Circulating warm air to other rooms?

[JFerg65]

Last night I put a small fan in my hallway and just pointed it down the hall back to the end of the house where the stove is. WOW! that is the trick!! my daughters room went from 64 to 69 in about an hour. You could really feel the warm air heading down the hall to the back bedrooms.
THANKS for the IDEA!! We are now set.

 

[Wirenut2266]

Numnuts: First of all I like the name! Next, did you install vent pipe in attic? If so, did you bury in insulation or other? Just curious, I may do something like you did in summer?

I had the same issue, although we are in a 1 level ranch style home. My solution, albeit rather involved, works fantastically. I bought a Panasonic FV-40NLF1 8" inline vent blower. Very quite and very efficient (132W 120V). Had I known, I would have gotton a smaller blower, 440 CFM is way too much and had to throttle it down. The ceiling in the living room (where the stove is) is vaulted so it collects heat real well. I installed a 12" sq intake duct at the peak of the ceiling and then distrubute via 4" ducts to small registers in each bedroom. I have it thermostatically controlled so when the room heats up, the fan turns on. If the fire burns down and the room cools down, the fan turns off. Really sweet setup that has allowed me to not run the furnace yet this year. People are pretty impressed with how even the temp is in our house.

 

[olyman]

When I was a kid our farm house had grates in the floor upstairs in every room. We had an old pot belly in the basement with a 5x5 grate over it.Our whole house heated on gravity.

convection--

 

[skmag357]

I had the same issue, although we are in a 1 level ranch style home. My solution, albeit rather involved, works fantastically. I bought a Panasonic FV-40NLF1 8" inline vent blower. Very quite and very efficient (132W 120V). Had I known, I would have gotton a smaller blower, 440 CFM is way too much and had to throttle it down. The ceiling in the living room (where the stove is) is vaulted so it collects heat real well. I installed a 12" sq intake duct at the peak of the ceiling and then distrubute via 4" ducts to small registers in each bedroom. I have it thermostatically controlled so when the room heats up, the fan turns on. If the fire burns down and the room cools down, the fan turns off. Really sweet setup that has allowed me to not run the furnace yet this year. People are pretty impressed with how even the temp is in our house.

This is exactly what I planned on doing at my house. I wasn't sure what size fan to use. I only really care about heating my bedroom and the bathroom upstairs. There is a floor joist that runs down from the stove to the bedroom and bathroom. How far are you moving the air from the stove? what size fan would you recommend? when you installed the intake, was the fan directly behind the register? Is the thermostat included with that fan or did you have to purchase seperately? Can you pm me the full list of everything needed for the project? I would greatly appreciate it as I have vaulted ceiling as well so it would be perfect...thanks!

 

[046]

sounds like a slick solution!!!

I had the same issue, although we are in a 1 level ranch style home. My solution, albeit rather involved, works fantastically. I bought a Panasonic FV-40NLF1 8" inline vent blower. Very quite and very efficient (132W 120V). Had I known, I would have gotton a smaller blower, 440 CFM is way too much and had to throttle it down. The ceiling in the living room (where the stove is) is vaulted so it collects heat real well. I installed a 12" sq intake duct at the peak of the ceiling and then distrubute via 4" ducts to small registers in each bedroom. I have it thermostatically controlled so when the room heats up, the fan turns on. If the fire burns down and the room cools down, the fan turns off. Really sweet setup that has allowed me to not run the furnace yet this year. People are pretty impressed with how even the temp is in our house.

 

[bwmcintyre]

Numnuts - I've thought of doing the exact same thing in our house. A ceiling fan does well to move some of the air towards the hall where our bedrooms are, but our master bathroom and one of the rooms at the corner of the house suffer from lack of heat. Nothing like getting a shower on a cold day when the temp in the bathroom is in the 50s ... brrr.

 

[JFerg65]

Not to beat a dead horse here but before you go and drop all that coin into a duct system, you should really try the pointing a small fan on the floor near the rooms or rooms you are trying to heat and point it down the hall back toward the stove. We have our two rooms that prior to doing that we had a hard time getting above 65. With a hot stove and the fan, the rooms stay right at 70 degrees, all for a $15.00 fan on low. The next thing will try to find one that is efficient as possible.

 

[mga]

if your wood burner uses a blower that draws air from the same room, run duct from a far end of the house so that it draws the cold air from that room into your wood burner.

