Hi all,
I am in the process of installing my pellet furnace as an add-on to my oil furnace. Hopefully, it will help someone else learn from my mistakes. : )
Here's what I started with:
There was originally a wood furnace in this spot. It sat there for years unhooked and with stuff being piled around it, I never knew we had a well in the basement. If I had started this project when I wanted to, (late Spring) I might have tried to dig down to see if there was anything worth finding. Unfortunately for now, the buried treasure will have to remain buried:
I hated to do it but with cold settling in I have to get to going. I poured the cement Sunday night and let it cure till today. I used a plastic pan similar to the pink one in the background. Actually the white pan in the next picture is the one I used. It took 5 80# bags of high strength concrete mix. I could get almost 1/3 of a bag mixed in that tub but still took a while. The pad is about 3 feet by 42 inches by about 3.5" thick. I was originally going to position the furnace perpendicular to the oil furnace but had second thoughts as I looked at the set up. I was thinking to cut into the side of the oil furnace and share the cold air duct that way.
I changed my mind for several reasons:
1. I'm concerned that if the oil furnace comes on at the same time on a really cold day, it will
affect the draw for the pellet burn, maybe causing incomplete combustion and making a bunch
of smoke.
2. The access panel for the pellet stove electronics is in the rear of the unit. I could probably still
access everything but why make it harder than I have to?
3. I would have had to duct the hot air back about 3 foot, right over the hopper which I have the
extension to hold 70 # of pellets. The extension sticks up about 15 inches so the hot air would
a lot of traveling to do before it got to the main plenum.
So I now have the stove in this position, looking at the front:
Sorry for the dark picture. I haven't figured out how to use my fancy camera yet. : ) Here's a picture of the heat exchanger tubes. Again it's a dark picture but if you look closely you can see that the edge of the first tube is flush with the main plenum:
I'm considering moving the furnace further back so that the exchanger tubes are more centered with the main plenum. That way I would get the most efficient heat transfer into the existing ductwork. The problem is that the rear of the furnace is right on the edge of the pad:
I would have to move the furnace about 2 or so to align the edge of the exchanger tube more inward from the edge of the plenum. I'm not sure the gain is worth it though or if it would be noticeable. I'm thinking of using blueboard or something similar to make the hot air duct with to keep heat loss to a minimum.
On the rear of the furnace, the manual is not clear how they ducted to the main furnace. It looks like they basically built a duct box that goes from one furnace to the rear of the other. At least that's what it looks like. I'm thinking that I'm just going to tape a filter over the opening of the pellet furnace cold air intake and just use the air from the unheated basement for the time being:
I don't want to tie it into the oil furnace for the above reason that if the oil furnace kicks on, I'm afraid it will draw too much away from the pellet burn, causing incomplete combustion and making a bunch of smoke.
The exhaust isn't too terrible to hook up to, I just have to get some fittings and goof around a bit:
The plenum has 8 ducts coming off it. I'm thinking I'm going to remove 4 of them and leave those rooms unheated. I'm single, no family so I don't need the whole house to be heated. The unheated rooms all have doors so I can just keep them closed.
I am waiting for a pair of circuit breakers I bought off ebay to arrive so I can start wiring in. I've got a thermostat too and I have to get some wire for that. I'm thinking that I will keep the oil furnace at 50 and the pellet stove at 60. I suffered last winter at 50 and I want a bit more heat this time around. : ) I might even go to 65 if it works out. I'm thinking of replacing the ducts with flex duct too.
Any comments / suggestions most welcome. I'm not a pro at this stuff.
Wayne
I am in the process of installing my pellet furnace as an add-on to my oil furnace. Hopefully, it will help someone else learn from my mistakes. : )
Here's what I started with:
There was originally a wood furnace in this spot. It sat there for years unhooked and with stuff being piled around it, I never knew we had a well in the basement. If I had started this project when I wanted to, (late Spring) I might have tried to dig down to see if there was anything worth finding. Unfortunately for now, the buried treasure will have to remain buried:
I hated to do it but with cold settling in I have to get to going. I poured the cement Sunday night and let it cure till today. I used a plastic pan similar to the pink one in the background. Actually the white pan in the next picture is the one I used. It took 5 80# bags of high strength concrete mix. I could get almost 1/3 of a bag mixed in that tub but still took a while. The pad is about 3 feet by 42 inches by about 3.5" thick. I was originally going to position the furnace perpendicular to the oil furnace but had second thoughts as I looked at the set up. I was thinking to cut into the side of the oil furnace and share the cold air duct that way.
I changed my mind for several reasons:
1. I'm concerned that if the oil furnace comes on at the same time on a really cold day, it will
affect the draw for the pellet burn, maybe causing incomplete combustion and making a bunch
of smoke.
2. The access panel for the pellet stove electronics is in the rear of the unit. I could probably still
access everything but why make it harder than I have to?
3. I would have had to duct the hot air back about 3 foot, right over the hopper which I have the
extension to hold 70 # of pellets. The extension sticks up about 15 inches so the hot air would
a lot of traveling to do before it got to the main plenum.
So I now have the stove in this position, looking at the front:
Sorry for the dark picture. I haven't figured out how to use my fancy camera yet. : ) Here's a picture of the heat exchanger tubes. Again it's a dark picture but if you look closely you can see that the edge of the first tube is flush with the main plenum:
I'm considering moving the furnace further back so that the exchanger tubes are more centered with the main plenum. That way I would get the most efficient heat transfer into the existing ductwork. The problem is that the rear of the furnace is right on the edge of the pad:
I would have to move the furnace about 2 or so to align the edge of the exchanger tube more inward from the edge of the plenum. I'm not sure the gain is worth it though or if it would be noticeable. I'm thinking of using blueboard or something similar to make the hot air duct with to keep heat loss to a minimum.
On the rear of the furnace, the manual is not clear how they ducted to the main furnace. It looks like they basically built a duct box that goes from one furnace to the rear of the other. At least that's what it looks like. I'm thinking that I'm just going to tape a filter over the opening of the pellet furnace cold air intake and just use the air from the unheated basement for the time being:
I don't want to tie it into the oil furnace for the above reason that if the oil furnace kicks on, I'm afraid it will draw too much away from the pellet burn, causing incomplete combustion and making a bunch of smoke.
The exhaust isn't too terrible to hook up to, I just have to get some fittings and goof around a bit:
The plenum has 8 ducts coming off it. I'm thinking I'm going to remove 4 of them and leave those rooms unheated. I'm single, no family so I don't need the whole house to be heated. The unheated rooms all have doors so I can just keep them closed.
I am waiting for a pair of circuit breakers I bought off ebay to arrive so I can start wiring in. I've got a thermostat too and I have to get some wire for that. I'm thinking that I will keep the oil furnace at 50 and the pellet stove at 60. I suffered last winter at 50 and I want a bit more heat this time around. : ) I might even go to 65 if it works out. I'm thinking of replacing the ducts with flex duct too.
Any comments / suggestions most welcome. I'm not a pro at this stuff.
Wayne
