What is AFUE?
As we have talked about many times on this website, fireplace efficiency is a key metric to choosing the right indoor fireplace for your space. When you are trying to figure out the efficiency of your fireplace two measurements can be used. BTU's, or the British Thermal Unit, is a common measurement that we discuss more in-depth in another article. Today, we will be talking about AFUE, or Annual Fuel Utilization Efficiency.
AFUE measures how efficiently your fireplace turns fuel into heat. This is measured by what percentage of the heat is lost up the chimney and how much of it heats a room. Because open faced wood fireplaces and open gas fireplaces are very inefficient and vent free fireplaces don't use a chimney system at all, AFUE isn't a helpful measurement to consider. Typically, AFUE is only needed when considering the heat efficiency of a direct vent fireplace.
It can be hard to balance all the measurements and ratings and come out with clear understanding of what you need, instead of a headache. Though, unless you are considering a direct vent appliance, the manufacturers data plate on your fireplace likely wont mention AFUE. So, that is one less thing to think about if you are looking for a vent free fireplace or open wood fireplace