 

[numnuts]

This is exactly what I planned on doing at my house. I wasn't sure what size fan to use. I only really care about heating my bedroom and the bathroom upstairs. There is a floor joist that runs down from the stove to the bedroom and bathroom. How far are you moving the air from the stove? what size fan would you recommend? when you installed the intake, was the fan directly behind the register? Is the thermostat included with that fan or did you have to purchase seperately? Can you pm me the full list of everything needed for the project? I would greatly appreciate it as I have vaulted ceiling as well so it would be perfect...thanks!

I am running the ducting to 3 bedrooms. The furthest(and coldest in more than one way) is the master bedroom, it is about 30' from the intake duct. I bought 1/2" foam board that has thin foil on 1 side to make my intake and exhaust plenums. The intake utilizes a 12" x 12" filter and grate(a filter here is strongly recommended after plugging one in 1 season!). Then I ran 8" ducting to the fan somewhat centrally located to the 3 rooms (all of this is obviously in the attic). On the outlet side of the fan I built and mounted another plenum which has 3 - 4" outlets. Those run to 4" x 6" (I think) registers in the ceiling of the respective bedrooms. I used flexible, insulated ducting. I used a whole box to run the 8" from the intake to the fan, 25' per box I believe. It then worked out that a 25' box of 4" was just enough to run to the 3 rooms. Eveything but the fan and thermostat were purchased at the big orange box store.

I have learned that you really want to try and keep the length of the outlet ducts as close to the same to balance flow and noise. For my application, a 440 CFM fan is waaaay more than enough, probably 1/2 that would be sufficient, but I was sailing uncharted waters and took a guess thinking the bigger the better. Anyway, I ended up installing a fan speed control to slow the sucker down. As mentioned speed is not paramount, and the noise of all that air running through the register was a bit much....the fan is real quiet, but the rushing air is not when turned up all the way.

The thermostat is a great idea, in theory. Unfortunately it didn't work as planned. I used a 110V A/C thermostat and I think I either have it mounted in a poor location or it just isn't sensative enough. I think the latter is more than likely. The idea is that, say it is set at 70°. When the living room gets to setpoint, the thermostat thinks you want to cool it down, and turns the fan on. It should stay on as long as the stove is putting out heat and the room is more than setpoint. Once the fire goes out and the temp drops sufficiently enough, it will turn off the blower. I have since removed the T-stat and replaced it with the fan speed controller like you would use to control a ceiling fan. I may look into a real thermostat in conjuction with a relay to control the fan. I believe most home thermostats use 18V(?) to control relays to turn on/off the various HVAC systems, so there's a little more BS associated with installation of that system. My stove fan is also thermostatically controlled. When the fire goes out, usually about 3 or 4 AM, and the stove cools down to about 100°, it turns off. The the room temp will drop below setpoint and turn the fan off so you are not circulating cool air. That's how it works on paper.

I had the stove for 2 years before the fan and it was never real comfortable in the house. It was smoking hot in the living room and freezing in the bedrooms. Mama was not happy. The fan installation has really made a huge differance in the balance of the temp in the house. The kitchen and dining rooms are adjacent to the living room so the temp is not an issue there.

If there's enough interest I could probably drag my butt up there for some pics of my setup.

As if this response wasn't long enough.....opcorn:
I did all this right before Christmas of 2008. I had just completed renovating the living room, which consisted of scraping the popcorn texture off the ceiling, plugging the 9" square ceiling light holes, and installation of can lights, and a whole lot more. Anyway, the actual fan / plenum / ducting was done on Christmas eve. As I was traversing across the vaulted ceiling I stumbled and guess what....I made a new access point to the living room from the attic through my freshly completed ceiling.:jawdrop: I wasn't hurt physically, but a man will go through an enormous range of emotions when he has just ruined a project that took several weeks to complete. Nothing is better than blasting off to HD to get a sheet of sheetrock 5min. before the store closes and doing a little sheetrock on Christmas eve! Got the hole plugged before Santa showed up.

That's enough....

 

[bwmcintyre]

As I was traversing across the vaulted ceiling I stumbled and guess what....I made a new access point to the living room from the attic through my freshly completed ceiling. I wasn't hurt physically, but a man will go through an enormous range of emotions when he has just ruined a project that took several weeks to complete. Nothing is better than blasting off to HD to get a sheet of sheetrock 5min. before the store closes and doing a little sheetrock on Christmas eve! Got the hole plugged before Santa showed up.

Oh man .. I can identify with this one! One of the early trips I made up into our attic space included an extra "vent" being created by my foot. Fortunately, it was in the utility room, not the most visible part of the house. I still get crap about it every time I have to get up there for something.

