Moving warm air

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FLINT

Minister of Fire
Dec 5, 2008
535
Western VA Mtns.
Hey guys, I'm pretty new here, and I imagine that this topic has been covered quite a bit. I did a search and found a few things, but thought i would ask anyways.

We have a small ranch house with the woodstove at one end of the house in the far end of the living room. At the other end of the living room, a 10' hallway leads to our bedroom. While we can easily heat the majority of the house into the 70's, our bedroom is usually about 10 degrees colder.

I was thinking of putting in a section of 6" flexible duct above the doorway to the hall, through the hall and out above the door to our bedroom. I was thinking of putting in a small fan out of my old computer to help draw the warm air. I figgured a too powerful fan would cool the air down too much.

OR would it work just as good to just open up the space above the two door ways so that warm air isnt trapped in that space as it is now - and not employ a fan or duct.

OR should I just not waste time and money and wait until next year, when I am planning to buy a nice new efficient stove and install it as close to the middle of the house as I can with a metal chimney.

SO I guess the real question simply is, "does moving warm air work"??????

Thanks!
 
If you have a ranch house and it has a craw space, it is easier to move cold air. You put in a return in the far corner of the cold room and move the cold air to where your stove is. The hot air will move into the cold room. If you use fans on the floor, move the cold air towards the stove. If you are going to replace your stove and relocate it, get a small ceramic space heater for that room and only use it when need. That will hold you over til you get the new stove.
 
Flint,

Good question. You will find lots of information on these forums about moving heated air. So, please search away!

However, my two cents is that heated air normally does not move sideways too well on it's own. However, do try a simple portable fan or two, and in both directions, when your installation is complete. Opening up the highest level will provide for more horizontal flow, assisted or otherwise and with no energy needed.

There are many member contributors that may certainly chime in on this, that is once their power comes back on after the recent storm.

Good luck and keep researching, before you finalize your purchase.
 
My stove guy told me to use ceiling fans blowing down for winter and my forced air furnace fan to distribute the air better. I've got a 1100 square foot ranch with the insert in the center of the house. I need to pick up a couple of thermometers to throw in the bedrooms to see if this works. The 3M filter in the furnace does catch a boat load of ash that is released from reloading and cleaning out when I use the fan.
Also, having the proper insulation will hold the heat in the house to give you the opportunity to move the air. In my region I need a R-value of 49 in the attic.
 
A small fan on the floor in the bedroom doorway blowing toward the room with the stove in it will help. You could also put a pedestal fan in or near the doorway of the room that has the stove, blowing toward the bedrooms. Doing both of these will work very well in getting the heat to the back rooms.

The fans on the floor in the bedroom doorways move the cool air out of the bedroom spaces, when the cool air leaves, the warm air has a place to go. The fan that is elevated (pedestal) helps move the warm air to the bedrooms. The fans don't need to be on high either, the low settings seem to work just fine. Seems to work well at my house and I have to get mine up the stairs and then down the hall into the bedrooms. KD
 
We love our bedroom a good 10* cooler than the rest of the house. Great for sleeping and a good snuggle. If you really need some extra heat for sleeping, an electric blanket or mattress pad works great.
 
Same problem here as well. Ranch house with the bedrooms down the hallway, & the insert at the other end. The room I have the insert in also has a vaulted ceiling. I did experiment with a in-line duct fan I got a HD blowing some hot air from the vaulted ceiling back to our bedroom and it did help some but just not enough. I ordered some larger ones and they just arrived today. I'll post Sunday or so and let you know if it works.

If not I'm going to turn the fan's around so it sucks the cool air from the bedrooms and will force the hot air to flow down the hallway. The only thing I don't like about this is that you will have to leave your door open or cut some vent holds for the air to flow freely.
 
Pinewood's solution, if practical for your situation, will restore a proper convection loop, evening out the heat distribution with no added electricity cost.


Ts
 
Techstuf said:
Pinewood's solution, if practical for your situation, will restore a proper convection loop, evening out the heat distribution with no added electricity cost.

