How to Move Hot Air From One Room to Another

[JGaulard]

Our first winter in our new house was a challenging one. Not too far into it, we experienced a very cold front and woke up to frozen pipes. When I say frozen pipes, I mean frozen pipes. Everything. From the baseboard heat to the shower to the washing machine. Nothing worked. Needless to say, I spent that entire day with a torch in my hand making repairs. While I gave myself a hearty pat on the back that night for being so handy around the house, I vowed to never let that happen again. Shopping for wood stoves I went.

Months later, Laura and I made a visit to Home Depot to pick up a mammoth beast of a stove. We bought it and I installed it. At that point, I was actually looking forward to the cold weather so I could test out its operation. It didn’t take all too long for that to happen. The next winter arrived and we were snug as bugs in rugs.

Since then, things have been great. Our wood stove produces heat like it’s nobody’s business. I primarily run it on the cooler side because it’s rather large for the smallish room it’s in. Since it would have been exponentially more difficult to install it in the main house, I put it in a side room that measures about 400 square feet. My thinking was that I could put a fan in the doorway to pull the heat from one room to another.

Well, as things turned out, I’m sort of still working on the moving the heat between rooms thing. See, we’ve got a unique setup here. The room I installed the wood stove in has about six stairs (up) that lead into it. It also has an intermediary room between it and the main house. Because of this configuration, any air I blow out or in circulates in the intermediary room and doesn’t have nearly the effect I thought it would have on the other section of the house. Take a look at the fan I set up.

How to Effectively Move Warm Wood Stove Air From One Room to Another​

This is a high velocity fan that I’ve mounted to the top of the doorway of the warm room. As you can see, it’s facing on a downward angle and there’s a wall in front of it. That angle leads down the stairs and into the main house.

For the past two years, I’ve messed with this fan. I placed it on the floor blowing both directions, on the top of the stairs, bottom of the stairs and in between. I even got a six inch duct fan with a long tube that travels from room to room. None of these “solutions” gave me the results I was looking for. Don’t get me wrong, they moved air and heat certainly did travel, but when I read that a particular fan moves 900 cubic feet of air per minute, I want it to move that much. And I want to feel it.

Recently, we experienced another cold snap. I think this one covered most of the good ol’ USA. Two nights during this cold snap, the temperature dropped down to about -15 degrees. Needless to say, no matter how much heat someone’s got going on in their house, there are going to be at least a few issues. Our situation was like this: we had one really nicely heated room with a house that was otherwise chilly. If we didn’t have this wood stove, the neighbors would have found Laura and me frozen like ice cubes in bed. Probably in about two years, which is concerning. We don’t communicate with the outside world much, which is a story for another time.

Anyway, as I walked my sweat covered body out to say hello to Laura’s purple half frozen body, we came to the conclusion that our situation needed to be rectified. We either needed to install another wood stove in the main section of the house or finally figure out a way to get the heat from the warm room into the cool ones. Much consideration was given and after a few hours of thought, I decided on the latter. We have an abundance of heat. All we needed to do was move it.

My latest idea was to purchase another fan. This time, instead of getting an 18″ one, I got a 14″ inch one. If you’re experienced with these types of high velocity fans, you know they move a lot of air. I mounted this one at the top of the doorway that leads out of the intermediary room.



Here’s my idea. The big fan blows the warm air from the warm room into the intermediary room. Then, the smaller fan blows that warm air into the rest of the house. Both fans are mounted to the tops of the doorways, so the cooler return air should come across the floor. That’s my hope anyway. And as I sit here and write, it seems to be working. I’ve got only one fan on and cool air is pouring into the room, which means the hotter air is leaving.



I swear, I could solve this issue in a heartbeat of that intermediary room wasn’t there. Moving warm air from room to room is easy, if all that’s in the way is a doorway. Having two doorways throws a monkey wrench into any operation.

Let me ask you a question. Do you have a wood stove? If so, do you face a challenge that’s similar to this? I’d love to hear all about it, so if you wouldn’t mind, please leave a comment below telling me your story. Thanks for reading!

 

[CampFireJack]

I have a woodstove in a 20′ x 20′ lean-to that is on the side of my house. There is only 1 doorway going from the kitchen to this lean-to. I have my woodstove right inside the doorway. My problem is that this lean-to has a loft and the loft has a 7′ ceiling, so the entire lean-to is 15′ high. the loft floor is boards that are spaced apart somewhat. the loft has a door leading into the upstairs bedroom. overnight i shut the door going into the kitchen and open the door into the bedroom and it heats it very well. The problem i face is during the day when i try to heat the rest of the downstairs… the lean-to and loft get exceedingly warm but the kitchen is like 10* cooler. I am not sure how much a fan at the top of the doorway would help since all the hot air is going up into the loft. I thought about mounting a ceiling fan above the woodstove to try to keep the hot air down? Any good ideas? It don’t get very cold is the area. Maybe 5-10* at the coldest. But my house does not have very good insulation since it is an old log farmhouse. Can’t wait to get some ideas.

 

[JGaulard]

I totally understand where you are coming from with this problem. I had a similar one and a floor fan worked well. The floor fans push a lot of air around and they’re good at moving it in the direction you want. What I would personally do is sit the floor fan in the downstairs doorway between the two rooms pointing at a 45° angle upward into the side room where the stove is. That will push the cold downstairs air that’s sitting on the floor into the hot part of the warm room, which will push that warm air down and out the downstairs door. Your goal is to actually move the air from one room to another. Displacement, if you will. The floor fans are great at that. Here’s a link to a good one on Amazon: https://amzn.to/3fGiXEv.

