Moving Heat With Central Air

[fhon]

Sorry if this isn't the right area for this.

I have a central air system in my home and was interested in moving the return to the basement where the stove is. Currently the return is on the second floor near the bedrooms. (The farthest area from the stove) All the registers are on the second floor with the duct-work in the attic.

My theory is that during the winter, running the fan would distribute the warm air from that room to the upstairs. And in the summer the AC would pull the cool air from the basement to cool the house and at the same time help to dehumidify the basement.

Sounds good in theory but how well would this really work? Also does anyone know the "legality" of the return near the stove as far as the insurance company is concerned? And finally, how much would this affect the negative pressure in that room? I do have a decent downdraft but it's no issue once it gets going. The whole basement is pretty much open and right beside the stove is a large opening into the second floor where the stairs go up. So I'm thinking getting air back into the basement should be too much of an issue.

Any thoughts or input would be greatly appreciated.

 

[begreen]

Code states the return should be at least 10 ft away from the stove. Generally HVAC systems don't the best job due to heat loss in the ductwork. I'm surprised there is no return on the first floor. That is unusual.

 

[bobdog2o02]

Code states the return should be at least 10 ft away from the stove. Generally HVAC systems don't the best job due to heat loss in the ductwork. I'm surprised there is no return on the first floor. That is unusual.

I know some NFPA jargon being an alarm tech, is that a should or a shall, and what code and edition. My current setup conforms to the should but not the shall.

 

[fhon]

Thanks for the reply. I get that. I'm sure I'm losing a lot of cool air up in the hot attic right now. But the second floor is never the temperature I want, unlike the basement which is cold in the summer and hot in the winter. It's gotta be better than that right?

 

[JA600L]

I've played with this idea some. I have a very similar setup. The results I got were a lot more even heat distribution but slowly falling temperatures. I plan on adding 10'' of attic insulation this winter along with air sealing, and covering the ducts with insulation/batts. Then I will retry. A programmable thermostat would be nice too. You could make the fan come on so many times a day. I like this idea as you would also be filtering the air in the house.

 

[BrotherBart]

But the second floor is never the temperature I want, unlike the basement which is cold in the summer and hot in the winter. It's gotta be better than that right?

The reason I quit running the 36,000 BTU, 3 ton, central air unit years ago and put a 6,000 BTU window unit upstairs and a 5,000 one downstairs and keep the place cooler. The one downstairs hardly ever gets used. Duct losses in the attic were eating my cooling dollars and I had to freeze my butt off downstairs to keep the upstairs cool.

Not anymore. And the electric bill in summer dropped like a rock.

 

[fhon]

The reason I quit running the 36,000 BTU, 3 ton, central air unit years ago and put a 6,000 BTU window unit upstairs and a 5,000 one downstairs and keep the place cooler. The one downstairs hardly ever gets used. Duct losses in the attic were eating my cooling dollars and I had to freeze my butt off downstairs to keep the upstairs cool.

Not anymore. And the electric bill in summer dropped like a rock.

Haha, unfortunately I don't have a single window in this house that would fit an AC unit.

 

[fhon]

I've played with this idea some. I have a very similar setup. The results I got were a lot more even heat distribution but slowly falling temperatures. I plan on adding 10'' of attic insulation this winter along with air sealing, and covering the ducts with insulation/batts. Then I will retry. A programmable thermostat would be nice too. You could make the fan come on so many times a day. I like this idea as you would also be filtering the air in the house.

Alright, so it sounds like it works well, but I should really insulate the duct work. Thanks a lot

 

[BrotherBart]

A mini-split or two would handle that problem nicely. And give cheap heat in the shoulder seasons.

 

[fossil]

I know some NFPA jargon being an alarm tech, is that a should or a shall, and what code and edition. My current setup conforms to the should but not the shall.

NFPA publications are not codes. They are recommendations from a non-governmental industry group. Many local jurisdictions have adopted NFPA wording when writing their codes, which then become enforceable requirements. Many have not. The local Authority Having Jurisdiction is the source of requirements in any specific location.

