HVAC Guy Said No Good-Transfer Heat From Wood Stove-

[Mike PA]

Cold air return is a problem, but sometimes that can be accomplished by something as simple as leaving a door open and allowing gravity to work. In that house, all that was present to remove cold air were floor grates, and not in every room. I didn't say it worked well, but it kept the house reasonably warm, you just couldn't expect to heat it quickly if it got cold.

I'm not saying for certain that it will work or work great, but that it may work enough, depending on conditions and expectations.

 

[goof008]

I use my forced air blower to help distribute the warm air. It works pretty well. My stove is in the basement and it keeps the 1st floor at about 74 and upstairs at about 65-68, which is perfect for me.

One thing I was told that works well is blowing cold air across your stove, rather than trying to move the hot air from it...cold air is more dense and you will actually be pushing more air that way, so you should see better heating.

Also, the electricity to use your furnaces blower motor is negligible, especially when you take into consideration the benifit.

Good luck

 

[mga]

I use my forced air blower to help distribute the warm air. It works pretty well. My stove is in the basement and it keeps the 1st floor at about 74 and upstairs at about 65-68, which is perfect for me.

One thing I was told that works well is blowing cold air across your stove, rather than trying to move the hot air from it...cold air is more dense and you will actually be pushing more air that way, so you should see better heating.

Also, the electricity to use your furnaces blower motor is negligible, especially when you take into consideration the benifit.

Good luck

i just recently did something similar. i'm drawing the air from the furthest room and using that to feed the fire place heat exchanger. the air flowing in usually is around 68 degrees and the air coming out varies from 175 upwards to 250...depending on the fire.

my theory was to draw the air out of the room and allow the hot air to flow it's way down to replace it.

so far, it seems to work great.

 

[mtfallsmikey]

Something else to consider: HVAC and furnace people have a particular mindset when it comes to heating. They look at keeping a house at an even temperature and being able to warm a house quickly, which requires more BTUs and better air handling. However, if you are willing to wait and don't expect to have hot air coming out a duct, adding warmer than ambient air to your room will heat the room, but it will take time. You may lose a lot of heat along the way, but where is that heat going? If it goes to living space, that is fine. When I was a kid, we heated the entire house (except the attic), with a wood stove in the basement. It was connected to the air handling system for the furnace and took hot air off the top of the stove. If you let the house get cold, it would take a long time to heat it up, as we moved larger quantities of air, but not at the temps you would get from a furnace. What you suggest could possibly work, just not like an HVAC guy would like.

Adding a plenum to the top of your stove and drawing air from that would help tremendously when trying to heat from a stove (sort of turns it into a furnace).

Yes, that mindset is correct. We have designed and installed enough heating systems to know that fast response, proper heating appliance/ductwork designs keep even temperatures.....meaning comfort. We are also designing systems that use fuels that generate a constant temperature inside of the furnace. That can't be done easily burning wood. Keep in mind when you turn your fan switch on your t-stat to "on", and run it constantly, that the default fan speed may be on high, especially on those with central A.C. You can add a manual switch, even a variable speed control. Sometimes it works, sometimes it doesn't.

 

[tals2]

Something else to consider: HVAC and furnace people have a particular mindset when it comes to heating. They look at keeping a house at an even temperature and being able to warm a house quickly, which requires more BTUs and better air handling. However, if you are willing to wait and don't expect to have hot air coming out a duct, adding warmer than ambient air to your room will heat the room, but it will take time. You may lose a lot of heat along the way, but where is that heat going? If it goes to living space, that is fine. When I was a kid, we heated the entire house (except the attic), with a wood stove in the basement. It was connected to the air handling system for the furnace and took hot air off the top of the stove. If you let the house get cold, it would take a long time to heat it up, as we moved larger quantities of air, but not at the temps you would get from a furnace. What you suggest could possibly work, just not like an HVAC guy would like.

Adding a plenum to the top of your stove and drawing air from that would help tremendously when trying to heat from a stove (sort of turns it into a furnace).

Older 4-square homes built in the 20's use this concept. Rather than a large, long footprint like a ranch style, they built 2 1/2 story houses. An oil (or now wood, in my case) burner sits in the basement beneath a large cast iron grate. Warm air flows directly into the main floor which is the main living area. An open stairwell located near the grate allows warm air to flow upstairs to the bedroom areas.
Result: Main living areas: 68-72
Sleeping areas: 63-68
No fans or electricity needed. But if you let the upstairs get too cold, it will be 4 hours until you are comfortable again.

