Building a new house next year, looking for opinions on indoor wood furnace

[04RevX]

Hey guys...I've been buring with wood my whole life but with a wood stove. I'm in the early stages of research into indoor wood furnaces. The only reason i'm considering going with a furnace is for heat distribution throughout the whole house. The new house will be a colonial close to 3000 sq ft. My thought is to have the wood furnace piggy back with the gas furnace, all pushing through a forced hot air system. I am still going to have a wood burner (most likely a zero clearance fire place) on the 1st floor, but it won't be the main heater. We want to keep a lot of the mess that goes along with wood burning to the basement.

So, I just don't know enough about wood furnaces. I'd love to see what some of you are running and your experiences. The do's and don'ts and the "would do it this way next time". Any help or guidance you guys can provide would be excellent. Thanks in advance.

 

[JP11]

really? a furnace not a boiler?

in slab heat, then low temp designed emitters on second floor. That's how I'd go new.

Small 'boiler room' off the house. no door direct into garage from there. have enough space for water storage and a cord of wood.

if you don't have your own wood lot.. I'd really look into one of those great new pellet boilers. small footprint and don't need a backup.

lots of options. lots of reading on here. bounce ideas around.

JP

 

[04RevX]

Well my thought with going with a furnace as opposed to a boiler was because I'm going to be using the ductwork is going to be there anyways for the AC. But again, I'm early in the research phase so I will look into everything. I'm trying to do this as efficiently as possible but I will spend the money it takes now if it makes the most sense. This will be my forever home...I'm google-ing low temp designed emitters now. never heard of them before.

 

[JP11]

many ways to 'skin' this cat. depends on what you want. My old home had very cheap forced hot air. I hated the noise, dust, and comfort level. I was determined to have radiant everywhere, which I did.

all comes down to your situation. the research part is great. LOTS of ideas on here. keep reading!

JP

 

[maple1]

I think I'd seriously consider a hot water heating system (in-floor and/or low temp baseboard/panel rads), and ductless (mini-split) heat pump(s) for a/c and some shoulder season heating, if starting from scratch.

I just have an aversion to ducts & ductwork in general - and nothing beats radiant heat if you're in a colder part of the country/continent. And I think you are?

Going from there, fuel supply would be based on your local situation. Wood, natural gas, electric, and/or pellets. I also like redundancy & diversity.

 

[JP11]

Maple.. I very much agree. I SO wish I did mini split for AC.

I have THOUSANDS in my hi velocity system. I'm still lacking the air handler and outside unit for the home. My wife's studio is set up completely.

Here's how I'd stack up the options.

If you have acreage and WANT to cut wood. Cordwood.

Then Nat gas if available.

Pellets if neither of above (pellet boiler is where it's at IMHO.) but I've got a woodlot, and a job where I don't get any exercise, thus using cordwood for now.

Buy cordwood.

Propane

Heating oil.

If your'e really a greenie, and have the capital to invest.. Geothermal would fit in there. If money wasn't an option as much on the front end.. A solar drain back system for DHW could go in there for off season use. There's lots of long term savings in here. It comes down to how much planning and money you're gonna put in on the front side.

JP

 

[M1sterM]

We came close to building a house a couple years ago. At the time, I wanted to install a PSG Max Caddy, with an electric heating element as backup (cheap electricity here). If for some reason I do end up building a house, I'd still go that route.

I installed an Englander "Add-on" furnace in my last house, but as a stand-alone unit. I loved it (despite a couple small quirks). One reason for going with the PSG would be the option of adding central air (along with heating more area, multi-speed blower, etc).

 

[brenndatomu]

PSG/Drolet makes the caddy line and the new Tundra furnace, all good options. I think my first choice would be a Kuuma Vaporfire though, https://www.hearth.com/talk/threads/kuuma-vapor-fire-100-wood-furnace-results.112796/ unless like these guys already mentioned, you can spend the big $, go radiant hot water. If you do go forced air, put in a separate fossil fuel burner (gas, oil, whatever) that way your A/C can be run through it...my 2 cents

 

[04RevX]

Guys...good stuff so far I really appreciate it.

