Just installed my first woodstove, a pleasant hearth 1800sq ft woodstove in my 1200sq rancher. It’s located on one side of the house. I have floor vents and wall returns near the ceiling with insulated duct in the basement. I was wondering if it’s possible to run the hvac system fan to help circulate the warm air to the bedrooms on the other side of the house? Not sure if this is possible by running the fan only on the thermostat? There is a ceiling fan close to the woodstove so I can use that to help move the warm air around but was just curious if there’s another way. Just waiting for inspection to fire the stove up for the first time
Using hvac system to circulate woodstove heat?
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Personally, I have not had good success with using my home HVAC system fan to circulate warm air. Not sure why, but it just don’t spread the heat very well. What I’ve had excellent success with is putting a small fan in the bedroom hallway on the floor, pointed towards the wood stove room. Even on low, this causes warm air to circulate very well into the bedrooms. I’m using a small fan, it’s around 10”-12” tall in total, it’s not one of those tall fans that sits 3 feet off the ground.
Hope that helps!
I use it and I do think that it helps. But, my intake for the HVAC is near the stove room. I am hoping to pop a hole in the wall and tap into the duct work right in the stove room. That might really get it moving. The ceiling in the stove room can be 78 degrees and the thermostat on the wall in the adjacent room will only read 68 degrees. I want to move that air off that ceiling.
Beer Belly
Minister of Fire
In our Split Level Ranch, I have used the fan on the floor method with pretty good results, but what I do now, which IMO has worked better for us, is to burn oil (I know, taboo) to bring the furthest bedroom to 68*F, after that, the woodstove maintains without a problem. I will also mention, being a Split Level with the woodstove facing the stairs to the upper level bedrooms works perfect with blower on the stove pushing warm air up the stairs, so it doesn't take much to get things going.
kennyp2339
Minister of Fire
heating a ranch style house from the basement, I also have not had good luck with using the existing hvac to move heat around the house, I think since all my duct work is in the attic its just to cold so I end up creating "drafts" the best for me is to leave the far bedroom ceiling fan on low and in reverse, it seems to even out all the air in the house and create a great convective loop.
I have had minimal success so far in 2 story house. I set the thermostat to circulate runs 10 minutes every half hour or so. It gets a small amount of heat up stairs. I am going to experiment with the family room ceiling fan on reverse low and try blocking some upstairs air returns maybe even add one half way between both stoves.
Yes. Mine is at the far end of the house pointed towards the stove or door opening to the stove room. Small fan set on the floor, running on low. Gets the heat moving.
X 2. We have a 16" pedestal fan in our bedroom, aimed at the open door. Works the best for us. IMHO.
I tried this and it doesn't seem to work as well as I thought it would. Now I only have an open fireplace but it is in a large open room with 27' ceilings. The return vents are at the top of the wall by the ceiling. My fireplace gets the room to 73° (less than 30° outside). The thermostat is in the same room about 5ft off the floor. You can stand on the couch and feel the air is warmer higher up higher, as it should be. I don't have an IR thermometer but I'd assume the ceiling is 80°plus in that room. I run the HVAC fan and I get nothing but cool air coming out of the vents. I let it run for a couple of hours once thinking I just needed to heat up the ducts but the air never got warmer. I will get an IR thermometer to confirm my findings one day. Maybe when my insert gets installed and I can get the ceiling of that room to closer to 90° it will work better.
I have had better luck just leaving all the doors open and running fans. One room on the same floor but opposite end of house I just have a ceiling fan on low in reverse. Another room upstairs I have a box fan in the door blowing toward the fire. With my open fireplace I can get the whole house above 64° when it is below freezing out. Everyone still complains it is too cold in the house and hates when I light a fire. Oh well it's free heat (though most is being wasted up the chimney).
I have had better luck just leaving all the doors open and running fans. One room on the same floor but opposite end of house I just have a ceiling fan on low in reverse. Another room upstairs I have a box fan in the door blowing toward the fire. With my open fireplace I can get the whole house above 64° when it is below freezing out. Everyone still complains it is too cold in the house and hates when I light a fire. Oh well it's free heat (though most is being wasted up the chimney).
moving the heat around is tuff, I have had my basement in the mid 80s and the upstairs stays 62. as others have said, fans on floor moving cold air towards the heat source is your best bet.
