Why is the EnerGuide FE rating lower than the SS or AFUE ratings?
All fireplaces are subject to some energy losses. Some of the heat escapes up the chimney (stack losses), and some is lost to the house from the appliance’s hidden surfaces (casing losses). A pilot light running continuously can account for a significant portion of a fireplace’s annual fuel consumption, all the while producing little useful heat. Because P.4 test methodology is based on how fireplaces are typically used in the home, the EnerGuide FE rating for a particular make and model of fireplace will often be lower than the SS or AFUE ratings. The FE rating is a reliable measurement of fireplace efficiency based on how it operates in a Canadian home.
