Wood Furnace Overheating

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You can use these type furnaces as a stand alone.
Necking down the duct work restricts your air flow and keeps the firebox hotter. Change your duct so it's 8" all the way to the register and it should keep the furnace cooler.
It sounds like there may be other problems but I wood start with the duct work.
 
It can be used as a stand alone, but the output is going to be hot. Best to follow directions and feed into the hot air plenum with the 2- 8" round supply ducts from the wood furnace, not directly into registers unless you can maintain 6" from combustibles at all points including at the registers and can ensure that the register is sized to match the 8" pipe.
 
I basically went with the 4" ductwork because of a fairly low ceiling in the basement. I also had to go with stand alone option because my other heat is electric and doesn't
have the plenum setup of conventional furnaces. If I go with the 8" ductwork to the registers, will I have a problem if the registers are in contact with the flooring and carpet? I was told somewhere that heat might not catch wood on fire right away, but over time it degrades the wood to the point of possibly catching on fire. Is this correct?
 
You need to provide clearance to combustibles because it's possible for unusually high temperatures. You can transition the 8" round to 4'X10" rectangular.
 
garrymg7 said:
I basically went with the 4" ductwork because of a fairly low ceiling in the basement. I also had to go with stand alone option because my other heat is electric and doesn't
have the plenum setup of conventional furnaces. If I go with the 8" ductwork to the registers, will I have a problem if the registers are in contact with the flooring and carpet? I was told somewhere that heat might not catch wood on fire right away, but over time it degrades the wood to the point of possibly catching on fire. Is this correct?

What is the electric heat, ducted via a furnace or baseboards? I was assuming this was a ducted system, though perhaps that is wrong. If this is not tying into a current duct system, it may be beneficial to put in a trunk duct that is fed by the wood furnace and then take off 6" round runs to distribute the heat. This will take some work and skill with working with sheetmetal. If you're up to it and can post a basic floor plan including the basement stair location, I will sketch out a trunk run.
 
I finally got 8" ductwork going to the registers. It definitely dissipates a lot of the heat into the basement area, but still has more than adequate heat coming up out of the registers. I can now run the furnace at higher temps to make sure I'm not creating a creosote problem. I couldn't do this before because ductwork was getting very hot.
I have a thermometer on the face of the furnace, will this give me an accurate burning temp? Thanks for all the help.
 
exactLEE said:
Reducing it to 4" is most of the problem.
BG beat me 2 the punch!

yep good info to have
 
garrymg7 said:
I finally got 8" ductwork going to the registers. It definitely dissipates a lot of the heat into the basement area, but still has more than adequate heat coming up out of the registers. I can now run the furnace at higher temps to make sure I'm not creating a creosote problem. I couldn't do this before because ductwork was getting very hot.
I have a thermometer on the face of the furnace, will this give me an accurate burning temp? Thanks for all the help.


it should help you develop a good base line on where your temps are best. Its just one more tool to help run it better.
 
I used to keep my furnace in the 400 degree range in the front above the loading door. If you want to know how its burning, watch your chimney. I could push my temps higher, but I had a lot more air going through the furnace.
 
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