Question about air movement in my situation....

[mtj53]

I’ve got a question for you guys. Over the summer I installed a new woodburning fireplace and it really puts out the heat. As expected, there is a part of the house that the heat doesn’t quite seem to reach, which leads to my question. In the photo I have attached, you can see the upstairs of my home. Currently, the door on the left is the only access to a room behind the wall that is approximately 17’ X 32’. That doesn’t allow for a lot of air movement. The part you can see around the ceiling fan is the hottest part of the house with the fireplace burning. What I am thinking of doing is towards the top of the ceiling, behind the ceiling fan towards the right, cutting out a small section of drywall on each side of the wall you can see, and installing a fan that will help move warmer air into the room you can’t see. I’ve read many posts about moving air and realize some believe it works and some don’t. I am thinking if I have the fan blow the cooler air out of the room you can’t see, into the warmer space you can see, that perhaps with the door open warm air will circulate into that room better? Or since the area where the fan will be located is so warm, would I be better pulling warm air into the room with the fan? Any idea’s or suggestions you guys can offer would be very much appreciated. I will also put links to the pictures below, each photo link also has a description of what I am after, Thank you...
http://i405.photobucket.com/albums/pp135/mtj54/upstairsphoto.jpg
http://i405.photobucket.com/albums/pp135/mtj54/upstairslayout.jpg

 

[savageactor7]

With the door open a small fan on the floor blowing the cold air out might provide some relief with the warmer air flowing back in to replace it. The thing is wood heat from a stove will NOT be even thorough the house. Over time most of us have adjusted to that. Also you could lock down any air leaks that room has around the window with caulking or maybe lay some insulation over the ceiling.

I have that exact same set up with the stove at the bottom of the stairs ...my son would keep the the door closed because it got too hot to sleep at night.

 

[Stephen in SoKY]

In combination with a small fan at floor level in a hallway returning air to the stove room, I've been very pleased with my through the wall fan I ordered from Home Depot. Here's the output side in my dining room:

And the input side during construction of the stove alcove:

It runs quietly and moves quite a bit of air.

 

[mtj53]

I definitely understand wood heat won’t be even throughout the home, just trying to control it as best I can. We had an evening last week that was 34 degree’s outside. Started the fireplace, and within minutes the main part of the house where the fireplace is located was 75 degree’s. the upstairs portion with the ceiling fan is close to 90, and at the same time, the room behind the wall stays around 65. No air leaks and plenty of insulation, if I could get some heat in there it does hold it well. I tried putting a fan in the doorway and blowing cold air out, in approximately 3 hours there was only a degree or two difference in the bedroom, however, the bathroom got very warm. What Stephen has done is very similar to what I was thinking. I even wondered if a guy could hook a thermostadt to the fan to kick on only when heat was needed.

 

[Wet1]

What is that vent in the first picture for?

Normally, I'd suggest pulling the cold air out, but if I were you, I would put a thru-wall fan to the right of that vent in the first picture and force warm air into the BR. In this case you know you have a warm spot up there so picking up warm air should not be an issue.

This is the product I'd use:
http://www.iaqsource.com/product.php?p=tjernlund_as1&product=171095&category=885

I'd place the the opening in the stairwell wall high (at the location you are thinking of putting it) to get the warmest air and have it enter the BR in the lower part of the wall cavity (maybe 6" to 12" from the floor). Since you have the door at the other end of the room, and it's located next to the stairwell, it makes for an excellent and natural cold air return (warm air is forced into the BR low and to the right of the room, the warm air rises, travels to the left as it cools, cool air exits out the door to the left and low, and then down the stairwell). You'll need to leave the BR door open for this to work though, otherwise you'd have to place a cold air return low and near the door.

That's what I'd do anyway...

 

[meathead]

What kind of fireplace did you install just out of curiosity?

 

[Stephen in SoKY]

Check out "Thermocube" thermostats. Someone here recomended them & I plan to use one this winter.

 

[mtj53]

Wet1—The vent you see in the first picture is the air return that was originally installed with the house furnace system. On a couple cold nights,with the fireplace running I tried running the furnace fan only to see if that would circulate enough air to make a difference, but it didn’t seem to help at all. The fan that you gave me the link to looks like it would work great. I hadn’t given it much thought, but it only makes good sense to bring the heat off the top of the ceiling in the one room and blow it into the bedroom down low. There is definitely plenty of heat there to draw from! Keeping the door open is no problem, I only shut it when I took the photo to show that it was a doorway in the picture.
Meathead, It’s taken up most of the summer (worth every minute!) but I just installed an Opel 2 woodburning fireplace. The dealer installed it and we just finished putting the stone up a few weeks ago. The whole project went very well, the dealer was just excellent to work with, and from what we have seen with the fireplace so far it really throws a lot of heat out. I couldn’t have done any of this without the help of everyone’s great advice here on the forum. From start to finish all my questions have been answered and then some! We actually installed the Opel 2 with the central heat option, but I would still like to install this fan for two reasons. First reason is because while the central heat option definitely works, I can already tell it will have a hard time pushing heat as far as this bedroom---especially on the really cold nights. Also, for the shoulder season the fireplace very easily heats the entire home except this one area in the upstairs. It’s entirely possible with this fan I won’t even need to use the central heat option except to pull a little warm air in the basement. That may be wishful thinking, still have alot of experimenting to do. I’ll see if I can post a photo here of the new fireplace. Thanks again everyone for the great idea’s and help…

 

[kbrown]

I like the AireShare idea, just not the price. What we are thinking of doing to heat the opposite side of our ranch home is to run 8" round insulated duct through the attic with a vent on each end which is mounted near the top of the wall just like a cold air return. Once that is done, install an in-line duct fan controlled via switch and just push the warm air from the woodstove room down to the end of house.

