I guess I figured out fan placement for my house

[area_man]

In my last house, the MBR and one of my kids' bedrooms were very hot while the downstairs was cold. I tried all kinds of things to figure out where to put fans so that heat was distributed more evenly throughout. Eventually I found that putting a fan that tilted from horizontal to vertical put at the base of the stairs and set to blow about 45 degrees up the staircase was the best. I don't know why this was the solution, but I guess it's easier to blow cold air up to mix with the hot air at the apex of the house than it is to blow the hot air down.

In this house the wood stove is downstairs, so is my bedroom, and the kids' bedrooms are upstairs. I tried to use the same principle of blowing cold air to the hottest part of the house and it seems to have evened things out fairly well. I put a box fan at the top of the stairs that blows the coldest air upstairs down to where the wood stove is located. When I sit still anywhere upstairs I seem to feel a little air movement at my feet. At the base of the staircase downstairs I can feel the movement of cool air at my feet, and I can feel warm air drafting up when I put my hand close to the ceiling.

The circulator fan only tilts horizontal to vertical so I can't set it to blow down the stairway, my only option is to blow straight into the staircase. There is no extra space in this house to mount a fan on the wall or on one part of the staircase so I'm doing what I can with what I have.

The only thermometer I have is a DaVinci style that takes some time to get a reading, but my best guess is that downstairs is 74 and upstairs is close to 72. The last time I called the electric company to see how much it costs to drive a box fan is $.05/hr, so about $1.20 a day. It only makes sense to run the fan when the wood stove is burning, so I will probably run it half time

 

[DanCorcoran]

Your best bet is a box fan on the floor, at the top of the stairs, blowing cold air down. There are many threads on this site which will confirm this. Perhaps you can rig a way for your fan to blow down, or get a $10 box fan at WalMart. Use the search box at the top and you'll be able to read lots of discussions on the topic.

 

[Mr A]

It seems that air movement is counter intuitive. Moving cold air towards warm air works better than the opposite. I don't know why, it just does. Maybe a ceiling fan a tthe top of stairs would be efficient? i'm just guessing, but the heat rising up and a ceiling fan spinning clockwise would push air up to the upstairs ceiling and force it to travel down the sides of the walls, warming the upstairs section. Another fan at the top of stairs, on the floor would move cold air downstairs to be heated, and then returned upstairs and so on. Works the same in my single story house. I have a ceiling fan in the middle of the house, a box fan pointed at the fire pushes warm air up against the wall which rolls over the ceiling into the next room. The ceiling fan pulls cold air up from the floor, and pushes the warm air down. another box fan on the floor of the hallway pushes cold air into the dining room, where again the ceiling fan pulls it up and pushes warm air down along the walls that spills into the hall. I would think you have an advantage as warm air rises- upstairs.

 

[Pallet Pete]

In my last house, the MBR and one of my kids' bedrooms were very hot while the downstairs was cold. I tried all kinds of things to figure out where to put fans so that heat was distributed more evenly throughout. Eventually I found that putting a fan that tilted from horizontal to vertical put at the base of the stairs and set to blow about 45 degrees up the staircase was the best. I don't know why this was the solution, but I guess it's easier to blow cold air up to mix with the hot air at the apex of the house than it is to blow the hot air down.

In this house the wood stove is downstairs, so is my bedroom, and the kids' bedrooms are upstairs. I tried to use the same principle of blowing cold air to the hottest part of the house and it seems to have evened things out fairly well. I put a box fan at the top of the stairs that blows the coldest air upstairs down to where the wood stove is located. When I sit still anywhere upstairs I seem to feel a little air movement at my feet. At the base of the staircase downstairs I can feel the movement of cool air at my feet, and I can feel warm air drafting up when I put my hand close to the ceiling.

The circulator fan only tilts horizontal to vertical so I can't set it to blow down the stairway, my only option is to blow straight into the staircase. There is no extra space in this house to mount a fan on the wall or on one part of the staircase so I'm doing what I can with what I have.

The only thermometer I have is a DaVinci style that takes some time to get a reading, but my best guess is that downstairs is 74 and upstairs is close to 72. The last time I called the electric company to see how much it costs to drive a box fan is $.05/hr, so about $1.20 a day. It only makes sense to run the fan when the wood stove is burning, so I will probably run it half time

Setting a fan to blow cold air towards the stove is the natural pattern and works very well. In the farthest cold room set it towards the stove room this moves cold air that is settled on the floor to the stove room and keeps the hot air moving to the far end evenly. If you have a ceiling fan it needs to be set to suck air up ! The reason is cold air naturally settles down the walls so by sucking hot air up it forces the cool air down faster which warms up the rooms very fast because now the cold air is warming up. By blowing away from the stove and blowing air down from the higher level you are interrupting the natural flow and causing the air to not move efficiently. I know it sounds absurd lol but it works well many of us hearthers have learned this lesson.

Pete

 

[DanCorcoran]

Two different things going on here. In regard to moving air from upstairs to down, cold air is denser than warm air, hence the fan moves the denser (thicker) air more efficiently than it moves the less dense (thinner) warm air. Because the cold air is naturally heavier, it falls down stairs and moves along the floor, with the lighter air moving in (on its own) to replace it. Use the box fan on the floor to push the cold air down the stairs from the top, and the warm air will move up.

In regard to a ceiling fan, in the winter you want it to "mix" the air in the room, so that the hot air isn't layered at the top and the cold at the bottom, where you're sitting, but you don't want a draft blowing on you to chill you, so you direct the flow up to the ceiling and down the walls. In the summer, you're not so worried about layering (since having cooler air at the floor level near you would be better), but you do want to be "chilled", by having the air moving across the moisture on your skin, cooling by evaporation. Same reason you might sit in front of a fan in summer, but not in winter.