, the glass stays clean, with only gray ash collecting over the course of weeks now, instead of some blackness in a matter of hours or a few days.

 

[Amin1992]

Thank you all for the advice. The black/brown on my glass wipes right off with a towel, so I suppose it is just an ashy dust and not major creosote build up. I will follow your advice, though I don't think I have a draft or wood problem. The Oak is 5 years seasoned (old owners left it here for me) and the liner is brand new and drafts awesomely. Will keep an eye on it. thanks again.