I'm a cord wood guy. Have never had to purchase it thankfully with plenty of available acres to harvest down the road. I'm not interested in geothermal right now due to upfront cost. Honestly a forced hot water baseboard system sounds excellent and efficient to me. I neglected to consider mini-splits but I see the value. I'm an electrician by trade but do 99% commercial/industrial so I don't know what the latest trends are in the residential world. I like the control you would have with the mini-splits for AC. A gas line is already at the house site which in my area is the cheapest fossil fuel.

Thanks again for the info. I hope more can chime in.

 

[STIHLY DAN]

Guys...good stuff so far I really appreciate it.

I'm a cord wood guy. Have never had to purchase it thankfully with plenty of available acres to harvest down the road. I'm not interested in geothermal right now due to upfront cost. Honestly a forced hot water baseboard system sounds excellent and efficient to me. I neglected to consider mini-splits but I see the value. I'm an electrician by trade but do 99% commercial/industrial so I don't know what the latest trends are in the residential world. I like the control you would have with the mini-splits for AC. A gas line is already at the house site which in my area is the cheapest fossil fuel.

Thanks again for the info. I hope more can chime in.

Mini splits are a space heater like a wood stove. You WILL have cold spots, (bath rm kitchen) They are great for ac and shoulder season heat. dec, Jan, Feb, you will need, want more heat. For wood Furnaces get a good one that uses little fuel, and is easy to use. I use the Kuuma and spend 3 min a day on it.

 

[04RevX]

Thanks...3 mins a day?? That's fantastic. What manufacturers do you guys recommend for indoor boilers?

 

[M1sterM]

Mini splits are a space heater like a wood stove. You WILL have cold spots, (bath rm kitchen) They are great for ac and shoulder season heat. dec, Jan, Feb, you will need, want more heat. For wood Furnaces get a good one that uses little fuel, and is easy to use. I use the Kuuma and spend 3 min a day on it.

Yeah, but the Kuuma doesn't have a glass door! When I got the Englander, I though the glass door was just a nice perk, but after getting used to having it, I can't image not. It's one thing to drive the furnace just by watching the temps, but it's something else to actually see how the fire is behaving, and opening the door makes it behave completely different.

 

[Spinny]

RevX,

I have a system very similar to what you are looking for. I have a geothermal system with a hitzer wood furnace tied into the plenum. I would hands down install a geothermal system before a minisplit system. Around here you would get way more money in a minisplit system. Keep in mind that right now the government has a 30% tax rebate on installing a geo. That means you can get 30% off you ductwork, your new well, etc. Basically anything that in necessary for the geo to function can be written off. The upfront cost is high but they are incredibly efficient.

I have a new, well insulated 4000 sq ft of space that I am conditioning. Here in Indiana the most my electric bill was this summer was $140. And you can freeze yourself if you want. Doesn't cost any more with the geo to keep it cool in the summer.

YOU NEED A ZONED SYSTEM! TRUST ME! I have 4 zones in my house. Each zone is on its own stat. That way you can custimize the heating cooling in your house.

My wood furnace is controlled by my thermostats and will deliver hot air to each zone as needed. I have it rigged up so that if my wood heat ever falls behind by more that 2 degrees my geo will kick on to help it out. Having the furnace controlled by the thermostats is super efficient. I just started burning for the season and get an easy 16 hour burn. It is very efficient for burning wood.

My biggest "problem" is that I can't really burn until the highs are below 30 degrees or I'll cook myself out of my house and the furnace doesn't want to burn enough which makes creosote/wasting wood an issue. The beautiful thing is that the geo costs so little to run that it isn't worth burning wood until it gets that really cold anyway.

Give me a sec and I'll post how it works by copying a different post from another forum.

 

[lampmfg]

Yeah, but the Kuuma doesn't have a glass door! When I got the Englander, I though the glass door was just a nice perk, but after getting used to having it, I can't image not. It's one thing to drive the furnace just by watching the temps, but it's something else to actually see how the fire is behaving, and opening the door makes it behave completely different.

I'll substitute the much better efficiency and emissions for seeing the fire but I might be biased

 

[Spinny]

Hitzer wood/coal furnace with 4 ton Geo.

4 Zones: Basement - 1st Floor - Second Floor - Bonus Room (550 sq ft) Each has its own stat.

Normally geothermal units run off 3 stages depending on the temp difference between the desired temp and actual.

