# Moving hot air...options



## greg273 (Aug 5, 2003)

I dont need much ductwork in my house, but I do want to channel some warm air to the bedroom via some sort of blower. The furnace room is on the other side of the wall from the bedroom. Something with a little more force than just passive thermosiphon. 
I'm contemplating using a switch, a thermostat, and one of those bathroom ventilation blowers. They seem to have just the right amperage/per volume of air moved that I need. Which is not too much.
Now, someone tell me I am crazy for wanting to move 120+ degree air with a plastic-bladed fan. I'm guessing the plastic can take the heat... Any comments, suggestions?
Alternately, I'd like to have a 24volt DC squirrel-cage fan and a duct running both to the bedroom and the bathroom, but that is an upgrade I am only weighing at this point... Anyone know where to get small amperage DC fans? CApable of pushing hot air down a 4" pipe for approx. 25ft??


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## vallyfarm (Oct 24, 2006)

Home Depot has fans that are made to fit into round ductwork. I got a 6" fan to take heat down to the cellar, and thet work great! They are booster fans for houses that the furnace blower can't quite get the air out to the far rooms. Very quiet, and also have a thermostat (sold seperatly) to go with them. From the sound of it, you could use the 4" fan and be plenty good. Mike


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## vicker (Jul 11, 2003)

Backwoods Solar has a 4-5/8 inch muffin fan in 12 0r 24 volt. They are rated at 40-90 cfm depeding on the voltage used and used and use .2-.5 amps. They are like the litte fans in a computer but bigger and very quiet.
Price $15.


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## tinknal (May 21, 2004)

If you do not have the thermostat wired with the furnace, the fan may run when the furnace is off, bringing cool air into the bathroom.


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## Explorer (Dec 2, 2003)

All kinds of fans:

http://shop2.outpost.com/search?sea...query_string=fans&cat=&submit.x=9&submit.y=10


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## kitaye (Sep 19, 2005)

We set up a passive vent at the ceiling to go between our wood stove room and our kitchen. We have a ceiling fan in the kitchen so we hoped it would be enough to circulate the air but it wasn't. 

In the end we bought a Register assist unit from Canadian Tire. It fits right over the vent and has a thermstat built in that we set. It's been going strong for over a year now and works well. I do find it a little noisy if the rest of the house is quiet but it blends in with other white noise present.


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## Ross (May 9, 2002)

You need two vents a hot supply and a cold return, you could use insulated flex pipe and small fans as suggested but what is the furnace servicing now? Can you not tie into the existing plenums and use the furnace fan (with the supply return lines) to do the job?


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## greg273 (Aug 5, 2003)

Ross,
No plenums used in this system. I've modified a wood furnace, a Royall, by stripping off all the forced air components , and turning it into a passive, non-electric woodburner. I took the thin-gauge sheet metal off the air chamber and replaced it with 1/8" thick plate steel, but left the top piece off for now, to facilitate airflow. Eventually I want to have a metal grille covering the top of the stove... 

Airflow to the firebox is controlled by a 'custom' fabricated draft control. I've found it to work well so far. But that resulting hot air certainly needs a push to circulate well throughout the house!

My next project is plumb in a passive thermosiphon water heater.


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