Newmac add on wood furnace

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Miggss

Member
Dec 4, 2017
12
Connecticut
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Hi all. I had a few questions and was hoping for some information. I'm fairly new to wood burning other than fireplaces. I recently purchased a home with a newmac add on wood furnace. The primary heat source is oil forced hot air. I really don't know much about the system at all. I've been doing as much research online as I can but haven't found many systems hooked up the way mine is. I hired a company to clean and inspect my chimney liner hoping to gain some information there but the person who came out didn't know anything about add on furnaces. I do know the old owner used the add on furnace on a regular basis.

The furnace is in the basement and the newmac has a stove pipe out the back which ties into the liner where the chimney probably runs close to 30 feet, maybe more(half the height of the basement wall, 2 full stories, an attic and a few feet above the roof line) the oil furnace pushes air out the top enters down at the bottom of the stove. Then ducts come out the top of the stove and feed the entire house. All air leaving the air handler(even A/C in the summertime) looks to pass through the stove. On the stove itself, there is a draft control knob above the door and another small sliding damper in the door. Many of the add on furnace setups I've seen have fans on the front of the stove with thermostats.

I have had one fire in the stove and it seemed to work very well as far as heating the house nice and evenly. I ran the the thermostat with heat off and fan on and it spread the heat throughout the house well. It actually got too warm and I ended up turning the fan off. Is this the typical setup or should they have more thermostatic control switching back to the primary heat source if need be. Some of the things I've read about to be on the lookout for were not running the stove hot enough and worrying about creosote buildup. Will my set up with the very tall chimney be prone to creosote buildup more so that with a shorter chimney? With no draft fan will I be more prone to my fires not being hot enough. I've also read about the newmac furnaces being prone to cracks in the heat exchangers. What is the best way for me to monitor this? Lastly what is the best way to monitor overfire being that this is now tied into my duct work. I have plenty or access to firewood and would like to use the furnace but want to make sure I am doing so in the safest manner possible being that I am new to the wood burning business. I will attach a few photos of my setup. I appreciate any bit of info I can get on add on wood burners and am excited to use mine.

Thanks.
 
Can't tell you much about a NewMac specifically, but if the house got too hot, you probably loaded too much wood. It takes a bit of experience with a new house and furnace to lean how much wood to load to match the upcoming weather in the next 8-10 hours
 
Should be some basics in the manual? Also every install can have its own twerks - previous owner would be the best source for specific hints.
 
My dad had one for close to thirty years, very reliable. Burns lots of wood, you’ll figure out how to run it after a few burns. I don’t think we ever “overfired” it.
If your power ever goes out, you can burn a fire in it and take the side panel off to radiate the heat.

The reason it’s oil before wood, is the wood burns hotter so you don’t want that running through the oil furnace.
Treat it the same as a wood stove, burn seasoned wood and burn it hot, we ran ours 24-7 during the cold weather.

You’ve had the chimney cleaned first, that was a good start. Exterior chimney are always more prone to creseote more than an interior chimney due to being colder all the time, height doesn’t necessarily mean anything.
 
Thanks for the replies. So I've spoken with the previous homeowner and he gave me a rundown of how to control the thermostats and open and close the different zones to control the heat in the house. He did say the chimney didn't build a ton of creosote but the 6 foot section of stove pipe coming out of the stove and into the chimney did build a lot of creosote up. I assume this is because of the 2 90 degree bends and the third where it turns and the chimney and goes up the side of the house. I've only had two fires but have tried to burn them nice and hot with both dampers run fully open. Even doing so the temp on the stove pipe just after the first turn only gets to 175 to 225 degrees. I know he ran the stove often with the dampers closed down to get longer burn times. Is the temperature in the 200 degree range hot enough or should I be trying to burn a hotter fire?
 
Are those temps on the outside of the pipe? If so the internal temp is roughly double that and is OK...but 200 internal is too low.
 
Yeah that's on the outside of the pipe with a magnet thermometer. Is that a fairly accurate way to keep an eye on my fire or is there a better way? Sorry for the basic questions but just trying to learn as much as I can.
 
Better than nothing...a probe type thermometer that goes into the stove pipe will react quicker and be a little more accurate.