Moving air

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tinman1

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Oct 28, 2014
123
Long Island New York
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I'm Trying to move the air from the stove room ( insert) to the bedroom which is directly behind but 22' away. I installed a doorway fan and that is not working. The stove room temp is 77 degrees , the bedroom is at 73 degrees ( only because wifey had the base board run until it hit 72 degrees) , but the area over the bedroom door (transom ) measures 76 degrees. My question is if I install a wall grille at the transom do you think that 76 degree air would travel thru to the bedroom with natural convection ? Not using that fan ? I attached pictures to view . ( yes the stove room is cathedral at 15'-6" )
 
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If there is a ceiling fan in the stove room, turn it on, in reverse so that it's blowing upward. Then put a table or box fan in the bedroom, placed on the floor near the doorway, pointing toward the woodstove. Run it on low speed. It will blow the cooler air down low, toward the woodstove. The denser cool air will be replaced with lighter warm air from the stove room. Running this way you should notice at least a 5F increase in the hallway temp after about 30 minutes running.
 
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If there is a ceiling fan in the stove room, turn it on, in reverse so that it's blowing upward. Then put a table or box fan in the bedroom, placed on the floor near the doorway, pointing toward the woodstove. Run it on low speed. It will blow the cooler air down low, toward the woodstove. The denser cool air will be replaced with lighter warm air from the stove room. Running this way you should notice at least a 5F increase in the hallway temp after about 30 minutes running.
Did that once before with a small floor fan in the bedroom & did not work.I do believe the ceiling does help move the air around , but trying to get this warm air into the bedroom is a challenge !
 
I would get that little fan or something similar down on the floor. Up that high you are moving the warmest/lightest air in the room against colder/heavier air. This is a self defeating process. Get it low and put it on low and leave it there all the time. Eventually you will get a convection flow that is pulling warm air into the bedroom. That and get a mattress pad that plugs in and has the dual side heat option. You wont like it on high - but it sounds like your wife would.
 
I have a threshold at the door to the bedrooms, I reckon you do too. I think the warm, lighter air takes the easier path around the threshold, staying in the stove room.
 
Yup what jeff_t said. Then do some experiments with the fans. One up one down etc, especially if you have a bigger house. It took me 15 different configurations before I got the most efficient way of moving the hot air from my downstairs. If your insert room has cathedsral ceiling all of the hot air is stuck up their, get yourself a 40 dollar laser thermometer so you can take temps and see where you air is staying. Sometimes ceiling fans arent the best as they spread air around instead of focusing the air like a box fan will. I took a nicer looking box fan and put it on my ceiling and pointed it down and toward my bedrooms and that made the biggest improvement.
 
Based on my experience I would say you should expect a four degree drop off in the rear bedroom no matter what you do to move the heat. Think about it for a minute: In the stove room you are getting all that radiant heat coming off the stove to warm the walls, floor, ceiling, furniture, etc. Those objects in turn heat the air in the room giving you the elevated temperature in there. Now, even with a maxed out convection current (assuming you could establish one) all you can do is move some warm air down the cooler hallway 22 feet causing it to lose heat all along the way. By the time it arrives at the bedroom it has to be cooler than in the stove room. Once the warmer air enters the bedroom it will start to heat it and the objects in it, but it can't possibly heat them as much as in the stove room since the air temperature has already dropped off. In our house the master bedroom is right next to the living room where our big stove is located. I have a paddle fan directly over the stove blowing down from the cathedral ceiling and establish an excellent convection current into the bedroom. However, we consistently register several degrees cooler in the bedroom.
 
My house is 3000 square feet my stove is down stairs in the living room, the heat is roughly 80 degrees downstairs and my upstairs on one side is 74 and on the other side 70. The 70 degree side is above the garage. These are temp taken when it is 20 degrees outside. This is also with the stove being at 60 percent heati capacity roughly. Overall I am 100 percent happy with my temperatures as I am using my blaze king ultra to heat my whole house no oil at all! Next year I will redo my insulation in the garage and I will be good. I only fill the stove once every 24 hrs.

You need to experiment with your fans. My results of experimentation have shown a positive of 5 degrees.

