Since when is the EPA in the thermal transfer efficiency business. Sniffing the stack is their domain. They don't test thermal transfer efficiency of wood stoves that stand in the living space. What would any numbers about it in a shack away from the house have to do with anything? What gets into the living space is the only thing that counts. Yeah. I am ass deep familiar with EPA Method 28 for stoves. But it looks like now I have to go dig through the version for boilers. But Method 28 for stoves has not one thing to do with thermal efficiency.