Room to Room OR Doorway Fan?

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I installed my room to room fans tonight. Took me about an hour. I'll report back with how they work.
First night using these fans and this is the first time ever that all my rooms are the exact same temperature. Holding steady at 70 degrees. I'll temp it again tomorrow during the day because it is supposed to get real warm here.
 
Are those fans suppling two rooms?
 
So your just taking hot air into the rooms not using any cold air towards the stove room?
 
So your just taking hot air into the rooms not using any cold air towards the stove room?
For the most part yes. I don't have a stove though. I have a wood furnace located in my basement that is forced air through my duct work. My issue was my main living room which is in the middle of my house is always really hot summer "even though I have central air" and winter, while the rest of the rooms are very cold. I am blowing the warm air into the cold rooms and the cold air I noticed circulates back into the main living area under the door ways. I hope this explains how it is working.
 
Are you saying take the cold air from the cold rooms and push it to the stove?

Jumping in.

Do this. Take strips of toilet paper and tape from the ceilings and door jams. Then turn the fan to push the cold air toward the stove. Watch the toilet paper which will show you the current flow.

Pushing the cold air adds multiple degrees to my further rooms.
 
Yes, you can watch natural convection at work by taking a smoking incense or punk stick and watching how the air moves. Toilet paper strips work well too. Supplementing natural convection helps improve the fan's efficiency. There are times where putting the fan low will not work well at all. Consider this scenario with a basement stove: A fan placed low, at the bottom of the stairs blowing upward is not going to work well. In that case the fan would be blowing against the cool air flow coming down the stairs. You can test this with toilet paper or by putting a thermometer high and low. Cool air will be naturally flowing down the stairs and warm air will be exiting the basement at the top of the doorway. But if you take the same fan and put it at the top of the stairs on the floor pointing downstairs then it is assisting the natural convective flow. Much more warm air will be exiting from the top of the doorway.

That said both ways can work. One could put a fan at the top of the basement doorway blowing into the main floor. One is just more efficient than the other because cold air is denser. I have an ideal case with the upstairs master bedroom where I tested both ways with the fan high and low. The heat pours up the hallway, but doesn't flood into the MBR too fast due to the doorway. In that test, putting the fan low achieved a faster temperature change of about 5 degrees in the room after 30 minutes. The fan set high at the top of the doorway took almost an hour to get the same results. These are things that heating geeks do on long winter nights. :rolleyes:
 
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This has been a very informative thread for me. This year when I start burning, I am going to use some incense sticks per above and actually watch my air movement in the house, and adjust my strategy for air movement accordingly.
 
I have a cape with a center chimney and I am able to push cool air into the stove room in a horse-show pattern blowing the cold air towards the stove with a box fan. from the coolest part of the house. This works surprisingly well. When we turn the box fan off, the temperature of the coldest room can drop 10-15 degrees.

We also installed one of these

http://www.tjernlund.com/airshare_ventilation.htm

which is setup next to the stove to push some of the hottest air directly into some of the coldest. this surprisingly does not do much.
 
This has been a very informative thread for me. This year when I start burning, I am going to use some incense sticks per above and actually watch my air movement in the house, and adjust my strategy for air movement accordingly.
That's the best strategy. There can be a lot of differences in house floor plans. Ranches are pretty easy to guess at because they so often have a T layout with bedrooms and a hallway. Other houses and floorplans can be more challenging.
 
Okay with all this new technology, lol, when running your stove do you have ceiling fans on reverse to pull the cold air up or push the hot air down?
 
I don't have a ceiling fan, but in addition to having a box fan move cold air into the stove room, I have a small fan on the hearth to the side of the stove that blows cold floor air towards the back of the fireplace. This pulls heat off the stove and masonry, as well as giving the natural convection flow a little boost. Works great for me.
 
After you get all those strips of toilet paper hanging from the ceiling and doorways, leave them up there! You'll be the talk of the neighborhood...local TV station may even come by for an interview.
 
After you get all those strips of toilet paper hanging from the ceiling and doorways, leave them up there! You'll be the talk of the neighborhood...local TV station may even come by for an interview.

used, or unused, strips?
 
Great thread, thanks all. I'm contemplating how to get heat from my stove on the main floor down to my basement. I think the longer-term solution might be some fans and ducting and a stove specifically made for this (see this thread)...but this thread got me thinking a lot more about air flow, and the suggestion to play with cheap fans first.

I'm all ears if anybody has any suggestions on my situation...forcing warm air downstairs. Maybe 2 fan-powered ducts? The first blowing warm air from the ceiling above the stove to the floor of the basement, and the second blowing cold air from the floor of the basement to the floor near the stove? Or maybe the basement inlet/outlet need to be further spaced (e.g., warm air in to ceiling, cold air out from floor)?

Any experiences would be great to hear.

Thanks.

-Rob
 
Methinks the odds are that is not going to work well.
 
I have to admit having a fan on the floor blowing the cold air into the room with my stove does really work and circulates the warm air much more than I would ever thought. This also keeps the room with the stove cooler and the rest of the house much warmer. And all I did was to buy a little $15 Lasko fan which is a small investment for such a great improvement. Great idea guys and thank you!

Fan.jpg
 
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Okay with all this new technology, lol, when running your stove do you have ceiling fans on reverse to pull the cold air up or push the hot air down?
Run them blowing up, works better if the fan has a down rod to space it away from the ceiling. We get much more heat from our stove in the far corners and rooms this way.
 
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I did the toilet paper test, hanging strips from the top's of all the doorways in my house really does show how the air is circulating. What a big difference with the fans off and on. I'm not sure where my electric bill will be but there is great air circulation in my house.

A list of the fans when all on:
Eco Fan on stove
Small fan on floor at side of stove
Ceiling fan
Small fan on floor outside blowing into room with stove
Fan in oil furnace with humidifier
 
I have to admit having a fan on the floor blowing the cold air into the room with my stove does really work and circulates the warm air much more than I would ever thought. This also keeps the room with the stove cooler and the rest of the house much warmer. And all I did was to buy a little $15 Lasko fan which is a small investment for such a great improvement. Great idea guys and thank you!

View attachment 165698
There are also other variables such as lifestyle. Our ranch is basically two large rectangles separated by one door, common area/bedrooms on either side of door. We spend all our time in the common area until its time for bed. In the time from say, 7pm to 9:30, there's not enough time to heat 3 bedrooms, 2 baths (900 sq ft) at the rate of air exchange. You also have to figure in cold air being replaced in the bedrooms from outside.
 
By pushing the cold floor air back to the stove room it has a clear shot along the floor. The warm air that moves back to take its place is "overflow" air that is lower than door top level. As it flows thru each door it swirls and mixes with the air( above the door) in that room giving a more comfortable result. Its a case of moving the air where it wants to go anyway.....more efficient
 
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