Get a temperature gauge so you can monitor your hot spots
 
I have a threshold at the door to the bedrooms, I reckon you do too. I think the warm, lighter air takes the easier path around the threshold, staying in the stove room.[/q]
HHav
I have a threshold at the door to the bedrooms, I reckon you do too. I think the warm, lighter air takes the easier path around the threshold, staying in the stove room.
Have you found away to move the warm air into the bedroom ?
 
My house is 3000 square feet my stove is down stairs in the living room, the heat is roughly 80 degrees downstairs and my upstairs on one side is 74 and on the other side 70. The 70 degree side is above the garage. These are temp taken when it is 20 degrees outside. This is also with the stove being at 60 percent heati capacity roughly. Overall I am 100 percent happy with my temperatures as I am using my blaze king ultra to heat my whole house no oil at all! Next year I will redo my insulation in the garage and I will be good. I only fill the stove once every 24 hrs.

You need to experiment with your fans. My results of experimentation have shown a positive of 5 degrees.

Get a temperature gauge so you can monitor your hot spots
Yes my main hot spot is at the threshold above the master bedroom door ! If I can only get that air to pass thru the door opening ,that room would definetly rise in temperature.
 
Is your stove your soul source of heat, or do you have a central furnace as well? If so, you could try turning on your furnace fan only, it will circulate air through the entire place(stating the obvious, but it took me a while to think to do it in my house!)-
 
That might work in a modern system, but only if it is fully insulated. HVAC furnace ducting are designed for much higher duct temps unless it's a heat pump system. If the ductwork is not sealed and well insulated the furnace system will often lose more heat to duct loss. The net result can be a loss rather than a gain.
 
Where would the heat be lost to? If none of the ductwork is outside the house, how would you lose heat? Just trying to make sense of it myself, not questioning your knowlage-
 
We have the oddest shape home! An L shaped ranch with a circle at the top of the L with 4 rooms. The stove is located in the bottom of the L facing the opposite of the rest of the house. The bedroom directly behind the stove was always coldest. We put in a duct in the attic with a small fan, from the stove room to the hall, just outside that cold room. Now it's quite warm there. Not too spendy either.

edit: thickly insulated duct in the attic, not just duct
 
Where would the heat be lost to? If none of the ductwork is outside the house, how would you lose heat? Just trying to make sense of it myself, not questioning your knowlage-
Typically the heat is lost to a cold basement or attic.
 
Have you found away to move the warm air into the bedroom ?
I have experimented with fans, but the most I've seen is a few degrees higher over a 3/4 hour period. Plus, having fans in a hallway isn't feasible. I did contemplate cutting holes in the bedroom closet floors and installing a two-way air movement ductiing system with the stove room. Rather than doing that we decided to go the minisplit route.
 
Interesting.The upstairs hallway is nice and toasty due to convection up the open staircase, but it doesn't get into the master bedroom all that well. I got a 5-6 deg rise in about 30 minutes in a colder bedroom with a fan on the bedroom floor blowing out into the hall. That impressed me because it was through a 3ft doorway.
 
Our stove is installed centrally in our ranch. The kids bedrooms are on one side of the house the master on the other. For heat, through natural convection, to make it to the kids rooms, it has to make it past three door ways and down a hall. There was no good combination of fans and positions to get the heat back there. The temperature difference was 20F between the girls room (farthest away) and the living room.

We installed a Panasonic FV-30NLF1 340 cfm inline fan in the attic. The return air (to the fan) comes from two grills (Panasonic accessory) installed on opposite corners in the living room ceiling, through R-8 flexible ducting to the fan which is internally insulated. The supply air then travels through R-8 Flexible ducting to registers installed in the bedrooms. All the ducting was buried in the cellulose insulation already in the attic.

The results are spectacular. The whole house (due to the location of the bedrooms of course) is now within 2 F of the Living room. This approach has worked very well for us and the fan is nearly silent. You can only notice it if you have nothing on and you focus on it. I almost went with the 440 cfm model, less dwell time in the ducting equals less heat loss for that mass of air, for the three vents we installed the 340 cfm model is perfect.
 
