Add on furnace low useage?

[tjcole50]

Looking to get some more heat of course! But my wood stove provides 90% of my heating but during these gnarly cold snaps , would an add on furnace be worth. Like everyone else I'm trying to get off the propane. Now I currently have a wood stove on my main floor 1700 sq ft house. I also have a existing chimney in my basement so adding a 2nd nc30 is an option. But will still cost me the amount for a stove + 30 ft liner. Now I'm wondering if adding on a wood furnace like the englander or drolet heatmax would be a benefit. I would only use the add on wood furnace for the week stretches like we are having where the stove can't handle the work load. Current location of my propane furnace would be great for an add on which there is a large basement window I can make a chute for wood supply. Just curious if you guys think the 2500-3000$ is worth it just to have the add on furnace run 10% of winter vs filling the propane tank
Rambling done

 

[blades]

Most of the wood add on or other wise furnaces in that price range subtracting the liner are woodhogs and creosote making units as compared to your NC30. Most are at best 4 hour usable heat. Generally are very hard to control- seems to be an all or nothing run. Plenty of folks here use them some good some not so hot. The other issue is getting that usable heat up stairs. There is a different set of codes concerning duct work for solid fueled appliances - duct work clearance specs. additionally you will need back draft dampers between the two units as well as ducting return air to the intake of the add on. Otherwise you won't get much from it. So from a perspective of quick and less cost another 30( or similar) in the basement, leaving the stairs door open & and fan to push cold air down the stairs might be better choice. I have one 1300 model hotblast, appropriately named - short blast of heat I did tie into the ducks, but had to undue because of codes. No way was I going to re-arrange 50% of the duck work to accommodate code and Insurance concerns. I never trusted it even when home to keep an eye on it. Ok so that all said it did reduce complete reliance on the utility for heat. I have a 30 upstairs it supplies 98% of my heat, in this super cold wind whipping stuff I do have to help it along with either the hotblast or the NG unit, most use the NG as hauling splits down the stairs is a pain. One other thing basement installs are notorious for draft problems, particularly on start up with a cold flue, appliance not withstanding.

 

[tjcole50]

You have nat gas with all this wood burning appliances?

 

[KindredSpiritzz]

+1 on "are woodhogs and creosote making units"
Im looking at getting an Englander stove next year just so i can get away from that on my (vogelzang) wood furnace. Hoping the stove can take care of 90% of my heating and only use the furnace 10% of the time. If i was in your shoes i'd just use the propane furnace to fill in when needed. It'd be cheaper than dealing with the cost & hassle of a cheap wood furnace. Course for $2000 you can get a pretty good wood furnace with secondary burn but i still don't see it as being wroth it for that kind of minimal heat load.

 

[STIHLY DAN]

Your looking at it all wrong. Get a good wood furnace like the Kuuma, do the ductwork correct, and use it as main source of heat. Use the stove for shoulder season, and on low for an ambiance fire if that's what you like. You can have the whole house at an even temp and not get blasted out of any room. Not to mention not having to adjust anything at any point of the fire.

 

[tjcole50]

Your looking at it all wrong. Get a good wood furnace like the Kuuma, do the ductwork correct, and use it as main source of heat. Use the stove for shoulder season, and on low for an ambiance fire if that's what you like. You can have the whole house at an even temp and not get blasted out of any room. Not to mention not having to adjust anything at any point of the fire.

Can the Kuuma allow for replacement of my current propane unit? Can it still allow for a propane line into it? If that makes sense kind of another back up? I would think my existing forces air ductwork in my basement would be sufficient for correct ductwork? Please correct me if in wrong i do not know a whole lot about these units.

 

[maple1]

Unless I had a low heat load, or a small open-design house - I don't think I would heat my house with a space heater as opposed to a central heating unit.

Stihly Dan knows what's up - and not all wood burning furnaces are created equal. Comparing a Hotblast or Vogelzang to a Kuuma is apples to oranges.

 

[tjcole50]

Be nice if the kuuma can replace my propane furnace and act in its place with with a full tank outside for the few times we won't be here for any feeding

 

[STIHLY DAN]

Most likely your ductwork is not up to spec or safety standards for wood heat. ALL of it has to be metal and there are clearances that have to be met. No kuuma does not offer an alternative to wood, They specialize in the one thing and are good at it. You could have an electric coil installed in the duct. The caddy offers a dual fuel furnace that you could replace your old one with. They are also a good unit.

 

[tjcole50]

My duct work is all standard rectangle metal duct? Is a different gauge or something required for wood? Thought these things just tied I to existing plenum?

 

[STIHLY DAN]

They do. You just can't have any flex duct which is often used to get to the vents. Many places have clearance codes, Mine is 6 inches for the 1st 6 ft then 1 in after until the 1st 90*.

 

[tjcole50]

I have seen any flex work at my house but does that really prevent people from hooking these up?

 

[STIHLY DAN]

I have seen any flex work at my house but does that really prevent people from hooking these up?

It should. If power goes out or fan die's the ductwork can get very hot.

