Fire won't burn hot enough

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ATC110

New Member
Jan 24, 2021
4
Nova Scotia, Canada
Hi guys new to the forum. So iv been having an issue for past 2 winters with my wood stove Newmac Classic I, stove is about 20 years old and iv used it for past 8 years since moving in. Stove worked great up until last year adding I'm not no wood stove expert but was raisied on wood heat. Last year I noticed an issue when I had a flue fire, not major but enough to know I had one. Had my chimney replaced by a professional not even a week later had a flue fire. Needless to say after cleaning it twice and happening twice I sucked it up and blasted the heat pump. This year cleaned the pipe had a break in fire you know burn dust off stove and whatnot. Very next fire I had a flue fire. So that's when I started my research of how hot it supposed to burn and how to properly start a good fire in the stove ( mind you iv never had an issue ). So I went and got a magnetic thermometer to stick to my pipe and do some troubleshooting. I start my fire get it up to 450°f and then cut back my draft, all seems good for 10 mins but then the fire basically goes out ( it smolders but no flame ) and drops the pipe temp right above stove to 100-150°f. The issue is my stove has a bi-metal sort of auto damper so it's supposed to open itself during the burn if need be. My issue is after the fire has actually took and the stove has heat the damper won't open itself nor can I open it because the knob is fully cranked, which leads it to only smolder at 100-150 like stated . Then when the stove actually drops down below 100 the damper finally decides it needs to open.
I've lost all trust in the stove and bought a new one because I was at a loss and it was 20 years old. My new stove works amazing burns between 300-400 ( manual damper ) but will hold its temp with damper closed. So sorry for the story book just giving some background but I want to use my old stove in my garage but also don't want to deal with the issue of the fire not really burning has anyone eliminated the auto dampers with a inline pipe damper ( sorry I don't know the terms lol ) if so do I just jam the draft door open and use the inline. Or could there be an issue with the stove itself that I'm not find myself .

Thanks in advance if you read this far. Sorry again for the story book, your community just seems too helpful to pass up on info I can get.
 
Couldn't you contact the mfg of the stove for repair help for the thermostat? Rather than jamming or cutting something off that has worked well, wouldn't it make sense to try to repair it first?

I do think the choice to not use it (take it out of your house) is the right one. At least for as long as it doesn't work as designed.
 
The Newmac has a flapper valve that would be worth inspecting and watching the action. It might be binding in which case cleaning out that area carefully may help. There may be corrosion buildup causing the flapper to stick.
 
I would say it is a good chance the bi metal thermostat needs to be replaced or at least calibrated. I am not that familiar with Newmac but most circulators have a small chain off of the thermostat spring that drops down to a baffle on the side of the fire box. If you open the door on the end and look on the front side you should see it check to see if it opens and closes the baffle as you turn the dial.
 
I tried contacting the manufacturer and have yet to get a reply on a replacement part. Searched endlessly online with no luck for parts. Yes it does have a flapper valve, but as I said its open as it should be when you light the fire but shuts way too early. The chain is attached, it's clear of obstruction on inside and out, it's opens and closes freely with zero binding. When the stove is cold pretty much any turn of the knob will change the flapper. I pretty much know it has to be the bi-metal strip failing under heat or out of adjustment. Don't make me feel crazy for trying to use an inline damper lol. Im not planning on running fires in my garage day in and out its for a day or two a week. Obviously the part would be the proper way to go, in saying that I'd rather not give money to the manufacturer that hasn't returned my call or emails which forced me to buy a stove. I'm from the place people have wood stoves made from air compressor tanks, oil drums and even people with busted glass... Im not that crazy I just simply wanna move my damper to the pipe and not pay to fix my old stove. Clearly as stated above my friends would say just run er jammed wide, open the bay door if she's too hot lol.
 
Wow, thats terrible and a pain, but I suspect your wood supply might also be an issue, since creosote deposits are the fuel for a chimney fire, whats the wood moisture of your splits, please dont just say its seasoned, when was the wood cut, split and stacked?
 
Wow, thats terrible and a pain, but I suspect your wood supply might also be an issue, since creosote deposits are the fuel for a chimney fire, whats the wood moisture of your splits, please dont just say its seasoned, when was the wood cut, split and stacked?
Iv got my wood from same guy ever since I moved in to the house. Never had a problem. I haven't directly asked how long he seasons the wood for. But I stack my wood in the spring under an over hang and keep a cord of wood inside from that time too. The wood definitely isn't wet or green. I know what burning wet unseasoned wood is like I do it at my camp and it's terrible.
 
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I know what burning wet unseasoned wood is like I do it at my camp and it's terrible.
I figured I'd ask the question because sometimes when a problem presents itself, its hard to see past the obvious, but good to hear that its all good.
 
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