Thru-Wall Fans

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PhilDeez406

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Dec 4, 2012
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I am due to have my Heatilator Eco WS22 put in next week. I have a 1900 square foot modular home with the wood stove being on one end of the house, and the bedrooms and bathrooms being on the other. I have been looking into thru wall fans to install in the walls of the bedrooms to draw warm air into them. The whole house is open except for the bedrooms, so I don't think getting the warm air to the bedroom walls will be an issue. I'm just wondering how well a fan will work, and if anybody else has used them. Below is a link to the fan I'm considering. Any input would be appreciated. Thanks

http://www.amazon.com/Thru-Wall-Room-to-Fan/dp/B000JGSMUK/ref=cm_cr_pr_product_top
 
I put fans in a wall between my attached greenhouse and the kitchen on one end of my house. In my case, it turned out to work much better and be more efficient to have two fans in the wall. I have one at the top blowing from the warm room into the cool room, and another at the bottom of the wall blowing the other direction. This worked better even though I would leave the door between the rooms open. My idea had been that one fan would blow the warm air into the room, and the air would circulate back through the open door. It did, some, but it was far more efficient with the two opposing fans. For your bedrooms here, it may not make a big difference to you.
 
We like our bedroom to be what most people would call freezing. Lol I don't think it would take much to get a little heat into them, but I want to make sure my daughters room stays nice and toasty.
 
Tjernland Aireshare... Little pricey. But we'll worth it.

I tried the corner fans and also have a Broan model #512 throught the wall fan. The Broan works great, but its loud like the corner doorway fans. The Tjernland looks good and is dead quiet. :)
 
Phil, rather than putting fans in the walls, you can save yourself lots of time and dollars and move that air really easy. The quick cure is to use a small desktop fan. You don't need a large fan and you don't want a pedestal fan. Just a small desktop fan. For modular homes it usually works great to sit that small fan in the hallway. Sit it close to the wall so it is not in the way. Now turn it on the lowest speed and aim it towards the stove room. You will be amazed at how easily this moves the warm air.

However, if you try to blow the warm air into the cooler air, you will be sadly disappointed. The trick is to move the cool air (why you want the fan on the floor) into the warmer air (cooler is denser). This will have the effect of moving the warm air out as it is being replaced with the cooler air.

The first time I heard about this I thought they were crazy. Well, because I too am a bit crazy, I had to give it a try. Wow! I could hardly believe the difference and how fast the far rooms warmed up. Give it a try!
 
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Even if you do buy a in-wall or stud cavity fan, blow the cold air out of the room, toward the stove area. It is more efficient.
 
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The formula for heat delivery is BTU/h = 1.08*CFM*DeltaT. In other words, if the stove room is 10°F warmer than the bedroom, a large 100 CFM fan (through the wall) will move 1080 BTU/h, or about 1080/3414 = 316 Watts, less than a space heater on 'low'.

Desk and pedestal fans move a lot more CFM with less power and noise, and thus work a lot better.
 
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