 

[tjcole50]

It should. If power goes out or fan die's the ductwork can get very hot.

Completely at the end of the duct runs is the only place I could see flex being used? But all of the visual duct in the basement coming off and including the main trunk is all solid

 

[BoilerMan]

It should. If power goes out or fan die's the ductwork can get very hot.

And poof, you don't have to worry about it any more.................

TS

 

[BoilerMan]

Completely at the end of the duct runs is the only place I could see flex being used? But all of the visual duct in the basement coming off and including the main trunk is all solid

How old is your house? Flex (basically large diameter dryer hose w/FG insulation) has only been used for the last 20 years or so for heating.

TS

 

[tjcole50]

House was built in 76 all solid duct work as far as I can see. Other dude was very persistent that I didn't have correct duct work?

 

[STIHLY DAN]

House was built in 76 all solid duct work as far as I can see. Other dude was very persistent that I didn't have correct duct work?

I'm not saying you don't, but the vast majority of fossil fuel installs use flex somewhere. It's cheaper, easier and faster. Also they don't need to follow the same clearances. Just don't want anything bad to happen for you.

 

[Badfish740]

Most likely your ductwork is not up to spec or safety standards for wood heat. ALL of it has to be metal and there are clearances that have to be met. No kuuma does not offer an alternative to wood, They specialize in the one thing and are good at it. You could have an electric coil installed in the duct. The caddy offers a dual fuel furnace that you could replace your old one with. They are also a good unit.

This is not necessarily true. Your local code/your appliance may vary, but many wood furnace manufacturers simply specify that 250 degree rated flex must be used, and that it must only be used for runs between the main trunk line and the room registers. Below is the language that Englander uses:

NOTE: The warm air supply-duct system should be constructed of materials with a minimum temperature rating of 250 deg. F. Also, the plenums installed to the furnaces are to be constructed of metal.

My Englander is ducted into the rear of my oil furnace plenum. The main trunk (8x14 sheet metal) exits the opposite side of the plenum with the first flex duct line located about 6' from the plenum. My local inspector (who is also a volunteer firefighter) signed off on the install as did my homeowner's insurance company. That said, I needed to install the flex because I had done some remodeling and moved some registers around, so I sourced brand new flex duct with a proper temperature rating. Flex that was installed 20 years ago may not be adequate for wood furnace service. Furthermore, again, the OP's locale may vary, but 1" clearance from combustibles is usually all that's required for ductwork connected to a wood burning appliance, and only for the first 6' from the appliance. My main trunk line was already dropped 1" from the joists-my inspector told me that this was because an oil/gas furnace is perfectly capable of overheating as well and therefore the clearance is needed anyway, so the existing ductwork may be just fine.

I bought my Englander used five years ago and it has served me well ever since. Do I wish it had secondaries? Absolutely, but I have a relatively small house (1100SF) and I use about 5 cords a year, which isn't terrible IMHO. In a perfect world I'd put in a gasser with 1000 gallons of storage feeding panel radiators in every room, but without the existing infrastructure in the house it makes zero sense costwise... After five years I've made my money back on my Englander many times over.

Current location of my propane furnace would be great for an add on which there is a large basement window I can make a chute for wood supply.

Good thinking. I was lucky enough to have a window near my oil furnace. I removed the wooden frame, bricked a thimble into it, and ran the flue out and up the side of the house. My chimney is open to the outdoors but is high enough (28') that I've never had any draft issues whatsoever even when the chimney is cold. I converted another window on the other side of the basement to a "wood chute" which consists of a door on the outside of the house and a bin inside. It's nice to wake up on a single digit morning and simply walk down to the toasty warm basement in bare feet and pull a couple of splits out of the bin rather than throw on boots and a coat and go outside to the woodshed. I have enough room in my bin for about three to four days worth of wood. There are plenty of hearth posters running furnaces and the search function will reveal quite a bit of info if you poke around a bit-good luck!

 

[tjcole50]

Thankyou and understandable stihly! Appreciate concern I will look into these when budget creeps close enough to purchase! The system I have in my head sure sounds good but we all know how that goes come install and $$$ time ha!

 

[brenndatomu]

but 1" clearance from combustibles is usually all that's required for ductwork connected to a wood burning appliance, and only for the first 6' from the appliance.

Nope, 6" for the first 6', then 1" after...here is a screen shot of the duct clearance page out of my Yukon manual. This is standard wood furnace duct clearances right from NFPA code

 

[Badfish740]

Nope, 6" for the first 6', then 1" after...here is a screen shot of the duct clearance page out of my Yukon manual. This is standard wood furnace duct clearances right from NFPA code

I think I see the disconnect here. The Englander hot air outlet fits 8" round duct. I have about 7' of 8" round duct which carries the hot air to the plenum on top of my oil furnace. That satisfies the 6'/6" requirement. Many add-ons (Englander, Hotblast, etc...) are configured in this way. The Yukon is not an add on, it's a combo and is configured differently. That said I was wrong in the way I phrased what I said-I was referring to the existing ductwork in the home.