 

[sesmith]

Beginning to think my only options are...

1. Fireplace insert with fan blower.
2. Get a bigger stove that can make it 90 degrees in that location.
3. Install a stove on other side of house.

Or, 4) put the stove in the cellar.

We had a similar problem when we first moved in our place (27 years ago). I had the stove in one end of the house (kitchen) and the result was an over heated kitchen and a cold living room on the other end. Nothing I tried with fans worked, so I moved the stove down to the cellar. It is below the kitchen on the same end of the house. There is a stairway that goes up to the kitchen. I leave the stairway door open. The furnace (forced air) is on the other side of the cellar. I leave the blower door open...cold air from upstairs returns to the cellar there. I do use a small fan in the kitchen doorway and a ceiling fan in the kitchen to send some warmer air toward the living room on the other side of the house. I also stacked cinder block walls on either side of the stove, about 10" away from it and just a little higher than the top of the stove, to serve as thermal mass and help keep the stove from just radiating all it's heat out the cellar walls. The 1st course is laid sideways to allow airflow under and up the wall between it and the stove.

This setup works ok for us...much better than having the stove upstairs, but it's not ideal. Ideal would probably be to have a 2nd small stove in the living room.

 

[Bushmans]

I have a bi-level with a fireplace in the lower level. 1800 sq ft.
This is my first year in the home and I am trying to heat with the fire as much as possible.
At first I put a box fan at the end of the fireplace room and blew the warm air up the steps into the main living area. Worked good until the temps dropped.
So I took an exhaust fan for a bathroom (very quiet one) and installed it in the ceiling of the fireplace room. I tied it into a 3 inch flexible duct and cut a hole in the cold air return downstairs and snaked it through to the upstairs where I secured it to the faceplate of the return. I took care to seal around the hole downstairs. Total run of about ten feet. The fan in the ceiling is a low profile and unless I point it out no one sees it.
When the fireplace room heats up downstairs I flip a switch on the wall and the exhaust fan comes on and sends warm air from the ceiling directly into the main living room upstairs.
This helps me by pass the heat traps like doorway heights and tall ceilings. There is a lot of heat in the top foot or so of your room you just have to get it under the door opening.
Sure I could have cut a hole in the floor and installed a grate but Momma and I didn't want that.
A digital thermometer placed through the return faceplate directly into the three inch duct reads 88 to 90 degrees. The CFMs coming through the duct are not that large so the room stays comfortable. 67-70 degrees. It is an open concept area so the kitchen and dining room stay that temp too. That is from a fireplace mind you. I will be installing a wood stove insert before next winter. This should greatly increase my temps and lower my consumption of wood.
Right now it is fun trying to optimize your burning!
If your wondering how long it takes to warm the house it would be a long time using only wood so I initially run the furnace for about 15 minutes or so to bring the house up to temp and then let the fire take over.

 

[rider93hawg]

Cut a fat hole in wall and put a big fan up there to distribute the heat. I may sound like a tightwad moron and I well could be one, but I did it and it works great! :smile2:

 

[Whitespider]

Fighting a lost battle.

These threads are exactly why I stopped using “space heater” type wood-burning appliances years ago. A stand-alone stove is great for a one-room cabin, fishing/hunting shack, garage/shop and the like, but really is silly for multi-room home heating. Even when used for supplemental heat they fall short because often the stove is placed in the same room as the existing furnace thermostat, causing the remaining spaces of the house to “go cold”.

I’ve “been there, and done that”… and it’s a lost battle. I’ve done the draft-causing fan thing, left doors open, and none of it is ideal… A wood-fired furnace (or add-on) is the only way to heat the whole house efficiently, effectively, silently and draft-free. It’s still possible to keep the bedrooms cooler than the great room simply by adjusting how far open you leave the vents. What I hate most about stand-alone stoves is that the room they get placed in will always be “hot”, too damn hot, while the remaining spaces of the house become progressively cooler, eventually too damn cool. I like walking comfortably, barefoot and in shirtsleeves, from one end of the house to the other without noticing drafts or significant change in temperature. The time and (especially) money spent adding fans, ducts, vents, and whatnot could just have well been spent on a wood-fired furnace in the first place. You can keep your glass doors, watchin’ the fire ain’t worth it… besides, it’s too damn hot in there to enjoy watchin’ it.