 

[Wet1]

Lux makes some neat thermostats that could be useful for in wall fan applications. Look at their LV1, LV2 (heating), LV3 (cooling), and their WIN100 outlet thermostat.

http://www.amazon.com/s/ref=nb_ss?url=search-alias=tools&field;-keywords=lux+thermostat&x=1&y=15

BTW, nice looking install! :coolsmile:

 

[Wet1]

I like the AireShare idea, just not the price. What we are thinking of doing to heat the opposite side of our ranch home is to run 8" round insulated duct through the attic with a vent on each end which is mounted near the top of the wall just like a cold air return. Once that is done, install an in-line duct fan controlled via switch and just push the warm air from the woodstove room down to the end of house.

You can do the same thing for less coin. Just install an in-wall fan up high (or low) and place a vent cover at the opposite end of the stud cavity. The air will be forced through the vent cover either way. This will probably kill a little of the noise from an in-wall fan as well (which would be a concern for me if I were doing this in a BR.

 

[SteveKG]

I have a situation in my house which, while not the same as yours, may apply. I have a solar-heated greenhouse, attached. I circulate air between the living quarters and the greenhouse during sunny winter days. Actually, it would get too hot in the greenhouse and the exchange cuts down on wood-stove needs.

I have a small fan blowing into the house from the greenhouse, and it is higher up on the wall. I have another fan low on the wall to return house air to the greenhouse. I just "made up" this set-up as it seemed common sense.

The result is very good. I have the fans both wired to an inexpensive thermostat and they operate on their own. I can open french doors into the greenhouse for return air, and sometimes do, but the two fans do a very nice job circulating air between the two spaces. I had reason to disconnect the lower, return-air fan for a while due to it needed motor brushes it took me quite a while to find. During that period, with the doors open for return air, the system worked but not quite as well. I did no scientific tests for this....

I imagine one large fan blowing warmer air into your large room, with the hall door open for return, may well work as well as my two small fans. I don't know. We have solar electricity so everything I do is for minimal elec. use, thus the two small fans [8"]. All I can say is the fans here do a great job of redistributing air and having the two directions blowing does help the operation.

 

[mtj53]

I appreciate the help guys and have come up with one more question for you that also may help me & others down the line. I love the idea of the Tjerlund Airshare room to room fan that Wet1 suggested. Would be great to pull warm air from up high and blow it down lower into another room. I called up and talked with the tech department and Tjerlund and the tech rep was surprised I wanted to hook up a thermostadt, he said he didn’t think it was needed because the fan was only 75 cfm. He said their fan was really meant for smaller rooms than what I was trying to accomplish. Reading the online reviews, folks that have used that setup were very happy with it, but all suggested it was meant only for smaller rooms also. With having a larger room and trying to push the warm air down, I worry it won’t be quite what I need. That leads me to my next question---is there any other room to room fans on the market that can be hardwired that move just a bit more air than the Tjerlund product? I would rather have a fan that moves too much air than not enough…any and all suggestions appreciated….

 

[Wet1]

Look at my post (#11). All you have to do is hardwire a fan of the desired size high and on the stairwell wall. Cut a hole at the bottom of that same stud cavity (located in your BR) and place a decorative grate or duct cover over the hole. The air being forced in by the fan will pressurize the cavity and be forced out that grate in your BR. I'd think an 8" fan hardwired to a thermostat with at least an 8"x10" grate in your BR would more than do the trick. I'd also watch the sound levels of the fans you're considering. Mount the fan in a layer of foam gasketing to minimize noise and vibration.

 

[Stephen in SoKY]

The one I use is either 200 (High) or 160 (Low) CFM. It should be a simple matter to hard wire it should you wish. As to noise levels, I hardly notice this one running on high in the room I spend the most time in. That said, I was very careful in mounting it to avoid any needless vibrations. For reference, here's the one I use: http://www.espenergy.com/thru_wall_fan.htm

ETA: The Thruwall Pro comes ready to hardwire. The Thruwall like I use has the plug already installed. The decibels & Sones are listed at the above web page also.

 

[mtj53]

Thanks again guys...I didn't realize you could take any fan and hardwire it. As you can see I'm not much of an electrician and I also tend to overthink things and make simple things complicated! Happy to have this site where you can straighten me out though!

 

[Russ in Chicagoland]

Watch out for a fireblock of some sort in that stud bay you're working in. Would be hard to push air through a 2x4!