You might want to read it again. It's certainly a credible idea, in fact I've installed such a duct system in my own home, but simply providing a conduit for the air without inducing forced circulation through it won't do a thing. There will be a price to be paid for electricity, because without a fan, it's gonna do zip. Rick
 
i have a similar situation , along while back i learned that its easier to move cold air than hot air , so i have a small desktop fan that sits in an inobtrusive location in my hallway and blows air on its lowest setting back towards the stove on the floor , the air "wants' to move that way anyway with the natural convection loop found in most homes. as a test to see how well the air is moving in and out , take a match or candle cigarete lighter etc. hold it high in a doorway leading out of the stove room. the flame should lean towards the cooler room. now lower it to the floor and the flame leans out of the cool room. we want to inhance this without moving the air too fast and causing too much dissipation.
 
Thanks for the suggestions. Good idea about moving the cold air, I could try that.

I'm not sure though were to put a fan down low that everyone wont trip over it. our hall is pretty narrow.

I think I am going to first open up above the doorways first without a fan and see what happens. We don't have central air or any other heating or cooling system in our house at all. I don't mind it 10 degrees colder in the bedroom at night, but our bedroom is large and is kind of like a combo bed living room, and its not fun to hang out in there during the day when its cold.

I really need to insulate our floors - thats part of the long term plan as well.
 
Techstuf said:
Pinewood's solution, if practical for your situation, will restore a proper convection loop, evening out the heat distribution with no added electricity cost.


T

Do you have a link? I did a search and it found no results
 
My fireplace insert is in the living room of my apartment, the building I own. My bedroom is in the very back, what used to be an "L", connecting to the barn which burned many years ago. Being an old New England farmhouse, it's got red oak floors with little friction. Warm air goes up, and trying to get it to go down is like trying to push water up a hill. Just does not want to go there.

Much easier and practical to push cold air into the room where the warm air is, displacing it. It's like forced ventilation in firefighting. The warm air will cycle along the ceiling until it gets to where the cold air is being displaced from, and then replace it.

It's 27 decent paces from the fireplace to my bed. Living room stays 78 to 85 when the insert is really working, like when it is zero out. Generally remains 68 to 75 in the bedroom.

Since I put the new heating system online, with the wood/coal boiler, I have to admit I haven't used the insert much. I may fire it when it is extremely cold out this winter to help the central heating system keep up. Otherwise, it will be great for between days, when it's cold enough for a fire but not cold enough to burn the boiler.

I just use a floor fan on low, at the end of the hallway to my bedroom.
 
FLINT said:
...I really need to insulate our floors - thats part of the long term plan as well.

That sounds like you do have access to beneath the floor...basement or crawlspace, then. The idea put forward by pinewoodburner's worth a look, then I'd say. Cut a floor register in the most remote corner of the bedroom, run an insulated flexible duct from there to another new register installed somewhere close to the stove, and install a variable speed inline fan/filter into the duct, all beneath the floor, with the fan control located wherever is convenient. Orient the fan to take a suction from the bedroom register and deliver the air out near the stove. Cold air will be drawn from the bedroom floor, and warmer air will find its way in to replace it. Probably no need to tear into the walls above the doors. Rick
 
Flint, I had the same set up as what you described, but with only one doorway, to the master bedroom. What I noticed was a ton of warm air would not make it's way down and under the header above the bedroom doorway. So, I installed one of these room to room fans and it made a huge difference. Our master stays an easy 10 degrees warmer now. The fan uses only 50 watts and moves 160CFM on low setting which is plenty. Just make sure you have about an inch gap under your door for the cold air to push back down the hall for when you want to shut your bedroom door. Here's the link.

http://www.iaqsource.com/product.php/suncourt/tw108/?product=111135&category=885#tabStart
 
fossil said:
Techstuf said:
Pinewood's solution, if practical for your situation, will restore a proper convection loop, evening out the heat distribution with no added electricity cost.

You might want to read it again. It's certainly a credible idea, in fact I've installed such a duct system in my own home, but simply providing a conduit for the air without inducing forced circulation through it won't do a thing. There will be a price to be paid for electricity, because without a fan, it's gonna do zip. Rick


Could you use an outside air kit to suck the cold air from that end of the house directly into the stove? Probably against code but you could skip the fan.
 