1st stage geo (+/- 1 degree)
2nd stage geo (+/- 2 degrees)
Emergency Strip Heat (Kicks in after 2 degree difference)

I have a toggle switch that accommodates the wood furnace and changes the stages. I just flip the switch during times that I'm burning wood.

1st stage wood (+/- 1 degree)
2 stage geo (+/- 2 degrees)
3rd stage geo (Kicks in after 2 degree difference)

This is sweet because if its too cold and the wood cant keep up the geo helps out. (Not likely with the insulation I've got) Also nice if you are burning and the fire burns down to low or goes out the geo will kick in and you'll never know the difference.

Blower on wood furnace is wired together with blower on geo so that once the fire starts both blowers kick on together.

 

[Spinny]

AUTOMATING WOOD IS DANGEROUS! ONLY ALLOW A SEASONED PROFESSIONAL TO INSTALL A SYSTEM LIKE THIS! THERE ARE KEY SAFETY FEATURES THAT MUST EXIST TO OPERATE SAFELY!

If power goes off the motor that opens/closes the damper is spring driven and will automatically close when no power is present. There are also air sensors on the geo plenum that will close the damper should the air temp reach x temperature.

Bi-coil stat triggers blowers to kick on. Bi-metal coil expands inside and triggers it.

When the stat calls for heat the zone panel tells the small motor at the top of the picture to raise. This opens the damper at the bottom of the chain. When stats are satisfied the motor lowers the damper. (if all stats are satisfied the damper closes but the zone dampers all open and it blows air to the whole house.)

This system only works well on cold days. There is always some air getting to the fire so it doesn't smolder through holes on front of stove. This works great with the geo because the geo is so cheap to run during mild weather it isn't worth it to waste the wood.

4th pic is of the duct damper each zone has.

 

[sloeffle]

I have a geo ( Waterfurnace ) and wood burning furnace ( PSG Caddy ) setup similar to what Spinny has. I however do not have all of the fancy controls and zones like he does. I am a little jealous of his setup. Forced air is the norm in Ohio, so we have to work with what we are given. I am heating / cooling 50% more square footage with my geo system for the same cost as a conventional propane furnace / AC setup. The geo will also heat your water for you in the summer time.

Having been in a few houses with in slab heating and always having cold feet that is the way to fly IMHO. The problem with forced air IMHO is the constant off and on cycling. I know the newer furnaces eliminate a lot of this by running longer with cooler temps. The temperature swing with a wood furnace are even worse. I would also recommend installing a humidifier with your wood furnace if you are going to go down that route as the heat is very dry. That is on my to do list.

If money were not an object I would get a Winhager pellet boiler with lots of storage and a geothermal system for cooling and shoulder seasons.

 

[iceguy4]

I'll bet you have never spent a winter in a NON hot air heat house. IMHO that dry heat is so uncomfortable compared to hot water or steam heat. Now central AC is real nice too! BUT after living 50+ years with hot air heat I am in LOVE with my old school cast iron radiators (sand blasted and powder coated...smooth like a porcelain bath tub) combined with a HW boiler. I have the knowledge and resources to put in central AC kinda cheap...but I have found for the short season here combined with the fact that 2 very small window units handle one bedroom(just me and the Mrs. now) and one other does our den.. The only thing I would add in a zoned HW maker for winter and a heat pump HW heater for summer...

 

[Spinny]

Good points here:

The geo will also heat your water for you in the summer time.

True, you won't have to pay for hot water in the summer but you do have to hook it up to your water heater to take advantage of this.

The temperature swing with a wood furnace are even worse.

My setup will keep the temp at exactly what I have it set at besides the basement where the wood furnace is unless its 40 degrees out in which case it will put out to much heat.

I would also recommend installing a humidifier with your wood furnace if you are going to go down that route as the heat is very dry. That is on my to do list.

Same here. The stand alone units aren't cutting it. I'm having one installed onto my ductwork so I don't have to mess around with filling the thing up. Burning wood will dry the house out fast.

 

[tjnamtiw]

You've got a lot of good advice there! One additional consideration to supplement the heat PLUS link into your 'colonial' theme is a wood/coal fired cook stove. They have become extremely popular and add a real touch of nostalgia and a desire to tinker and cook. Look at the stoves at www.sopkainc.com. I have one and love it! Geno, the owner, is EXTREMELY easy to deal with and work out a bottom line.