Who is using their forced hot air blower to circulate?

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Oct 5, 2011
88
NH
Anyone?

I have a small 1 floor house. My bedroom on the front of the house, and the bathroom in the back of the house is usually cold. My return air duct is located in the same room as my woodstove. Would/could using the blower be worth checking out ???
 
I leave my fan on all the time. I think it helps even the heat and humidity in the house. It doesn't seem to move the heat from my basement where the stove is very well. Although I have noticed an increase in my electric bill.
 
I too leave my furnace blower on all the time. It is a 12volt DC blower that hardly uses any electric. I have found that by doing this the temperature in the house is much more consistent and there are no cold spots or drafts. Another thing I did was cut a register opening in a couple locations directly above my stove in the cold air returns This allows the furnace to pull in the heated air from the stove and distribute it around the house. This has been very effective in keeping the house warm

Craig
 
my return is located directly across the room from my insert, on the lower level. maybe 15 ft away. with the basement usually 10 degrees hotter than upstairs,(77 down 67 up on normal days) i thought it would have to move warm air around. I guess i thought wrong. I ran my furnace fan for maybe 15 minutes one day, noticed a drop in temperature by about 2 degrees upstairs, and when i was walking around, i was feeling the cool air our of the vents.
 
I leave the fan on when we are downstairs during the day, at night it gets shut off when we go upstairs. My main reason for doing this is to keep our bathroom warm, we have to shut the door so the 2 year old does not get in there and try and play in the toilet, so the fan helps circulate the warm air in there, I hate going to take a dump in a freezing cold bathroom. It also does help heat the kitchen, when the living room is 72 the vents in the kitchen are putting out 70 degree air.

My return is in the living room same as the woodstove, about 12 feet away. I have R8 ducting.
 
My air handler is in the garage and if I turn my fan on I get a quick drop in temp inside the house. I think it might be from make up air or the air handler isnt completely tight and is pulling in some cold garage air
 
Mine helps some but we don't run it much. Seems like the heat naturally finds where to go around upstairs. Our stove is in a large living room/dinning room with two walk in entries to the kitchen. Stove is upstairs so our setup is ideal. Three back rooms down a hallway run 3 to 7 degrees cooler, good for sleeping. I run the fan when the main areas get too warm like above 78 which happens easily if we aren't predicting the right heating needs correctly. Our HVAC system has two cold air returns in the basement so running the fan can drop the upstairs 5 degrees when needed.
 
Mine has a circulate setting, that runs the blower fan at low speed intermittently. Certainly doesn't warm up the far rooms as much as the stove room, but it definitely helps moderate the temps through out the house. Keeps the stove room cooler, and the far rooms warmer.
 
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It is a 12volt DC blower that hardly uses any electric.
I know they use 12 VDC in campers but never knew this about home furnaces.. Sounds like if you had a gas hot air furnace you could run it in a power outage if you had a battery backup..

Ray
 
This was suggested by a plumber/heating guy that was at our house recently. He said to trick the furnace by shutting it off, and making it just run the fan. I thought one better, and have considered hooking up a thermostat to just the fan, and locate it in the stove room. That way, you could set it to come on when it got too hot, and turn off when the fire dies down at night. The only thing I wonder about, though, is that the intake in the room is located 16' away, and on the floor, directly in front of the stove. I wonder if it would pull in enough warm air?
 
i tried it, as my return air vent is not far from the stove, but the duct is in the attic and isn't insulated too well so the air comes back out cool. i could spend the time to wrap it but then the electricity would be up and the goals are to keep the bills down.

cass
 
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i could spend the time to wrap it but then the electricity would be up and the goals are to keep the bills down.

A hot air duct in the attic should ALWAYS be insulated. How would doing this increase your electric bill? If nothing else, it'd save you money when you used your furnace, (it's electric??), or it'd work better with your wood stove.
 
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We run the central system fan a couple of time a week when the stove is really cranking just to circulate the air in the house a bit and dump some heat into the basement - duct work is down there.
 
Our stove is in our basement (finished walk out basement), and the furnace is in the next room, we opened up one of the cold air returns and run the blower during the day, it helps get heat upstairs better. We have an electronic air cleaner on the furnace as well, so it also helps remove dust and freshens the air. It gets shut off at night because it is rather noisy, and it is right next to my bedroom.
 
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Our forced air furnace has three settings that I roll through depending on different conditions. I can leave the furnace to run the fan at all times regardless of whether the furnace is heating, I can leave it on "circ" which according to the owner's manual makes the fan run 35% of the time regardless of whether the furnace is heating and I can set a specific "circ/vent" time of 20, 40 or 60 minutes where it will circulate the inside air and also introduce outside air.

So typically when the stove is running the furnace heat is off anyway and the furnace "circ" is on and between that and the cathedral ceilings with some strong ceiling fans, the temperature is pretty even. If it is incredibly cold out and I am pushing the stove to higher temps I find that turning the furnace fan full on really helps distribute the temperatures. And, if it is too warm within the house I find that putting the circ/vent on is perfect for reducing the temps a few degrees for more comfort. I have learned that doing this for the outside air offers a much more even venting than opening up one window and because all that outside air goes through the furnace filter system it is cleaner too.

It is sort of silly to think that in reality whenever the stove is on, the forced air furnace is really simply serving as a fancy fan with a fancy filter! Love It!
 