Well, that wouldn't really be "outside" air. Rick
 
There will be a price to be paid for electricity, because without a fan, it’s gonna do zip


That could be true, depends on the implementation. Of course we are both making certain assumptions. Me with the word 'practical' and you with the word 'zip'.


The temperature asymmetry of the magnitude mentioned by the thread's author could indeed provide the flow necessary for an adequate convection loop. However the grate size required is somewhat larger than many consider aesthetically pleasing. Having grown up in a house that made use of grating to establish a rather large convection loop, and having slept in one of the rooms furthest from the stove, I can personally attest to their efficacy. The grates we used were about 2x3 feet and my return air grate was just below my bed, partially off to one side. All I had to do was leave it covered with dirty clothes midwinter to wake up in the middle of the night, wishing I hadn't.

To each his own.



TS
 
Thanks for reminding me TS. I just moved my cloths now and I can feel the air moving already. I was wonder why the heat was not moving so well this year :red: I have a johnson energy system hooked into my heater ducts. With one pipe cracked open to it heats the basement and keeps the floors warm. With the warm and cold air fighting to move through the kitchen utility room and up and down the stair well it wasn't moving very well.

Billy
 
fossil said:
That sounds like you do have access to beneath the floor...basement or crawlspace, then. The idea put forward by pinewoodburner's worth a look, then I'd say. Cut a floor register in the most remote corner of the bedroom, run an insulated flexible duct from there to another new register installed somewhere close to the stove, and install a variable speed inline fan/filter into the duct, all beneath the floor, with the fan control located wherever is convenient. Orient the fan to take a suction from the bedroom register and deliver the air out near the stove. Cold air will be drawn from the bedroom floor, and warmer air will find its way in to replace it. Probably no need to tear into the walls above the doors. Rick
I do something similar, drawing cold air that rolls down the stairs under the floor, through the warm crawlspace. The centrifugal fan is in the crawlspace and has two furnace filters on it. It blows this cool air up through the floor directly onto the bottom of the firebox.
 
FLINT said:
Thanks for the suggestions. Good idea about moving the cold air, I could try that.

I'm not sure though were to put a fan down low that everyone wont trip over it. our hall is pretty narrow.

I think I am going to first open up above the doorways first without a fan and see what happens. We don't have central air or any other heating or cooling system in our house at all. I don't mind it 10 degrees colder in the bedroom at night, but our bedroom is large and is kind of like a combo bed living room, and its not fun to hang out in there during the day when its cold.

I really need to insulate our floors - thats part of the long term plan as well.
stoveguy2esw said:
i have a similar situation , along while back i learned that its easier to move cold air than hot air , so i have a small desktop fan that sits in an inobtrusive location in my hallway and blows air on its lowest setting back towards the stove on the floor , the air “wants’ to move that way anyway with the natural convection loop found in most homes.

Mike's suggestion is exactly right. Try it with a standard table fan for a day. You should see a difference within an hour or two. If this works well, here's a suggestion for a fan you can get that won't be tripped over as easily.

https://www.hearth.com/econtent/index.php/forums/viewthread/26587/
 
yes, we do have a crawl space, and I can see how running a duct under the house pulling the cold air back towards the stove would work.

we also do have a palonis ceramic heater that we use in our bedroom if it gets too cold.

I may just wait until I move the stove and see if that solves the problem before I start hacking holes is things.

I'll print this thread and keep all of these suggestions in mind for next winter when I see how things turn out.

Thanks again!!
 
FLINT said:
...I may just wait until I move the stove and see if that solves the problem before I start hacking holes is things.

I think that's the very best idea for now. Use portable fans in the meantime, experiment, whatever, and plan for the future more central stove location & go from there. Rick
 
fossil said:
Techstuf said:
Pinewood's solution, if practical for your situation, will restore a proper convection loop, evening out the heat distribution with no added electricity cost.

You might want to read it again. It's certainly a credible idea, in fact I've installed such a duct system in my own home, but simply providing a conduit for the air without inducing forced circulation through it won't do a thing. There will be a price to be paid for electricity, because without a fan, it's gonna do zip. Rick

Fossil is correct, you need an inline duct fan to move the cold air. Sorry that I left that out. If you have a two story house, a duct will move the air up and down with out a fan. As others have suggested, try some small fans and see if that helps before doing something permanent.
 
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