EPA Efficiency Rating Vs Manufacturer's

[billfrommissouri2]

I selected a new stove with an advertised efficiency rating of above 80%. When I get it in the back of my truck I see an EPA tag saying it has 64% efficiency.

With BTUs the manufacturer claims 50,000. The EPA tag says 50%

What's up?

 

[SmokingAndPoking]

A lot of funny business is at play here.

The EPA tag probably says 63% efficiency, which is the default for non-catalytic stoves (pellet stoves currently fall under that category). This is a "given" value and doesn't reflect a calculated value.

Also, the BTU rating on the EPA tag is found using that 63% efficiency. In reality, if the stove is around 80% efficient, use the formula:

8600 BTU/lb x .80 x max lb/hr feed rate


There are different ways of measuring stove efficiency, so that 80% could be plus or minus 5% or more.

 

[billfrommissouri2]

Shwew. So maybe my stove really will be "80%" efficient.

Anyway, I admire your flue pipe, burning chuck. You must be burning close to 100%.