Circulation advice

[Matt1538]

Greetings,
This is our first winter in a new home. Our house is heated by oil but we have a wood burning stove. We have tons of wood after getting ten trees cut down and have burning quite regularly. The downstairs gets plenty warm but I can't seem to get air to flow upstairs very well. The stove had a blower and I have a couple decent air circulating fans. Any advice how to circulate more of that heat upstairs? Should I blow hot air directly upstairs, blow the cold air a somewhere and pull the warm air, etc? I know without a layout of the house this might be a difficult question but any input would be welcome.

 

[KindredSpiritzz]

I'd keep trying different things til you find something that works. Is it possible to cut some vents in the floor to let the heat rise thru to the 2nd floor?

 

[begreen]

@Matt1538 can you draw up a quick sketch of the 1st and 2nd floorplans and post it? Include door openings with rough size, stairwell, and stove locations.

Also, are there any confounding factors like high ceilings? Ceiling fans in any rooms?

 

[Shmudda]

Who in the world would cut holes or vents in your floor? Such hacks!

Since you have an oil furnace then you have forced air heat, which should include some cold air return ductwork. See if you can cut some vents into the basement cold air return ducts and place louvered vents in them. This way the furnace blower will pull some of the heated air hanging out at the first floor floor joist elevation (basement ceiling) and circulate it thru the home. I did that with mine and it made a world of difference

Craig

 

[illini81]

In order to get the stove to heat areas of the house far from the stove, you need to encourage a convective loop (hot air away from the stove and towards the far reaches of the house, cold air back to the stove). The best way(s) to encourage the convective loop are really going to depend on your specific situation. I’m new to this, but here are a few rules of thumb that I found on hearth.com while reading similar threads:

1. It is easier to move cold air than warm air, since it is denser. With this in mind, envision the path through your house that you want the air to take, pick one spot in the convective loop and add a fan on the floor (in the path of the cold air returning to the stove) pointing towards the stove.

2. There is going to be a relatively natural way that the air is going to want to flow. There are going to be things you can do to augment this, or slightly redirect it, but not to drastically change it (e.g. you probably can’t use a stove on your main level to heat the basement, because that would require hot air to fall when it wants to rise)

3. In general, the air in a convective loop is going to move slowly. There probably isn’t a need for more than one or two fans running on low. My set up requires one fan at a specific choke point. I experimented with different fan speeds and found no difference in temperatures throughout the house. The difference in temperatures with the fan off/on is night and day though.

 

[becasunshine]

Move the cold air. Per above, it is dense and easier to move.

Leave the heated air to its own devices. It will move itself. Besides, trying to move heated air with a fan will only cool it down- which is not what you want.

We have a one story ranch with a largely open floor plan at one end, in which the wood stove is located, albeit the wood stove is darned near at the center point of the house, and also at that terminus of the typical ranch hallway leading to the bedrooms and bathrooms.

We move air in this house by putting a simple, ~$20 (or less expensive) box fan on the floor at the midway point of the hallway. The fan is in front of the door openings from bedrooms/bathrooms into the hallway, so it is pulling cold air out of all of these rooms. The fan's exhaust is blowing toward the terminus of the hallway at which the wood stove and the rest of the house are located, i.e. we are moving the lower lying cold air near the floor in that half of the house toward the wood stove and the open concept area of the house.

Even though the fan is blowing out of the hallway and toward the wood stove, one can actually see the steam from the stove top steamer moving sideways and backwards toward the hallway, which is just to the side of the stove.

One might think that the fan would push the steam away from the hallway and toward the other end of the house, but nope- the steam is drawn with the warm air, which is following the convection current.

The fan pulls the cold, dense air near the floor from the bedrooms and bathrooms into the room that contains the stove. As that air moves out of the bedroom and bathroom spaces, the warm air near the ceiling in the open concept area of the house moves back toward the bedrooms and bathrooms to fill that void.

The steam gives visual confirmation of the air's movement and the convection currents.

The bedrooms and bathrooms stay comfortably warm.

Stairs and a second story complicate your scenario, but I've read accounts of people who put pedestal fans at the bottom of staircases, pointed up the stairs, which has rendered similar results.

 

[illini81]

The steam gives visual confirmation of the air's movement and the convection currents.

That's pretty cool that you have a visual!

 

[illini81]

Another thing to add… Do you have any headers that prevent the convective loop from setting up? Before getting my stove, I had read that a header can restrict up to 70% of the airflow through a passage. I found that hard to believe, but I have absolutely found this to be the case in my situation. In my house, there is a sunroom with a wide doorway (5 ft wide maybe) that is maybe 10 ft from the stove. However, this room is usually several degrees cooler than our upstairs hallway, and usually similar in temperature to our upstairs bedrooms. To get upstairs, the warm air has to travel about 10 ft forward of the stove, make a right turn, go through a doorway, travel another 10 feet to the stairs, and make a left turn to go up the stairs. The reason a space so much further from the stove is warmer than a space very close to the stove is that a header blocks the air from flowing easily into the sunroom. A header also blocks the air from traveling upstairs, but a box fan at the floor under this header takes care of that choke point. Once the air gets past this choke point, it can travel one of three places: 1. Into the office on the left hand side, 2. Into the playroom on the right hand side, or 3. up the stairs. Options 1 and 2 are restricted by additional headers, and so the air takes the path of least resistance up the stairs.

We hadn’t really thought air circulation through very much before buying our stove, other than wrongly assuming we wouldn’t be able to heat the whole house and planning on taking down some walls in the future with that goal in mind. But as long as we have the box fan running at the one key choke point, everything works out pretty nicely. The room we use most (combined kitchen, dining room, living room) stays nice and warm (70-74), the bedrooms are cooler (65-70), and the other rooms that we use less are usually close to the temperature of the bedrooms, despite being much closer to the stove.

 

[becasunshine]

That's pretty cool that you have a visual!

You can achieve the same visual with a roll of toilet paper and some Scotch tape. Tape a strips of toilet paper to the upper edges of the door frames in your house, with the strip hanging down in the center of the open doorway. The toilet paper will waft in the direction of your convection currents. You'll see if the air is circulating on its own, and in which direction. This can help you in assisting the airflow, as opposed to working against it.

The toilet paper, hanging in the upper half of the door frame, will show you the direction in which the warm air is moving through the upper portion of your home. Remember, the cold air is below, on the bottom half, moving in the opposite direction. You want to use fans to move the cold air- so if you use fans to assist, have them blowing the cold air in the opposite direction that the toilet paper wafts.

 

[edyit]

I did this once, my wife looked at me like I was absolutely insane. The kid thought it was cool though when I explained to him how convective loops work. The fan was blowing one direction on the floor and the paper was blowing in the opposite direction on the ceiling.