Am I wasting my time? - Add on furnace

[mattinpa]

I keep wondering about this wood add on furnace before I put the time into installing it. I had planned to put it in my basement beside my oil furnace. I have a 2 story 2100 sqft home that has little insulation. Is this furnace going to help lower my heating bill considerably, or am I chasing a dream? The more posts I read, the more I get the feeling that my 2nd story is not going to be heated very well. Oil does fine, but the idea is to cut back on oil. I just don't want to install it and be very disappointed.

The add on is the Englander they sell at lowes and home depot

(broken link removed)

 

[begreen]

The add-on furnace should do an ok job as long as it's installed correctly. Some of the bad system reports have skipped adding backflow dampers. With a good setup, the furnace should add a lot of btus into the house. Running it will be more work than setting the thermostat on the oil furnace and it will be harder to maintain an even house temperature during shoulder season burning unless you burn shorter, hot fires and then let the furnace go out. During the brunt of winter, when you can run full loads of wood at a good burn, it could make a sizable dent in the oil bill.

Whether it will do a better job than getting the house properly insulated is another question. That would be my first priority. Insulation and caulking will pay back year round, no matter what the fuel.

 

[mattinpa]

Had to go the fast and cheaper route for now. Any other tips and tricks for installation would be appreciated. I'm sure I'll be asking alot of questions in the coming weeks.

 

[WoodNotOil]

This thread may be helpful https://www.hearth.com/talk/threads/9970/

 

[begreen]

Sorry to hear that Matt. Do you have 3-5 cords of nice, dry seasoned wood already? If not, I'd put the 2 grand into blown-in insulation and spend a weekend with a caulking gun and some Great Stuff.

If you do have the wood and are ready to go for it, then post some pictures of the existing oil furnace that show the supply and return plenums coming off the furnace. That will help alot.

Also, how will the wood furnace be vented? What will be used for the flue?

 

[mattinpa]

I don't have alot of seasoned stuff. I have about 8 cord that's been seasoning for about 5 months now. I do have access to TONS of hard dead wood. Friend had his 130 acre property logged 6-7 years ago and there's dead stuff everywhere. Not rotten, just dead and hard as stone. Will this burn well? Anyway, back to the furnace. Since it's an add on unit, does my blower on my oil unit need to be on constantly, or can I rig up a tripping system or manual switch? I do have an older unit, probably 30 -35 years old.

Thanks

 

[oilbegone]

For about 25 years I heated my house with an add on wood furnace. I had it tied into the duct system with a switch in the duct work that turned on the oil furnace blower when the duct heated up. My oil man laughed at me but it worked really well for a long long time. Good luck!

 

[oilbegone]

Sorry I forgot to mention that I enclosed the wood stove except for the doors in duct work sheet metal with about a 2' x 2' x 2' empty sheet metal box on top that had the switch in it . I hooked the top of the box into the ductwork of the oil furnace with about a 10 x 14" duct.

 

[mattinpa]

Wow! What kind of swtich would you use for something like that?

 

[oilbegone]

I will look online to see if I can find something similar. Probablly thermostatic was the wrong terminology. The switch was mounted in the ductwork, it was about 4" long with a bent piece of metal that when heated up made the contact to turn the fan on. One of the professionals on the forum will probably chime in.

 

[laynes69]

Probably a limit/control like the older furnaces used. We use a limit control on our wood furnace. I have mine in series, but to install them in parallel will be okay also. Like said they will dent the oil bill, for us we have just about eliminated our propane usage heating a 2400 sqft victorian with a wood furnace. Difference is, a pretty tight home with adequate insulation and good windows and storms. Makes a world of difference. I wouldn't run the blower on the main furnace alot with the woodfurnace, only because it will temper the air. When the woodfurnace gets really hot however, then have the main furnace kick in its blowers to assist in heating. The only thing that I see wrong on those wood furnaces, is the single outlet for heat to travel through a large duct system seems inadequate for the sq footage they claim to heat. Never the less, they will put alot of heat out and should perform okay to help heat your home. Like said before, 2 very important things, proper dampers, and clearances to combustibles. They are very simple to install.

 

[oilbegone]

I also had the bottom of the stove enclosure tied into the cold air return of the oil furnace. Not as efficient as todays equipment and the duct work was probably not sized properly. However, I was able to heat entirely with wood unless we were away for more than a day then the oil would kick on.

 

[mattinpa]

"I wouldn’t run the blower on the main furnace alot with the woodfurnace"



I thought you had to in order to help blow the air? Am I wrong?

 

[oilbegone]

I ran mine alot for over 25 years, over that time I replaced one motor and a couple start capacitors. With the wood furnace going it would run as long as there was sufficient heat in the duct work to keep it on. The wood stove had a motorized damper that was controlled by a second thermostat so you could turn down the temperature and make the fire last all night. Let me know if I am boring you all with old technology.

 

[laynes69]

Hell, mine is old technology. I ducted mine in series so I only use the LP Furnace blower, nothing else. I had mine where it was parallel and it wouldn't work near as good as the series. You have a 800 cfm blower running the woodfurnace, take a 1400 cfm blower and mix in 70 degree air with 140 degree air. It will cool quite a bit. But its not up to me. Either way will work.