bathroom fan to move warm air from jotul F600 in basement?

[meathead]

Anyone ever try mounting a bathroom fan to move air from a stove in the basement to a room upstairs? I am thinking about mounting one between studs above my stove and venting it through a floor register to the room above like a forced hot air system. With a box built around the intake unit with another register at the bottom I think it would be easy to make it a neat looking arangement. I would wire the wall switch up in the room I want to push the air into and could turn it on/off without heading downstairs.

Only issure I can think of is the possibility that even a low cfm fan would pull too much air in and I would run out of warm air on the basement ceiling and be pulling room temp air around...still it seems I could sweep a lot of hot air upstairs with it in 4 or 5 minutes at a time then shut it down and let the stove get back to work warming the basement.

Any issues I am not thinking of? Anyone ever try this before?

 

[pen]

I have done this in my basement as it is partitioned. The main part of the basement is where the woodstove is, the other part has a seperation fire wall for a 1 car garage. I have a 50cfm bath fan hooked up that is ducted into that part of the basement. I turn this on when it is going to be down below zero to help add some more heat and also if I am going to be working out there.

At 50 cfm, don't expect miracles. but for my instance, it is a help and was no cost and uses as much electricity as a 75watt bulb. This helps me mainly because there is already a screen door inbetween the 2 basement sections. However, the warm air in the main part and cool in the other seems to air lock at that door. By pushing warm air into that part of the basement with my little fan, it seems to allow the cooler air to push through the screen door. I am always amazed at how little heat goes through that door. Perhaps the woodstove causes a draw of air from there because the garage door isn't sealed well? I dunno, however ............

Eventually, I would like to use one of these line voltage thermostats with some duct work as is shown in these links> (let me know if it won't work since I performed the search)

http://www.homedepot.com/webapp/wcs...angId;=-1&catalogId=10053&productId=100028788

http://www.homedepot.com/webapp/wcs...angId;=-1&catalogId=10053&productId=100067594

http://www.homedepot.com/webapp/wcs...angId;=-1&catalogId=10053&productId=100047556

be sure to check out the "people who bought this also looked at" section at the bottom of each page for more ideas.

pen

 

[GunSeth]

I have a half-assed version where a bathroom fan is blowing air up through a vent in the basement ceiling to help heat the upstairs. Seems to help a bit, though I still experiementing a lot with fans and such.

 

[gzecc]

Consider the possiblility of creating a negitive pressure situation in your basement and causing carbond dioxide to be pulled from any burning appliance you have in the basement. Remember, pressures change with weather conditons, flue conditions, etc. If your going to do this make sure you put redundant CO monitoring in. If you wake up dead it will ruin your day.

 

[LLigetfa]

Consider the possiblility of creating a negitive pressure situation...
If you wake up dead it will ruin your day.

I prefer to push cold air into the hearth room directly to the appliance.

 

[jwscarab]

I tried the inline fan from HD. Result = VERY NOISY.

Then I mounted a shaded pole blower in the basement and with the intake at the basement ceiling and the outtake splitting into two ducts and going out dedicated ducts on either side of the great room on the first floor. I added a thermostat set for air conditioning mode at the basement ceiling - when the basement gets to 80, it kicks on. Below 80, off. I added a fan speed dimmer switch made for that motor type to slow down the beast. Result = VERY NOISY, especially when I lower the speed of the fan.

I was told by many on here to "reverse the setup". Pull the air down the vents - pulling the cold air out of the great room, and pressurizing the basement where the wood stove is. That will force the hot air to go up the steps, and if needed, I will add 2 more floor vents for air to raise thru.

I think that all makes better sense. 1) positive pressure in the basement for better stove performance. 2) less noise due to blower air going onto basement instead of great room upstairs. I also plan on replacing my blower with a smaller cfm and running it a full speed - the way the blower was made. I also plan on replacing some of my ducting with flex to cut down on vibes. I will keep the thermostat setup - that rocks!!

 

[Stephen in SoKY]

Does anyone have first hand knowledge of the noise level of the third item shown above? I hate to cut holes only to find I can't stand the noise & I was going to order it tomorrow. Thanks>

 

[LLigetfa]

I use an 8 inch inline centrifugal blower with speed control. I mounted the blower far from the stove, in a box (sitting on concrete) that is a labrynth of different size compartments (like a muffler) and holds two furnace filters (before and after). It makes far less noise than the gas furnace blower.

 

[wccountryboy]

Does anyone have first hand knowledge of the noise level of the third item shown above? I hate to cut holes only to find I can't stand the noise & I was going to order it tomorrow. Thanks>

I have 2 of these, one going from the stoveroom to the central hallway, the other from the hallway to the MBR. They're not bad on the low setting, on high, you know they're there, but its not annoying loud. My issue with them is that they don't seem to be working for my application. I can have the stoveroom at 80* and can't get the hallway above 65*. the air coming out of the fan into the hallway seems cool, not warm. I'm wondering if its moving too much air, too fast.

 

[lexybird]

some of those cheaper ceilingbathroom fan models are really noisy and can vibrate too ,id go with the inline 6 inch inline not the ,mount it to a register assembly int othe floor and it should be quit bearable and still move penty of air the bathroom fans dont move of anything and are thrice the expense if thats your only purpose IMHO

 

[meathead]

The only issue with running the system in reverse (air forced down into the basement) is that my basment door is right by the main entry to the house in an area that is set away from the used living space. Air forced up the stairs runs directly into exterior doors and windows and a lot of heat is lost before winding its way down the hallway into the living space.

What I am now thinking I will do is button up the basement door a little tighter and run a fan of some variety down into the basement on the side of the house opposite the stove. My thought is that this would pressurize the basement and force more warmed air up through the registers in the living space, while hopefully forcing a minimum of warmed air up the basement steps and into space that really doesn't need to be heated to the level it currently is.

