Warm air in or cold air out?

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olbluebird

New Member
Nov 14, 2024
8
Athens, Ohio
Hello pals,

I've been lurking this site for a super long time and finally have something to add-- I mean, ask. I have a split level house where our family room is down four-steps from the area of the house where our stove is situated. I understand I am fighting the laws of nature, trying to get warm air to the lower part of the house, but I have to try. I'm thinking of installing a ceiling fan in the lower level, accompanied by a doorway/corner type fan from the stove-level into the lower level (doorway at the top of the 4 stairs) What I'm wrestling with today is, which is more effective: Moving warmed air into the cold room or sucking air from the cold room into the stove area?
 
I doubt that a ceiling fan in the family room will make any difference. From the description it sounds like there is a wood stove on the upper level. Is that correct? If yes, what is the ceiling height in the stove room and does any portion of the stove room sit on top of the family room level?
 
I move Air from front of house to back. I tried Warm out Pushed out it worked, but pushing cold air to stove worked about 4 degrees better. Couple of Box Fans for me. You have some Nature's Laws to overcome. Warm Air Rises. Cold Sinks.
 
Best bet is to try and move cold air into the warm room. Got a drawing of your layout?
Here's a quick idea, and apologies to any real draftsmen, I hope you don't go cross-eyed looking at this. But as I attempted to demonstrate, the ceiling line is the same between the two rooms.
 

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I doubt that a ceiling fan in the family room will make any difference. From the description it sounds like there is a wood stove on the upper level. Is that correct? If yes, what is the ceiling height in the stove room and does any portion of the stove room sit on top of the family room level?
The ceiling height in the stove room is 8'. The levels are not stacked upon each other at all, you just walk down four stairs from the stove room into the family room.
 
So there is no overlap between the two levels?
 
Is there a fireplace in the family room?
 
Ok, I was trying to envision a simple ducted system but it sounds like that won't work without an offset. If the family room is well insulated then something like a heatpump or resistance heater may be more effective.
 
Guy I know has a similar layout. He used a stove for years before getting a OWB.
With his stove he built an air "return" above the stove. A small hood collected heat with the aid of a furnace fan. This was then distributed through the existing duct work. He may, or may not have, disconnected the regular furnace. Don't recall the details, for this was 20 yrs ago.

Maybe you could adopt something like this?
 
One should not be sucking air from within 10 ft of the stove.
 
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I should add, he has a cathedral ceiling. The hood was about 4' forward of the stove and 6' above.
It collected the heat hanging out near the ''peak.''
 
Guy I know has a similar layout. He used a stove for years before getting a OWB.
With his stove he built an air "return" above the stove. A small hood collected heat with the aid of a furnace fan. This was then distributed through the existing duct work. He may, or may not have, disconnected the regular furnace. Don't recall the details, for this was 20 yrs ago.

Maybe you could adopt something like this?
Interesting thought! The previous owner actually had arranged something like this; they tacked a sheet metal tray onto the side of the stove, and put cut steel pipe in the tray, so it was supposed to be a catalytic type thing?, then ran duct work from the tray under the house to floor register via a fan. I really thought it was clever, but it didn't make an appreciable difference.
 
You'd be violating code, and possibly have a functional carbon monoxide distribution system in your home.
 
Yes, better to install a small wood furnace in that case with an integrates convection jacket.
 
Getting back to the original question. You want to move cold air out at the same time setting up a convective loop that brings hot air in. Continuous low velocities are best at this. If you stir up the air with fan you loose any convective loop.
 
Getting back to the original question. You want to move cold air out at the same time setting up a convective loop that brings hot air in. Continuous low velocities are best at this. If you stir up the air with fan you loose any convective loop.
That makes sense. I've been experimenting with a box fan and so far it's much more effective to suck air from the cold room ->>stove room. My new thought would be two low rpm doorway fans, one high up one low, pulling in opposite directions. Convective loop?
 
That makes sense. I've been experimenting with a box fan and so far it's much more effective to suck air from the cold room ->>stove room. My new thought would be two low rpm doorway fans, one high up one low, pulling in opposite directions. Convective loop?
That would be my thought. I did find a box fan was too much air too fast.
 
That makes sense. I've been experimenting with a box fan and so far it's much more effective to suck air from the cold room ->>stove room. My new thought would be two low rpm doorway fans, one high up one low, pulling in opposite directions. Convective loop?

You really only need the one low blowing cold air towards the stove.
 
i think you can also use a variable speed switch, on a box fan, to slow down the speed more.
 
i think you can also use a variable speed switch, on a box fan, to slow down the speed more.
This works well. I have 2 that are in line between the plug in and the small desk top fans we use on the floor in cold portions of the house. Definitely allows a slower fan speed.
 
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Thanks everybody for your thoughtful responses. There's no doubt now that sucking air out of the cold room with a box fan works very well, now I'm looking into some of the quieter options mentioned and will move forward with that. Thanks again!