Wood Stove Insert Size

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CTwoodinsert

New Member
Mar 30, 2023
3
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.
 

begreen

Mooderator
Staff member
Nov 18, 2005
99,743
South Puget Sound, WA
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.
 

CTwoodinsert

New Member
Mar 30, 2023
3
Stamford, CT
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?
 
Last edited:

begreen

Mooderator
Staff member
Nov 18, 2005
99,743
South Puget Sound, WA
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?
 

CTwoodinsert

New Member
Mar 30, 2023
3
Stamford, CT
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
 

begreen

Mooderator
Staff member
Nov 18, 2005
99,743
South Puget Sound, WA
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.