In any case, what begreen is referring to is not NFPA, but the most typical requirement to be found in Mechanical Codes nationwide...which are a part of building codes, and thus, in your words, "shalls", rather than "shoulds". Rick

 

[Nick Mystic]

I have two stoves: one in the basement and one upstairs in the living room. When we first moved here the previous owner told me he heated the entire house by just burning the basement stove and running the central heating system's fan to distribute the heat. There are two large cold air returns: one is near the basement stove and the other is in the living room. I tried using the furnace fan to suck heat from the basement stove (I closed off the living room cold air return leaving only the basement one open), but I couldn't get any meaningful heat to move upstairs through the registers. In my case, I think the main problem was that my basement walls are uninsulated and I could never get enough heat downstairs since I didn't run that stove 24/7. If you can get your basement hot enough maybe you'll have better success.

 

[Laurent Cyr]

In my case, been there, done that. I have central air heating in my home. The home is a typical bungalow, and not 2 stories high like yours. I have a cold air return in the basement, where my stove is located. When I run the fan on the central air heating unit, it does raise the temperature, but it is still minimal. The temperature downstairs remains considerably higher than on the main floor. Instead, I turn the central air heating fan off and installed a floor fan pushing cold air on the floor towards the wood stove. I also cut a hole in the floor and put in a floor register. The floor fan creates air flow, and the cold air from the first floor flows naturally down the basement stariway to the wood stove, and the hot air flows naturally up that stairway to the first floor. To date, it is the best way I`ve been able to heat the main floor. I agree with the others that there is heat loss in the duct works, even if you decide to insulate them. My basement if fully insulated, so there is no heat loss from the walls.

 

[gzecc]

Sorry if this isn't the right area for this.

I have a central air system in my home and was interested in moving the return to the basement where the stove is. Currently the return is on the second floor near the bedrooms. (The farthest area from the stove) All the registers are on the second floor with the duct-work in the attic.

My theory is that during the winter, running the fan would distribute the warm air from that room to the upstairs. And in the summer the AC would pull the cool air from the basement to cool the house and at the same time help to dehumidify the basement.

Sounds good in theory but how well would this really work? Also does anyone know the "legality" of the return near the stove as far as the insurance company is concerned? And finally, how much would this affect the negative pressure in that room? I do have a decent downdraft but it's no issue once it gets going. The whole basement is pretty much open and right beside the stove is a large opening into the second floor where the stairs go up. So I'm thinking getting air back into the basement should be too much of an issue.

Any thoughts or input would be greatly appreciated.

Be sure your not making your basement into a negitive pressure environment and pulling CO (from your furnace in your basement) into your return. It would suck to wake up dead one day!

 

[Bigg_Redd]

Sorry if this isn't the right area for this.

I have a central air system in my home and was interested in moving the return to the basement where the stove is. Currently the return is on the second floor near the bedrooms. (The farthest area from the stove) All the registers are on the second floor with the duct-work in the attic.

My theory is that during the winter, running the fan would distribute the warm air from that room to the upstairs. And in the summer the AC would pull the cool air from the basement to cool the house and at the same time help to dehumidify the basement.

Sounds good in theory but how well would this really work? Also does anyone know the "legality" of the return near the stove as far as the insurance company is concerned? And finally, how much would this affect the negative pressure in that room? I do have a decent downdraft but it's no issue once it gets going. The whole basement is pretty much open and right beside the stove is a large opening into the second floor where the stairs go up. So I'm thinking getting air back into the basement should be too much of an issue.

Any thoughts or input would be greatly appreciated.

You'd be the first guy in the history of forever if you make it work.

 

[Andy S.]

My theory is to block my return in the stove room (my family room) and block the registers in my MBR (which has a return). The thought is that the air will be forced into the heated room and will drive the heated air out and the return air upstairs will draw the heated air upstairs and through other rooms along the way. Adapting it to the OP's set up,I'd do the opposite - have return air away from the basement stove and cut a vent into the basement.

The ductwork is now not being used to move heat but only return air. Anyone try this yet?