Variable Speed Blower for Fireplace question....

[mtj53]

Another question for you guys! I am looking currently at purchasing an RSF Opel, or possible a Quadra-Fire 7100 wood burning fireplace. I talked with the man that sells the RSF today-he looked over everything I have, and If I go with him, we'll hook right into my ductwork. The furnace I currently have is an 18 year old Heil furnace, it does not have a variable speed blower, and he thinks I would really need that variable speed blower instead of letting my current blower run all out, all next heating season 24/7. He wasn't aware of a replacement blower that would be variable speed that would work with my furnace. I was wondering if anyone else on the board here has run into that at all? If so, how did you or how would you work around that? Thanks!

 

[begreen]

Have you considered ducting the fireplace independently with it's own remote blower? Dumping it into the old system might introduce a lot of inefficiencies unless the ductwork is all sealed and well insulated.

 

[mtj53]

As I understood the RSF salesman, the RSF fireplace will have a small blower approximately 1/3 the size of my furnace blower, but he said that alone wouldn't be enough to spread the heat everywhere I need. The ductwok I have is nice and tight but not insulated. I probably would consider putting new ductwork in just for the fireplace, but I would be trying to heat a closed area on the second story as well, so it wouldn't be practical to run the ductwork all the way to the second story would it? And I know heat rises but ducting to a room on the first floor won't heat up a room on the second floor all that much would it? He had told me that I could just run my current furnace fan continuously, but he also mentioned that it would probably drive us crazy after awhile having the fan blowing 100% of the time and it would use alot more electricity.

You bring up a great point though, perhaps I should consider running ductwork for the first floor--if I did that, and say a room on first floor was 72 degree's, would you want to take a guess how much of that would transfer upsatirs through the ceiling?

 

[73blazer]

It's a manual solution, but there are usually blower taps on furnace boards.
Low, med, med-high and high. They usually plug the ac call into the high and the heat and fan only into med-high. It's a board usually in the motor compartment.
You could switch the blower tap to low. Some furnaces have a fan-only tap, so you would plug that wire into low and you'd be set. But most don't. So you'd have to take the heat tap and plug it to the low tap.
But BEWARE, if you do that, then your temperature rise for the furnace will be way to high when you run the furnace (meaning, not enough air blowing over the heat exchanger and it may cause damage eventually that way). So you would have to switch it back to it's currently set tap to use the furnace. If you were handy, you could run some 14ga wire to a switch somewhere to easily switch it from heat pos to fan pos and have the fan on low. Or even better, buy a 24vac activated relay that can switch 120v and wire it up to the fan call. THen you could have the fan call automatically use the low tap and the heat call automatically use the tap it's currently on.

I wouldn't do this unless you really never use the furnace, it's a hack, and if you forget to put it back to it's right tap or don't use the automatic relay method, for the furnace to run, there could be trouble, but it's possible.

 

[begreen]

As I understood the RSF salesman, the RSF fireplace will have a small blower approximately 1/3 the size of my furnace blower, but he said that alone wouldn't be enough to spread the heat everywhere I need. The ductwok I have is nice and tight but not insulated. I probably would consider putting new ductwork in just for the fireplace, but I would be trying to heat a closed area on the second story as well, so it wouldn't be practical to run the ductwork all the way to the second story would it? And I know heat rises but ducting to a room on the first floor won't heat up a room on the second floor all that much would it? He had told me that I could just run my current furnace fan continuously, but he also mentioned that it would probably drive us crazy after awhile having the fan blowing 100% of the time and it would use alot more electricity.

You bring up a great point though, perhaps I should consider running ductwork for the first floor--if I did that, and say a room on first floor was 72 degree's, would you want to take a guess how much of that would transfer upsatirs through the ceiling?

Without knowing a lot more about the house, it would just be a wild guess. In some cases, like our house, the heat migration to upstairs is great. In others it's not so good. If you can post floor plans that would help.

 

[mtj53]

Begreen,
Here are the basic floorplans of my house, as well as some pictures taken from inside and outside which will hopefully show you the layout as good as possible. The reason I have been thinking I need to hook up to my heatducts is because if you notice, the one picture was taken with me standing inside my front door looking up to the single doorway upstairs, that doorway leads into the largest part of the upstairs area which is the master bedroom, closet & bathroom. That area is colder now even with heat ducts heating it. Here are some links to pics, each picture has a description:
http://i405.photobucket.com/albums/pp135/mtj54/1stfloor.jpg 1st Floor layout
http://i405.photobucket.com/albums/pp135/mtj54/2ndfloor.jpg 2nd floor layout
http://i405.photobucket.com/albums/pp135/mtj54/fromfireplace1.jpg fireplace to front door pic.
http://i405.photobucket.com/albums/pp135/mtj54/fromfireplace2.jpg fireplace towards dining room
http://i405.photobucket.com/albums/pp135/mtj54/fromfireplace3.jpg fireplace towards loft area
http://i405.photobucket.com/albums/pp135/mtj54/frontdoortowardsFP.jpg front door towards loft area
http://i405.photobucket.com/albums/pp135/mtj54/frontdoortoupstairs.jpg front door to upstairs doorway
http://i405.photobucket.com/albums/pp135/mtj54/home2007f-1.jpg back of house pic
http://i405.photobucket.com/albums/pp135/mtj54/houseapril2006.jpg front of house pic

Statistics:
1640 SQ FT downstairs
860 SQ FT upstairs
fireplace to center of living room is 39 feet
fireplace to center of open doorway into kitchen is 18 feet
add another 11 feet to get to center of kitchen
add yet another 16 feet to get from center of kitchen to center of laundry room.
I know the fireplace will heat the room it is in, as well as the dining room straight ahead of it, possibly the kitcjhen? and I am sure it'll keep the upstairs smaller bedroom and loft area warm, my concerns would be will the laundry room be cold, and also without running thru ductwork, will that whole upstairs Master bedroom/bathroom closet area be extremely cold--that area covers 16 ft wide by 34 feet long with only one 36 inch walk in door leading into it. make any sense? Thanks so much for taking a look at it and giving me your opinion...

 

[21acrewoods]

I see your delima. Have you considered floor registers like I've seen in some old houses that just puts a hole in the ceiling that goes right upstairs with a register on the ceiling and floor upstairs? If that is your master BR upstairs you would lose some privacy. I think your upstairs bath would stay warm if the doors were left open.