The OWB boys took that concept a bit further… but I like the “feel” of wood heat, and that is lost with an OWB.

 

[Whitespider]

Del, there just ain't any way you'll ever convince me that it doesn't get progressively hotter as you move closer to the stove... I don't care how "open" the floor design. Dad's house is an open floor design log home, with a stand-alone stove... and there ain't any way around it... it gets hotter and hotter as you move toward the stove.

 

[PA Plumber]

We use a stand alone wood appliance and are mostly happy with how it works. We are heating a basement plus two levels up from where the woodstove is located. It actually does a very good job until the temps get in the mid twenties and lower. Then we have to turn on the central air fan.

Would it be better with a wood fired forced air furnace? Sure, but this set up is working and it's nice only using 25, or so, gallons of fuel oil per heating season.

Likely we do have a unique heating situation. The basement steps are in the center of the downstairs part of the house. We take the basement door off in the winter, and for some reason, get very good natural circulation through both upper levels of the house.

30 degrees F out now and 73 deg F in the center part of the 1st floor.

 

[dustytools]

We heat our entire home which is a doublewide trailer (roughly 1600 sq. ft.) entirely with a stand alone wood stove. The room that the stove sits in is roughly center of the house. I can keep temps in that room around 75 degrees and the bedrooms at around 66 degrees which is comfortalbe for us. My idea when I installed our woodstove was to burn a little wood on weekends and evenings to kinda keep the electric bill from being too overwhelming in the winter months and to have a backup heat source when the power goes out, and when you are on a rural electric co-op the power seems to stay out for days at a time during our occasional ice storms. Needless to say that when we started heating with the wood stove for part time use it turned into a full time heating source for us and it has worked out well for us and our situation. Its kinda nice to know that when the power decides to take a dump for a day or two that we will still have a warm house, hot food and hot water. Cheers everyone.

 

[Wagnerwerks]

I think if you can get cold air to move backwards towards the stove you are better off, and the warm air will find its way to where you are taking the cold air from. I didn't go that route, since I had no way of running all this stuff through the basement ceiling. I suppose I could have run my air the opposite direction with the set up we made, and brought the cold air back to the ceiling of the living room and the warm air would have worked back to the bedroom, but that wouldn't work as good when the door is closed to that room.

This is the way to go. Use 6 inch with a pusher fan box and have a feed right above/beside the wood stove. Run the return to the outside edge of the farthest area from the stove and it will "pull" the hot air to the rest of the house via hallways and such.

 

[kentuckydiesel]

It was 15* last night with a 0* wind chill and we were fine with only our wood stove in our 120 year old farm house...which is very poorly insulated.

Here's what I'm doing:

Our house is basically a square shape with three rooms on the back, two on the front, three rooms upstairs. Our wood stove is in the middle back room. The two side back rooms are heated fine with no additional air movement.
To heat the front rooms (which we are currently remodeling...I can feel the cold air coming through the floors/bottom of the walls) I have a box fan hanging in the top corner of the door between the front and back sections of the house. It blows warm air into the cold side of the house, and the cold air returns into the warm room underneath the fan. (This has worked much better than having the fan on the ground blowing cold air into the warm room.)

Also, in the room where the wood stove is, I have a ceiling fan pulling air upward to keep things stirred up, and a small fan blowing air across the stove, just to increase heat transfer.

It's interesting to see, but with the humidifier running in the front rooms, I can actually tell that the air is circulating through as if it was on a track. Works great for us!

-phillip

 

[CrappieKeith]

Stoves can certainly be house heaters though they are not ideal house heaters. You will never get the whole house to the same temp with a stove alone which I think is actually fine since who wants to sleep in a 75 degree bedroom. My 1700 SF single story home is long and narrow and the stove room/living room is in the middle. We run it as high as 70-80 in that room (really enjoy this) and the bedrooms run 65-70.

If this is not acceptable, like if we need warmer bedrooms, then each room is equipped with independent programmable thermostats and electric wall heaters.

The wall heaters are like old baseboard heaters and are extremely effective zone heaters. I would pop these in before screwing around with ducts to move room temp air.