I really appreciate the info you shared .. as I have thought about doing the exact same thing, but wondered how effective it would be. The other suggestions about using a fan are great, but due to the layout of the rooms, wouldn't be as effective.

 

[Techstuf]

Our stove sits in an unfinished basement and heats the whole house, all three levels, (including basement) around 2650sqf. If one has central air, it is not all that complicated to make a metal shroud around part of the stove with a bit of stove pipe plumbed into the system. Furnace fan will draw air over and around the stove, providing plenty of heat. Get yourself an 'aircycler', which is simply a timer for running the central air fan at programmed intervals. Since our main floor already stays toasty via heat conducted through the floor and sent up the main stairwell, we cover half of all return air ducts, and close the vents to all but the coolest room on the main floor and the second floor.


Works great with hardly a noticeable difference on electric bill.



Blessings in Christ Yeshua

 

[CrappieKeith]

Hey numnuts....you been messing around dingeryote?...just asking cause with a handle like that I figured you been splitting wood with him or something?

 

[numnuts]

Hey numnuts....you been messing around dingeryote?...just asking cause with a handle like that I figured you been splitting wood with him or something?

No, but if he's offering to help, I'm all in. The fact that I came through the ceiling might be foretelling.....

 

[skmag357]

well a year later I finally installed my air moving system. I have an intake above the stove with 220 cfm fan connected to 20 feet of insulated ductwork that runs to our bedroom. There is one S bend to get through a rafter and a slight rise into our room. The problem is that there is hardly any air flow in our room and any air that comes out it is cold....any suggestions? The fan is directly behind the intake as well

 

[jimdad07]

Glad to hear you got it in. You say there is little air flow in your bedroom? Is this with the door closed? If it is you might have static pressure built up, meaning if the air can't get out, then it won't bring it in. As far as the cold air goes, you may be moving it too fast and it is cooling down by the time it gets to your room. Trying to circulate warm air from your woodstove is not like pushing hot air off of a heat exchanger in a furnace, it is not nearly as hot and it needs a much lower cfm to keep it from cooling down too much.

 

[skmag357]

I went off the earlier recommendations of lowering the cfm to 220 vs 440. The door is open from our bedroom but that doesn't seem to help. Does the number of turns or the angle of the turns reduce both air speed and temp??

 

[RacerX]

Many of these attic ducting scenarios sound great but installing the vents in the ceiling is not the most efficient use of the heat. The duct should run down from the attic in the wall and the vents should be down near the floor. That does create a problem with trying to blow the warm air down however.

 

[Billy_Bob]

I use fans, doors, the weather forecast, and indoor/outdoor thermometers.

Fans to circulate heat to other rooms.

At night, if it is going to be real cold, I heat up the living room real good, then close the bedroom door so I don't roast myself. Then in the morning the living room will be somewhat warm. Might open the bedroom door in the early morning if I get cold.

And if I should build a big fire or not before going to bed... This depends on the weather forecast and the outside temperatures.

Also same with during the day. If it is supposed to be cold that day, I'll keep a good fire going. If it is supposed to be warm, then I will let the fire burn out.

And if I'm not using the living room, I might build a big fire and use fans to circulate the heat to other rooms. Then if I go back in the living room and it is hot as can be, I'll open the front door to cool off the living room.

I guess I've learned how much heat loss the house has. And depending on where the outside temperature is heading, I can predict in advance how big of fire to build.

 

[jimdad07]

I went off the earlier recommendations of lowering the cfm to 220 vs 440. The door is open from our bedroom but that doesn't seem to help. Does the number of turns or the angle of the turns reduce both air speed and temp??

The number of elbows does have an effect on the air movement, but from what you have it doesn't sound like it should be a major deal. I bet if you put a temp probe in the supply air in your bedroom, I bet you will be reading in the mid to high 70's if you are taking air from above your stove. Anything below body temperature will feel cold coming ouit of the supply blowing on you.

 

[mga]

well a year later I finally installed my air moving system. I have an intake above the stove with 220 cfm fan connected to 20 feet of insulated ductwork that runs to our bedroom. There is one S bend to get through a rafter and a slight rise into our room. The problem is that there is hardly any air flow in our room and any air that comes out it is cold....any suggestions? The fan is directly behind the intake as well

not going to work.

you'd be better off using that fan to draw the cold air OUT of the rooms and onto your wood burner. as others suggested, let the negative pressure draw the warm air into the rooms.

there's a different science going on than trying to heat a house like a gas furnace.