Our stove is installed centrally in our ranch. The kids bedrooms are on one side of the house the master on the other. For heat, through natural convection, to make it to the kids rooms, it has to make it past three door ways and down a hall. There was no good combination of fans and positions to get the heat back there. The temperature difference was 20F between the girls room (farthest away) and the living room.

We installed a Panasonic FV-30NLF1 340 cfm inline fan in the attic. The return air (to the fan) comes from two grills (Panasonic accessory) installed on opposite corners in the living room ceiling, through R-8 flexible ducting to the fan which is internally insulated. The supply air then travels through R-8 Flexible ducting to registers installed in the bedrooms. All the ducting was buried in the cellulose insulation already in the attic.

The results are spectacular. The whole house (due to the location of the bedrooms of course) is now within 2 F of the Living room. This approach has worked very well for us and the fan is nearly silent. You can only notice it if you have nothing on and you focus on it. I almost went with the 440 cfm model, less dwell time in the ducting equals less heat loss for that mass of air, for the three vents we installed the 340 cfm model is perfect.
Thank you for this post
I was going to do something different but similar ,
How does the fan turn on ? Thermostat? Or you have a manual switch ?
 
How does the fan turn on ? Thermostat? Or you have a manual switch ?
The fan is rated for continuous operation. I have wired it to a switch on the wall of the living room. Initially I was going to install a Line voltage Cool Only thermostat, but decided that manual control is acceptable since it will likely be on all the time during the heating season anyway.

I also need to mention that our HVAC runs are in the Crawl space, so floor registers. This setup only works well when the HVAC is NOT running. I have two teenagers and bedroom doors are closed most times. The air pumped into the rooms from the ceiling is the hot air from the living room, cold air returns through the existing HVAC bedroom floor registers to the Living room floor registers. Each bedroom has a ceiling fan running, in reverse, to stop stratification. We do NOT run the ceiling fan in the living room, this is where we WANT stratification.
Thus far into the heating season, short but cold, we have been able to easily keep the house above 72F with the stove only, so running the HVAC is a non-issue.
 
I once installed a wood stove in the basement of a big ranch home in upstate New York. The stove was located at bottom of the stairway leading up into the kitchen-dining room area, so I assumed the heat would easily make its way up the open stairway. The basement was very warm and the rest of the house stayed quite cool. After some experimentation I decided to install floor resisters in the two cool bedrooms at the far end of the house away from the stove. This provided no change. Then it hit me, I installed 8" round ducts from the floor registers in the bedrooms down to within a foot from the basement floor. This caused an immediate improvement in temperature regulation. If I tried to hold a lighted match under the "cold air" duct the falling air would extinguish the flame. The home became much more equal in temperature and the owners were pleased with the passive air movement. You've got to get the cold air back to the warm area if you want the warm air to move.
 
I once installed a wood stove in the basement of a big ranch home in upstate New York. The stove was located at bottom of the stairway leading up into the kitchen-dining room area, so I assumed the heat would easily make its way up the open stairway. The basement was very warm and the rest of the house stayed quite cool. After some experimentation I decided to install floor resisters in the two cool bedrooms at the far end of the house away from the stove. This provided no change. Then it hit me, I installed 8" round ducts from the floor registers in the bedrooms down to within a foot from the basement floor. This caused an immediate improvement in temperature regulation. If I tried to hold a lighted match under the "cold air" duct the falling air would extinguish the flame. The home became much more equal in temperature and the owners were pleased with the passive air movement. You've got to get the cold air back to the warm area if you want the warm air to move.
Thank you for the reply. I have one small fan on the bedroom floor blowing the cold air out of the room,& yes it raised it up about 2degrees ! Again the insert is 22' away from the bedroom , maybe I will add a 2 small fan at the 1/2 way point so it's like a relay ?
 
I didn't see an answer to the t.p. test suggested by Jeff. Did you try it? If a fan is blowing from the bedroom to towards the stove room that air will have to be replaced by warmer air up top. I'd put one fan on low blowing out of the bedroom and another fan on low blowing into the stove room. After that it is just a matter of time. The t.p. test will show the movement of the air. My own problem is that my insert is simply too small to yield the results I want.
 
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