Wood Stove Insert Size

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CTwoodinsert

New Member
Mar 30, 2023
46
Stamford, CT
Hi Everyone,

I am new to wood stove world and looking install an insert to my fireplace. I live in New England, winters get pretty cold. I have a small ((1,553 sq ft) older cape that is two story and not insulated. The room fireplace is in first floor that is connected to chimney and fairly big and there are two openings that goes to dining room and kitchen. I am looking to install either Osburn Matrix or Osburn 3500. Both units are high efficiency Matrix outputs 75,000 BTU (79% efficiency) and 3500 outputs 110,000 BTU (77% efficiency). I am in between as 3500 has more cubic ft and glass area that will radiate heat better compared to Matrix however not sure if it is necessary.

Considering i don't have insulation and looking to use wood stove insert to heat the whole house including upstairs do you recommend I go with Matrix that outputs 75,000BTU or with Osbourn 3500 that outputs 110,000 BTU with bigger glass.

Thanks in advance for your help.
 
I'd go large with the 3500. It'll need fully seasoned firewood to perform well.
I have to say, insulating the house could possibly be a better investment. It will pay back year-round for the cooling season as well as the heating season.
 
I'd go large with the 3500. It'll need fully seasoned firewood to perform well.
I have to say, insulating the house could possibly be a better investment. It will pay back year-round for the cooling season as well as the heating season.
Thank you for your response and recommendations. Can I heat the whole house with Matrix or only way is the 3500. I don’t want to over do it but knowing winters get really cold with no insulation I want to get the right unit. Will the burn time gonna be longer in the bigger unit?
 
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Thank you for your response and recommendations. Can I heat the whole house with Matrix or only way is the 3500. I don’t want to over do it but knowing winters get really cold with no insulation I want to get the right unit. Will the burn time gonna be longer in the bigger unit?
How is the house now heated? How wide are the fireplace room openings to the rest of the house? How frequent are power outages?
 
How is the house now heated? How wide are the fireplace room openings to the rest of the house? How frequent are power outages?I
I use oil to heat the house right now. Power outages are not frequent. We only had three outages in the last 5 years. The openings are roughly 3.5 to 4ft. Is bigger unit means longer burn time? The installer told me Osburn Matrix will have max 4 to 5 hour burn time because house would get too cold if we don’t turn on the oil boiler. Spec sheet says max burn time of 8 hours? Is that makes sense?

Thanks
 
I use oil to heat the house right now. Power outages are not frequent. We only had three outages in the last 5 years. The openings are roughly 3.5 to 4ft. Is bigger unit means longer burn time? The installer told me Osburn Matrix will have max 4 to 5 hour burn time because house would get too cold if we don’t turn on the oil boiler. Spec sheet says max burn time of 8 hours? Is that makes sense?

Thanks
The burn time is going to be relative to the wood, draft, and stove operation. When the heat demand is low to moderate, then 8 hr burn times in the Matrix can be achieved, you might even see some 10 hr burns. When the demand for heat is high that might drop down to 4-6 hrs between reloads.

During a power outage, the 3500 will do a better job of heating. The Matrix is a flush insert and it will be more dependent on the blower to convect the heat. The 3500 projects out onto the hearth which helps it radiate heat as well as convecting it with the blower.
 
I went the matrix insert and insulated the house this summer. however the unit is not putting out much heat. It barely warms up the room it is in. What may cause this issue it was professionally installed. My house is 1543 sq ft and first floor is only 800. Unless I sit infront of the insert you can’t feel the heat, blower is very weak and blowing vertically. Place I bought from and installed not taking any responsibility. I am using seasoned wood. What may cause this issue since all it is a welded box. Attached is the picture of my chimney

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Is the chimney on an interior or exterior wall? If exterior, did the installer insulate the back and sides of the fireplace with Rockwool insulation and did they install a blockoff plate above the insert?

If the answer to those last two questions is no, you are likely losing most of your heat up the chimney and through the back of the masonry chimney.
 
Is the chimney on an interior or exterior wall? If exterior, did the installer insulate the back and sides of the fireplace with Rockwool insulation and did they install a blockoff plate above the insert?

If the answer to those last two questions is no, you are likely losing most of your heat up the chimney and through the back of the masonry chimney.
Unfortunately answer is no. Exactly what you said is happening. He didn’t do correct installation
 
When I installed my insert, I used that foil faced Roxul on the back and sides of my fireplace, and I also made a blockoff plate above it with the same stuff. I bet this would help a lot if you have room to install it.

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You can see that I also fully taped all the seams with foil tape as well.