Those of you who know your stuff - is this pretty much the general idea? It's my first year trying to heat a house with only a basement stove - the advice is really appreciated.

Another question - does pressurizing the stove room with a fan system increase the chances of an overfire? The basement is fairly large (extends under the garage and porch putting it at over 2k sqft) and is buttoned up tight but not so tight that I would expect any such issues.

 

[branchburner]

I was told by many on here to "reverse the setup". Pull the air down the vents - pulling the cold air out of the great room, and pressurizing the basement where the wood stove is. That will force the hot air to go up the steps, and if needed, I will add 2 more floor vents for air to raise thru.

I think that all makes better sense. 1) positive pressure in the basement for better stove performance. 2) less noise due to blower air going onto basement instead of great room upstairs.

Yes... and #3, you don't want to create negative pressure so the appliance may backdraft CO. Pulling combustion air away from a stove may not be a wise move.

As for making holes in floors and walls and all that, I've done some, but not sure if I've done more harm than good. I think the points are well made that in considering any modifications to existing systems or in rigging your own HVAC system, you want to take all factors into account. The safety factor can get sidelined in our obsession with efficiency, economy, practicality, etc. The number of times I've said to myself "I don't see the harm in that" doesn't mean I'm safe - it means I think I'm safe, which can be a dangerous state of mind. My logic may be perfect, but is often based on incomplete knowledge or on faulty assumptions.

I like to use a highway analogy - do you depend solely on your mirrors or do you look over your shoulder to check the blind spot? If I never looked over my shoulder I'd have used up nine lives the first year I had my license!

 

[meathead]

Try as you may wood stoves /pellet are areas heaters. It is extrememly hard to heat a home with a wood burning appliance located in a negative pressure zone. The higher pressure above naturally gravitates to the lower zone.

Yeah...going pretty well so far - a week straight in the 20s or lower and the house held steady at 65 degrees. Worse case I'll go ahead and add another stove in the livingroom fireplace to take up the slack and put the whole place into the 70s - but for now I'd like to see what I can do with the stove in the basement as the wife likes the ambiance of the fireplace upstairs and I like a happy wife.

I'm a liscenced home improvement contractor, I follow building codes, I have redundant CO and smoke detection, and my stove is inspected and insured (actually insured for one upstairs as well just in case I want to reinstall one). I'm not going to endanger my safety or the safety of anyone in my home. If you have any advice on how to improve gains from a basement stove in upstairs living space I'd love to hear it.

 

[begreen]

If you are following code, then maintain the 10 ft distance from the stove for the fan. Also, can it be assumed that all the new penetrations between floors have been equipped with fusible-link dampers? If so, good start.

Truth be told, we all made our houses a "little" less safe by introducing a wood burning appliance into them. Same thing by adding a clothes dryer or other appliances that have a degree of risk built into them if not properly installed and maintained. Wood heating a whole house from the basement is generally inefficient, but lots of folks do it. So do it wisely and safely and let us know how it works.

 

[meathead]

No new floor penetrations yet - but replaced existing registers with fusible link damper equipped registers. As I mentioned in a previous post, the fan would be mounted on the side of the house opposite the stove, which would put it roughly 40ft from the stove.

 

[LLigetfa]

When I built my home I wanted to tie the central heat option of my RSF into the duct work for my gas furnace but was told by my furnace guy that it wasn't allowed. I didn't want to tie into the hot side, just the cold return. The furnace guy said the restriction applied only to a natural gas furnace. I could understand if the furnace used a standing pilot and the heat exchanger cracked but modern direct vent furnaces don't use a pilot and will shut down if there is an inbalance between intake and outlet.

Anyway, I had to keep the duct for the RSF completely separate from the gas furnace and it worked out fine. The hearth room is on the main floor at the far end of an ell and while it is a couple degrees warmer there, the heat does spread throughout the open concept main floor and enough heat goes up the open stairs to the second level provided doors are left open. The open central stair well is a very good conduit for convection. Maybe too good as the cool air rolls down the stairs right onto my wife laying on her sofa.

 

[begreen]

You're correct. The code is applicable to forced air furnaces. Though as noted, if the room is the sole source of return air, this is a bad idea. The risk of creating negative pressure outweighs the gains. Sounds like meathead is taking due precautions and is to be commended for that.

 

[staplebox]

OP - I tried that exact thing. Bathroom fan mounted in basement drop ceiling (?30-60 cfm can't remember / small) ducted to 11X4 in. register in floor above. Worked like crap, wasn't worth it.

I'll admit the only 'code' I know is my ATM PIN number but the stairwell opening from the basement to the floor above seems like a hell of a lot bigger "non-sealed opening" than an 11x4 in. hole in the floor.

 

[branchburner]

... the stairwell opening from the basement to the floor above seems like a hell of a lot bigger "non-sealed opening" than an 11x14 in. hole in the floor.

Yeah, but it's tough getting through the 11x14 hole to get down to the laundry room!

I always make a point of closing all doors when I'm on vacation with the thought that a fire wouldn't spread through the whole house as quickly. But when I'm sleeping upstairs, I leave the stairwell door open so I can hear the smoke detector downstairs. I'm wondering, is the answer to keep the door closed for safety and have the alarm wired to sound upstairs? Because it's true, wherever that heat flows, so does the smoke and flame.

It's easy for me to ask the question because my upstairs warms quickly, I can open or shut the door as I like. I realize many folks count on the stairwell as their main heat duct. But the point is valid - does that compromise safety? I guess we all accept that living in combustible dwellings that are heated by combustion appliances may have some inherent risk. Do you then move towards increasing risk or decreasing it?