Forced air furnaces

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Matty03

New Member
Apr 20, 2021
5
Wisconsin
Good evening guys,
So here is my situation. I have a 3000sq ft house single story that is with a finished basement. Two years ago we put in a jotul kennenback 450 in our living room which is almost dead center in the house. This thing heats really well but the heat doesnt seem to reach our back bedrooms. We absolutely love our stove and now I’m looking at adding a forced air wood furnace to really pump some heat in the house and to the back bedrooms through our duct work. We have a natural gas furnace but as most of you could probably agree there is a huge difference between wood heating sources and natural gas ones. I would like to buy a used one and have been having a hard time finding one rated for our sq footage. So do these wood furnaces work really well? What kind of burn times should I expect to get. Should I get one rated for 2000 sq feet and just feed more wood into it? The new epa standards seem to really cut down on what models are available. What do you recommend? I’m not sure how well these furnaces work and if I’m over thinking the whole sq rating on them. Also I have a double chimney in my house. The fireplace on first floor is exhausted through one with a stainless liner if I get the wood furnace could I line the other chimney and run it through there?
 

brenndatomu

Minister of Fire
Aug 21, 2013
6,567
NE Ohio
You'll get more help if this was in the "boiler room" part of the forum.
What's your heat load ($bill) like?
Sq footage doesn't mean as much as how the house is constructed, and insulation/air sealing levels...a 2k furnace might be fine, or a 3k furnace might not keep up...just depends.
What do you recommend?
You only have 2 choices in new ones right now...Drolet Heat Commander, or Kuuma Vaporfire 100...and stay away from anything made by Fire Chief or Shelter since 2017!
If going used, you can add to the list a Drolet Tundra II would be OK (if big enough) or a Drolet Heatpro if you need bigger. (or a PSG Caddy/Max Caddy...basically all the same furnaces, just the Drolet is/was sold in box stores, the PSG is "dealer only pro line"...slight differences between the 2 lines)
Also I have a double chimney in my house. The fireplace on first floor is exhausted through one with a stainless liner if I get the wood furnace could I line the other chimney and run it through there?
Sounds reasonable, as long as the chimney is big enough to take the liner with insulation.
 

Matty03

New Member
Apr 20, 2021
5
Wisconsin
My house is pretty well constructed. We were on our 3rd week in a row below zero with the wind chills in the negative teens and I believe our highest bill was 185 that is heat and electric. Typically our bill is around 150 heat and electric. I tend to run the jotul stove as much as I can but we both work and it only runs from when I get off work till I go to bed generally. I can get a really nice energy king ek480 used or a woodchuck 2900 both in excellent condition for right around 1k. So if my house seems to be insulated well enough should I go with either of these used models and call it a day I believe they are rated for 2500sq feet in general.
 

blades

Minister of Fire
Nov 23, 2008
3,679
WI, Leroy
Matty- call Kuuma and talk to them direct. As they are located next door MN. You could even make a couple day trip out of visiting them. The most difficult part will be your flue install. For me that requires boring through a poured concrete basement wall and then going up outside unless I want to place unit almost in the middle of the basement. Then go straight up through the main floor and then through the ceiling finally exiting at the roof. ( 1990 build no brick and motor flue- all plastic out the side wall.) the other option would be to do a small furnace room add on to the existing structure at the first floor level ( would have to assessable from inside the home to be considered part of the home envelope) ( i do not have a walk out basement) (this gets around any OWB restrictions on a purely technical level). In my area the county and the local codes banned any type outdoor wood boiler. Those already around are grandfathered which is just about every farm in a 50 mile radius ( of course they do not list coal as a fuel source nor specifically state anything about a forced air furnace being outside - but I could easily invision a court fight on the semantics). Played the feel good greenie code game a few times already) I am fortunate that my stove -centrally located- main floor- heats my 2200 ft ranch almost evenly throughout the floor plan. Previous ranch had the cold bedroom syndrome- messed with a cheap wood furnace in basement in that place worked but to many equipment issues.
 
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brenndatomu

Minister of Fire
Aug 21, 2013
6,567
NE Ohio
I can get a really nice energy king ek480 used or a woodchuck 2900 both in excellent condition for right around 1k
Well, you could...but those are old school style...and as with most things, you kinda get what you pay for with wood furnaces...
 

Matty03

New Member
Apr 20, 2021
5
Wisconsin
I have a double chimney in my house. Our jotul insert exhausts out one chimney and our water heater exhausts out the other. We will be upgrading our water heater in the next few months to on demand and venting out exterior wall in basement per code. The hole is there just needs to be a little bigger which is not a big deal for me. My question is can I use both chimneys with a stainless liner inside them and burn both stoves at same time or is that illegal ? I’m sure I would have to raise the flue higher than the other on top of the chimney cap
 

sloeffle

Minister of Fire
Mar 1, 2012
870
Central Ohio
I can get a really nice energy king ek480 used or a woodchuck 2900 both in excellent condition for right around 1k.
There is reason they are for sale.

I looked at an Energy King furnace when I bought my Caddy, good luck on cleaning the HX tubes. I'd stick with a SBI or Kuuma built furnace.
 

blades

Minister of Fire
Nov 23, 2008
3,679
WI, Leroy
As long as they are 2 separate flues contained in the one structure ( not co-joined somewhere in the run) , yes. The catch being if you can get an insulated liner down it as mentioned earlier. basic code is any solid fuel appliance must have its own dedicated flue. It was common in many places to have the conventional furnace (gas or oil ) sharing one flue with hot water heater( oil or gas). And they could be mixed.
 

JRHAWK9

Minister of Fire
Jan 8, 2014
1,728
Wisconsin Dells, WI
Thank you I appreciate that. Have any of you had good luck with a forced air wood furnace?

I think all of us have, at least those with furnaces worth a damn anyway. LOL

-HERE'S- my review of my Kuuma VF100.

Where about are you in WI?
 

Matty03

New Member
Apr 20, 2021
5
Wisconsin
Wow jrhawk that was a very good read thank you for that. You seem to be very intuitive with it all. I’m not sure what you do for a living but you should write reviews
 

Brokenstone

Member
Jan 13, 2017
19
indiana
Thank you I appreciate that. Have any of you had good luck with a forced air wood furnace?

I have. I run a later model Yukon Husky/Eagle. It is not the furnace that a kuma is but is proven tested technology that has been used for many decades. It heats my 2700 sq. Ft. well. No longer available due to EPA regs.
I use about 3 cords a year. A kuma should do just as well or better.

The advise posted above about good furnaces is correct. Avoid others.
 
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trx250r87

Burning Hunk
Nov 30, 2012
188
NE Wisconsin
I have owned a DAKA model 621, Drolet Tundra and now Drolet Heat Commander for a combined total of 15 years burning wood. All three did a great job heating but the Heat Commander has been the best by far!

A few years ago I had an opportunity to purchase a lightly used Kuuma VF for a really good price, but I couldn't justify purchasing due to the fact that it didn't have a glass door. I'm not knocking the Kuuma as I know they are exceptional units with a proven track record, however, I am 100% satisfied with the Drolet Heat Commander I purchased last fall.


Eric
 
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