Wood furnace help

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Matt99

New Member
Nov 7, 2016
8
Canada
I've recently purchased a home which has an old wood furnace. I've never dealt with a wood furnace before but it seems pretty staiight forward and works well. The only issue I have is with the door on the furnace. There is no seal around the door just metal on metal when shut. There seems to be a large build up of tar looking creosote around the door, when the fire starts to cool down over the night and I go to open it in the morning the door sticks shut badly from this build up. Can anyone suggest a fix to this? From me yanking on the door as hard as I am I am scared the door will bust free from its latches. Which it is already getting a little sloppy in. Any suggested help or guidance here would be greatly appreciated.
 
You might need a gasket. But we have no idea what make/model of furnace. Pics might help.

It could also be wet wood & poor burning practices (my first thought), inadequate draft, deficient chimney setup....
 
I will take pictures and add make and model when I get home.
For now I can say that the wood I am currently using has been in a dry basement for about a year so it shouldn't be wet. As for burning practice I start the fire with the thermostat set at 22degree C. If the temperature in the house is below this the draft will automatically open if it is below this. If the house house is at or above 22 I leave the draft open slightly until the fire gets going good (for about 15 min. Then add pieces of hardwood as needed.
 
Overloading for heat demand (somewhat common for this time of the year) can make a creosote mess. Have you check your chimney lately?

Also, if the wood was put in the basement unseasoned, it likely won't dry a whole lot. (Assuming also it is split?).
 
[Hearth.com] Wood furnace help
[Hearth.com] Wood furnace help
[Hearth.com] Wood furnace help
 
Added some pictures of what I'm seeing.
The furnace is from the lunenburg foundry and engineering. Model # 24S-compact. I fought you'll find anything as that is from a small town in Nova Scotia Canada. Made in '86
I havent checked chimney since starting the fire 2 weeks ago but I have looked in the pipe from chimney to furnace and there is the start of a buildup of creosote.
 
That looks like it may be a boiler. Does this unit have air ducts? Looks normal if it is a 1986 boiler.
 
Ok. Furnace with a hot water coil it is. I bet if you put a small spacer so the air intake can't close all the way, it would help.
 
Ok. Furnace with a hot water coil it is. I bet if you put a small spacer so the air intake can't close all the way, it would help.

Someone else mentioned that I should do that but I thought it may give too much air flow. I have been using a clothes pin to hold the air vent open slightly just to get it started. I will give it a try to stay in longer. Thanks
 
Welcome to hearth, Matt99!

I have been using a clothes pin to hold the air vent open slightly just to get it started. I will give it a try to stay in longer.

It looks like your air vent could get really hot after the fire gets going. Are you talking about a wooden clothes pin or a metal binder clip?
 
It's a wooden clothes pin. The heat coming from the vent doesn't seem to affect the pin

Sometimes it's after the house catches fire that it's easier to see how the unexpected can happen. You know your furnace better than I do to decide whether to risk it and things probably won't go wrong, or just find something metal and remove the risk.
 
Better safe than sorry. Although I wouldn't mind if my place went up.
 
Sometimes it's after the house catches fire that it's easier to see how the unexpected can happen. You know your furnace better than I do to decide whether to risk it and things probably won't go wrong, or just find something metal and remove the risk.

You know, sometimes it only takes a few worlds to realize the error of your ways. Yours my friend have made me realize how stupid it is. And I thank you for that haha... wooden clothes pin... wtf was I thinking..
 
Yours my friend have made me realize how stupid it is.

No shame at all. Heck you should see some of the stupid things I've done that still make me cringe years later. I count on others to keep me out of trouble, I just hope to return the favor.

Besides, I noticed after my previous posts that your same door has a wooden handle. ;lol So I can understand that wood might not be obvious as a risk, and maybe a clothes pin is ok. But there's no need to chance it.

Welcome again. I look forward to your posts.
 
That hard glassy creosote around your door is more than likely forming up in the chimney too. Mine always did. The auto dampers are a nice convenience, but are just the best at making creosote form.
 
There likely was never a gasket on it, or it likely was never designed with one.

So, nature of the beast - but you should be able to limit its extent by making sure your wood is as dry as it can be, and not loading more wood in that should be loaded in for the particular heat demand at the time. Any time the damper closes with a fire going inside, it will start creosote forming. The more wood/fuel inside when that happens(amount of load), and the longer it stays closed (amount of heat demand)- the more creosote.

Might also be a possibility you might be able to reduce it some by unhooking that DHW coil & not using it anymore, but I suspect that is only playing a small part.
 
Sometimes it's after the house catches fire that it's easier to see how the unexpected can happen. You know your furnace better than I do to decide whether to risk it and things probably won't go wrong, or just find something metal and remove the risk.
I do not consider a clothespin of one composition to be any more "risk" than another composition. If there would be any negative, the wooden clothespin might burn away and allow the damper to close. The entire unit is sitting on a concrete slab. What is the risk of a burning clothespin on a concrete floor? Smoke detector activation, unwanted burned clothespin smell, and maybe a stain to the floor.

Now if this was installed in a hay barn, maybe some concerns there. There sits the wood burning furnace with internal temps reaching over 1,000F at times and the plenum directly above.

Common sense should definitely include consideration for safety. But, to decide based on all of the one in a billion chances would keep every one of us from striking a match, ever. On the other hand, if the OP keeps flammables right there on the floor, under the firebox door, I will concede there is a safety issue with the wooden clothespin. Just my opinion based on decades of wood heating experience (without a single burned structure).

Concerning the creosote buildup on the door jam, it looks identical to the door jam on the Eko25 I heat with. Thanks to this site, I did not freak out over it as it has been stated to be standard conditions.

Best of luck Matt, in the coming heating season.
 
What is the risk of a burning clothespin on a concrete floor? Smoke detector activation, unwanted burned clothespin smell, and maybe a stain to the floor.

I guess it's a difference of philosophy. You're comfortable with the scenarios you can imagine. I'm paranoid about the scenarios I can't imagine.

I remember a guy on here describe he put the day's firewood in a tote safely away from the furnace. Basement flooded several inches after he left. Enough to float the tote into the hot furnace, but not enough flooding to reach the fire. I don't remember if the tote caught fire, but scared the crap out of him and what could have happened. Who could have imagined that?

I admit I have a tote for firewood, too (with holes in the bottom). Point is, I try to avoid fire risks that are easy to avoid.

At least I think that was on hearth some years ago. Anyone else remember that one?
 
It is normal to have creosote build up on the walls of your fireplace. Restricted air supply, cool surface flue temperatures can cause creosote build up. You should clean it by using an anti- creosote liquid and powder. But if still the problem persist, you should better have a talk with some good heating system maintenance NJ technician.
 
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