You live in a much warmer climate...the OP should keep that in mind when reading this and other posts.

 

[CrappieKeith]

Fighting a lost battle.

These threads are exactly why I stopped using “space heater” type wood-burning appliances years ago. A stand-alone stove is great for a one-room cabin, fishing/hunting shack, garage/shop and the like, but really is silly for multi-room home heating. Even when used for supplemental heat they fall short because often the stove is placed in the same room as the existing furnace thermostat, causing the remaining spaces of the house to “go cold”.

I’ve “been there, and done that”… and it’s a lost battle. I’ve done the draft-causing fan thing, left doors open, and none of it is ideal… A wood-fired furnace (or add-on) is the only way to heat the whole house efficiently, effectively, silently and draft-free. It’s still possible to keep the bedrooms cooler than the great room simply by adjusting how far open you leave the vents. What I hate most about stand-alone stoves is that the room they get placed in will always be “hot”, too damn hot, while the remaining spaces of the house become progressively cooler, eventually too damn cool. I like walking comfortably, barefoot and in shirtsleeves, from one end of the house to the other without noticing drafts or significant change in temperature. The time and (especially) money spent adding fans, ducts, vents, and whatnot could just have well been spent on a wood-fired furnace in the first place. You can keep your glass doors, watchin’ the fire ain’t worth it… besides, it’s too damn hot in there to enjoy watchin’ it.

The OWB boys took that concept a bit further… but I like the “feel” of wood heat, and that is lost with an OWB.

I could not agree more....a guy will do what a guy will do...and he will get used to the outcome no matter how well it really works.

 

[blackdogon57]

"The OWB boys took that concept a bit further… but I like the “feel” of wood heat, and that is lost with an OWB"


I installed my OWB a couple of years after installing a freestanding wood stove on the main floor of my 2800 sg foot house. I still fire up
the wood stove quite often when it gets really cold outside. I like my hot area in the living room where the stove is. Nothing like radiant heat
to warm the bones.

 

[greengiant]

Man, Just when a guy thinks he knows what his heating set up would be in his dream house you all start making it confusing again:smile2:

 

[logbutcher]

Another Approach-Don't Heat Where You Sleep !

Most of northern Europe's home are not centrally heated. Bedrooms without plumbing are kept cool.
The first assignments in Norway and Switzerland were some shocking for us : they didn't heat bedrooms. We're talking Alpine regions and above the Arctic Circle. Windows were usually opened at night for "airing" , and thick ( e.g. 1 foot ) down comforters and flannel sheets made the beds cozy. No stoicism.

We do that now, and have done it for years in northern New England. And, hey, it's romantic for you few available for such. :hmm3grin2orange:

Healthier for you it is said and for the kids to spend the 1/3 of the day in open fresh air. Why breathe heated air in dreamtime and more...................?

 

[Chris-PA]

Heating a house and having every room be exactly the same temperature are not the same thing. I have a cheap stand alone stove in my basement (a living space too), and I can use the blower from my old oil fired furnace to circulate the heat. It pulls the heat off the top of the basement and blows it around the house. I run it with a cheap thermostat in the basement, so when that room gets hot the blower kicks on. It's running now, and working fine. By morning the stove room will cool down below the 80deg setpoint and blower will be off The basement is much warmer than our bedroom 2 floors up and over at the other side, and the other rooms vary in between. So what? The house is comfortable, and if you are too cold or too hot you can move too a room that suits you better, or adjust your clothes appropriately. Honestly, I've never liked perfectly uniform heat. My living room is 66 right now, which is plenty warm. And if it's really cold out or I want more or just the ambiance of a burning fire upstairs, I'll light the second stove up here.

The downside of running the blower is that the air that comes out of the ducts does not always feel as warm as it would from a oil or gas fired system. So don't stand in front of the vents. Also, the blower uses more power than I would like, so I don't always run it and I will eventually put in iron grates to allow better convection. Our bedroom will get a little colder then, but as long as it stays over 50 that'll be fine. We've got a parabolic dish radiant electric heater up there if we want instant heat.

You guys can have your add on furnaces and OWBs - every time I read about them I'm thankful I don't have one. Complexity has a cost I'm not interested in paying. If the power goes out (which it does here a lot), it doesn't matter. My simple EPA stoves will quietly heat my home as cosy as I need, purely by radiation and convection.