 

[CaptainDan]

I agree, I have a fan blowing cooler air from my hallway into the Woodburner room (which gets very hot). This works better than trying to blow the hot air out through the doorway into the hallway as it is working with natural aircurrents. What I would like to know is if a Woodburner top heat driven fan would improve the flow of hot air into the hallway from my heated room.
Interesting subject. Thanks.

 

[JGaulard]

I don’t think those top fans work very well. My friend has one and he says it hardly moves any air at all. I’ve always wanted one, but I think they’re more wishful thinking than anything else. A true electric fan is the only thing that works.

 

[WendyMay]

My room is 18 by 24 that is where my stove is its also an addition to rest of my home but my home has duct 16 by 4 inch rectangular in the floor which has insulation and covered underneath with thick cardboard like material when my furnace goes on it heats the insulation in the floor and air is evenly distributed because the floor now is warm and hot air rises and now flows back downward OK but now my wood stove is on and in that addition room has to come out it does with a small fan but needs a lot a heat to warm everything down range and remember now the furnace got no heat going threw the rest off the house so floor is cold it seems cold air is pushing my hot air already rising to ceiling so i installed a i installed a 6 inch round flexible pipe to one off my register with a fan sucking the wood stove heat out off the wood stove room to the main structure with duct keeping the floor warm and the hot air distributing itself all over . so get some small galvanized duct under neath with insulation to warm floor first then run your wood stove heat in the duct after floor is warm the heat will radiate all over your house.

 

[LukeLewis]

How to Get Wood Stove Heat From One Room to Another​

I set my wood stove up in a small room that's on the side of my house. It measures probably around twenty by twenty feet square. The room sort of looks like a lean-to. It's right off my kitchen and there's one downstairs door into the room. I set the wood stove up so it's right next to that doorway on the bottom floor. There is also a loft in this side room and together, the room height is around 15 feet. There's another door upstairs in the loft that leads back into the upstairs portion of my house.

The floor boards of the loft area have spaces between them, so the heat from the wood stove flows upstairs very nicely. Before we go to sleep for the night, I go downstairs and shut the downstairs kitchen door and open the upstairs loft door. The wood stove heats everything really good upstairs. The challenge I find myself facing is one where all the heat from the stove seems to want to go upstairs and not downstairs. Even if I keep the upstairs door shut and the downstairs one open, the heat still remains in that room. As you can imagine, the loft area gets pretty hot while the kitchen stays pretty cool.

I'm trying to figure out how to solve this problem. I think there is too much heat at the top of this room for a door fan to work. Those fans are too small. Plus, since all the heat is at the top of the room, a door fan wouldn't even be reaching it. Maybe a ceiling fan in the loft area to push the heat back down? Does anyone have any good ideas for me? The area in which I live doesn't get exceedingly cold - maybe 5° to 10° in the middle of winter. Another problem is that my house doesn't have good insulation. It's an older farmhouse and it leaks cold air a lot. If you can think of anything that might help me, please let me know. I'd like to get the heat from that room into the kitchen so I can heat downstairs somewhat. Thank you.

 

[CraigHardy]

I've burned wood in wood stoves for a long time and I can honestly say that the only way to get the heat from one room to another is by way of a good floor fan. I've actually had issues where the heat from the stove didn't even make it across the same room, much less another room. Doorways are real challenges for heat to move through, so what you need to do is use a fan to get that heat moved around. Years ago, I bought a fan from Amazon. I forget the actual size. The first one I bought was around 20", but that was too large, in my opinion. I think the second fan I bought was around 14" or 16". I liked that one better because it was quieter and it seemed like it pushed the air more directionally as opposed to spread out all over the place. Here's a link to a random fan on Amazon that I just found. This is the type of fan I'm talking about: https://amzn.to/3fGiXEv.

As far as the best direction to point the fan, that's something you'll need to figure out through trial and error. I would guess that you'd want to have the fan on the floor downstairs sitting right in the doorway. You can point it up so it pushes the cold downstairs air up into the loft area. If you do that, the hot air will need to move out of the way and it'll most likely flow out that downstairs door into your kitchen. That's the hope anyway. I've pointed my fans in all directions and have found some pretty good solutions, but overall, the fan is the only solution. Wood stove heat notoriously moves very slowly if left to its own devices, so you really do need to force it around mechanically.

 

[CampFireJack]

I've got an electric fan that blows the cooler air from the floor into the room where my wood stove is situated. That room gets really warm. I've found that this strategy works better than attempting to blow the air out of the hot room (where the wood stove is). If you think about it, the warm air is already naturally flowing out of the top part of the door and the cool air in the bottom. I'm just helping those air currents along with the fan.

What I've always wondered is if those non-electric fans (powered by heat) that are available to sit on top of a wood burner would help at all. Do you think that would help move the hot air around at all? I find this subject quite interesting.

 

[CraigHardy]

I suppose if you got your hands on one of those fans that was powerful enough, you could theoretically move the air around the room a bit more. I don't think it would help get that hot air out of the room though. At best, you'd swirl it around. But that might disrupt the natural air current you were talking about.

I've seen those heat powered fans in action and I have to tell you that I wasn't impressed. They hardly move any air at all. If you truly have an issue with neat not moving from one room to another in your house, you need to take action. The only way to do that is with a good floor fan. I've tried everything and that's the only thing that seems to work.