# Calculating a Stove's BTU/hour

#### Karottop

##### New Member
I've recently installed two wood stoves in my house. The upstairs stove is an Osburn 1600 insert and the basement stove is Buck Stove model 80.

The buck stove is gigantic - it barely fit in my fireplace and has a 2.6 cu/ft firebox
The Obsburn looks newer but only has a 1.8 cu/ft firebox

Whats odd is the EPA rating for the buck stove is ~40,000 BTUs per hour and the Osburn is 65,000 BTU's per hour. How does that little Osburn stove put out ~50% more heat than the Buck Stove?

To confuse the situation even more, the Buck Stove is rated to heat anywhere from 1800-2600 sq/ft, while the Osburn is rated for 1800 sq/ft? it apparently puts out more heat per hour but is rated for a smaller house? I'm a little confused - thanks for any help..

I think you may be mixing peak output with EPA tested output. They are not the same. The Buck 80 is EPA rated at 9200-40500 BTUs/hr and the Osburn 1600 is rated at 11,800 to 42,400 BTUs/hr. 65,000 BTUs is peak output which is more marketing than real world. They are also two different technologies - cat vs non-cat. The Buck's output will be more steady and sustained over a longer period of time than the brief peak output of the Osburn.

I think you may be mixing peak output with EPA tested output. They are not the same. The Buck 80 is EPA rated at 9200-40500 BTUs/hr and the Osburn 1600 is rated at 11,800 to 42,400 BTUs/hr. 65,000 BTUs is peak output which is more marketing than real world. They are also two different technologies - cat vs non-cat. The Buck's output will be more steady and sustained over a longer period of time than the brief peak output of the Osburn.
Ah, ok I didn't realize there was a difference. That makes a lot more sense, thank you!