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Our forced air furnace has three settings that I roll through depending on different conditions. I can leave the furnace to run the fan at all times regardless of whether the furnace is heating, I can leave it on "circ" which according to the owner's manual makes the fan run 35% of the time regardless of whether the furnace is heating and I can set a specific "circ/vent" time of 20, 40 or 60 minutes where it will circulate the inside air and also introduce outside air.

So typically when the stove is running the furnace heat is off anyway and the furnace "circ" is on and between that and the cathedral ceilings with some strong ceiling fans, the temperature is pretty even. If it is incredibly cold out and I am pushing the stove to higher temps I find that turning the furnace fan full on really helps distribute the temperatures. And, if it is too warm within the house I find that putting the circ/vent on is perfect for reducing the temps a few degrees for more comfort. I have learned that doing this for the outside air offers a much more even venting than opening up one window and because all that outside air goes through the furnace filter system it is cleaner too.

It is sort of silly to think that in reality whenever the stove is on, the forced air furnace is really simply serving as a fancy fan with a fancy filter! Love It!
Sounds like a good setup! What would be great is if you had a thermostatically controlled fresh air louver to bring in fresh air automatically if it is too warm in your home! I wish I had installed a hot air system knowing what I know now as I could also install central air too.. If I only used fossil fuels to heat then I I like FHW heat better but the only time my furnace runs now is to maintain water jacket temps for DHW or if I am on vacation which is a rare thing in winter.. I may be going to Aruba in this winter as some friends from NH invited us to stay at their time share condo there.. Hard to pass on free lodging and some good companionship! ;)

Ray
 
Doesn't work well on most newer construction houses - a small amount of "fresh" air is brought in from outside.
We personally found this to be true when we attempted this on our previous house - the house temp gradually dropped.
Also found the just where the inlet was - must be a GFA design / code thing.
Instead, we now crack open a window in the basement & also crack open a window in our bathroom to start an air
circulation circuit - seems to work fairly well.
 
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When I want to circulate warm air from the living room stove to our back bedrooms and bathrooms, I turn up the thermostat [gasp] on our gas hot-air furnace. I only let it run one cycle, which is usually plenty. The reason I want the gas burner to fire is that when you turn on the fan in this kind of system, it draws air from the returns and passes it through a heat exchanger in the furnace. If that big chunk of iron is in a cold place (basement, garage, etc.), then it blindly does its assigned job -- exchanging heat -- only in reverse of what you want, meaning the warm stove air coming down the return duct transfers its energy to the cold exchanger and its surroundings. Oops. I've verified this with an IR thermometer.

This is why many gas hot air systems have a sensor to keep the fan from coming on until the heat exchanger is up to temp, preventing a drafty blast of cold air from coming out of the heat registers early in the cycle.

One burn cycle in the furnace doesn't use much gas and it really does distribute the stove warmth nicely. It helps that the largest return register is fairly near the stove. Next time I may try temporarily blocking the returns in the bedrooms to see if that gives me more bang for the buck.

-dan
 
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When I want to circulate warm air from the living room stove to our back bedrooms and bathrooms, I turn up the thermostat [gasp] on our gas hot-air furnace. I only let it run one cycle, which is usually plenty. The reason I want the gas burner to fire is that when you turn on the fan in this kind of system, it draws air from the returns and passes it through a heat exchanger in the furnace. If that big chunk of iron is in a cold place (basement, garage, etc.), then it blindly does its assigned job -- exchanging heat -- only in reverse of what you want, meaning the warm stove air coming down the return duct transfers its energy to the cold exchanger and its surroundings. Oops. I've verified this with an IR thermometer.

This is why many gas hot air systems have a sensor to keep the fan from coming on until the heat exchanger is up to temp, preventing a drafty blast of cold air from coming out of the heat registers early in the cycle.

One burn cycle in the furnace doesn't use much gas and it really does distribute the stove warmth nicely. It helps that the largest return register is fairly near the stove. Next time I may try temporarily blocking the returns in the bedrooms to see if that gives me more bang for the buck.

-dan
Dan oil hot air furnaces work the same way as gas.. The room T-stat says I want heat then the furnace says OK and fires the burner and a t-stat on the heat exchanger says OK I'm hot then passes this onto the circulator blower which distributes the warm air in the home.

Ray
 
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A hot air duct in the attic should ALWAYS be insulated. How would doing this increase your electric bill? If nothing else, it'd save you money when you used your furnace, (it's electric??), or it'd work better with your wood stove.

If you're going to try to recirculate stove heat through the ductwork it all should be well insulated, no matter where it's located. Otherwise the heat loss defeats the purpose.
 
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Dan oil hot air furnaces work the same way as gas.. The room T-stat says I want heat then the furnace says OK and fires the burner and a t-stat on the heat exchanger says OK I'm hot then passes this onto the circulator blower which distributes the warm air in the home.

Ray

Good point; I was narrowly focused on my own setup. And to complete the cycle, that same t-stat senses when the exchanger has cooled enough, after flame shutdown, to tell the fan to quit.

Hey, we are practically neighbors. In non-heating season I do a lot of motorcycling throughout SE Mass.

-dan
 
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Good point; I was narrowly focused on my own setup. And to complete the cycle, that same t-stat senses when the exchanger has cooled enough, after flame shutdown, to tell the fan to quit.

Hey, we are practically neighbors. In non-heating season I do a lot of motorcycling throughout SE Mass.

-dan
No kidding? Where exactly are you? I sold my Honda Shadow ACE 750 years ago due to nobody to ride with..

Ray
 
Ray, I sent you a PM, which they seem to call a "conversation" in this forum.

-dan
 
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