So everyone is saying have a fan pointed towards the stove, not away from it? I would think having a fan in the hallway blowing towards the bedrooms would pull the warm air to the rooms? Also the ceiling fan on reverse so it is blowing air up and not down?
barnaclebob
Feeling the Heat
Ceiling fan going clockwise to blow air up. Like others, I have a small fan at floor level blowing towards the stove room. Experiment with a box fan on high to see the quickest results.
The natural convection loop, with no fans, will be that the warm air in the stove room rises since it is lighter and flows out the top of the stove room door opening, and cool air flows into the room down low to replace it. Putting a small 8" fan on the floor on low will move the dense, cool air toward the stove room, boosting the natural convection loop. A ceiling fan in the stove room will disrupt the natural stratification of warm air to the top of the stove room and will weaken the natural loop. You can tape strips of tissue paper in the tops of doorways to see how much warm air is flowing to the back rooms, then experiment with fan placement to see what works best. If your floor fan will pivot down, you can use it in a stairway to move cool air down from upstairs.
There was a ceiling fan in the stove room at my MIL's house but the only way to be comfortable in the room was to leave it off and let the warm air stratify..then you could sit in the chairs without roasting, and the warm air would flow out the top of the doorway.
Vaulted ceilings trap a lot of hot air but if you let it stratify, it will get to the top of the doorway to some degree and flow out.
Your experience notwithstanding, or course.
Not sure how much you have experimented with the tissue paper to see how much air is moving..?
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kennyp2339
Minister of Fire
@Woody Stover you sure upped your game this year by using those big fancy words lol.
Are you flummoxed by them?
I certainly do like words but I'm just trying to write so that it's more understandable. However, it can end up being a bit drawn out, with some run-on sentences. I'll try to do better.
If I start talking without filling in the details first my wife will say "That's all well and good, but what the hell are you talking about??"
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Sawset
Minister of Fire
I tried it too, moving air from warm to cooler rooms using the hvac fan and ducting. I even put extra "cold air" return registers in the stove room area to try to pull warm air into the system. Ended up doing nothing. Two story house 2000sqft, no vaulted ceilings, typical furnace in the basement. The thing is hvac systems are designed around a significant temperature boost as it goes through the furnace, either for heating or cooling. That isn't the case when just moving room air around from place to place. In order to get the bedrooms up to 65 or 70, it would take an air flow of 100-120deg air to make that happen if the outside temps were fairly cold. Blowing 75-80deg air into a cold room at the rate hvac ductwork will, just blows weak low volume warm air into a room full of cold air resulting in - cold air.
A properly installed HVAC system is balanced. Blocking returns or supplies is not a good idea. It can cause the blower to race and lead to premature burnout.
If I decide to block return grills permanently or at least winter months I would install a Manomter on my air return near the furnace and add a return if needed on the first floor to keep the system balanced.
Mech e
Feeling the Heat
I would never block off return air registers. However, "tweaking" supply registers can be done within reason (that needs to be defined) as long as the system is not a heat pump. If you have a heat pump and are restricting supply or return registers and forget to open them when you want to run in the heating mode, very expensive damage could occur to the system compressor over time.
I like many have tried to use my HVAC system with no Luck. I have a 2400 square foot ranch. The stove sits at one side of the house. It is a Drolet insert. I currently have two heat pumps with no propane back up. I have placed two small fans on the floor facing the stove room. One in the back hallway that pushes air into another fan that is pointed into stove room ( 12 foot ceilings). Currently able to keep front half of house at 70 and back rooms at 65. This took many hours of playing around with moving air outside the stove room. I tried fans in the corners of the doorways, using HVAC system. All with no to little luck. Two fans on low feeding cold air into stove room is what did it. Burning perfectly seasoned wood is also a key to having success..
I have opened and closed many dampers on air supply return to the unit and discharge air on commercial units I with little to know problems but I monitor pressures. If you get a good vacuum reading on your return as system is designed and maintain that there should not be a problem. I have used Manometers to check air flow thru filter banks.
Grizzerbear
Minister of Fire
I use my hvac fan more or less to help cool down the stove room if it gets a lil too balmy and it seems to help heat the bedrooms. I have a small 1500 sq ft single story house with ductwork in crawlspace that stays around 50 degrees. That being said i also use a fan in doorway floor of master and like everyone else i think this works best. I do think running the hvac fan helps heat the ducts which help keep crawl warmer on those frigid nights but it might be negligible. Makes me feel better about chances of pipes freezing though.
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