Fireplace inserts are like wood stoves that are specially designed to fit a brickwork fireplace’s firebox. They are used to transform masonry fireplaces, which could be polluting and inefficient, into effective systems for heating. A fireplace insert has a firebox, which is surrounded by a shell made out of steel. The air inside the room would flow into the shell and firebox to be warmed. The outer shell would make sure that majority of the heat coming from the firebox will be distributed into the room rather than released to the masonry structure. The space between the fireplace opening and insert body is covered with a decorative faceplate.
Back when the first fireplace inserts were installed in the 1980’s, they were considered to be inefficient, unsafe and costly to maintain. Most of the inserts back then were not directly connected to the chimney of the fireplace and a lot of the older inserts permitted the exhaust gases to come out the flue collar to go up the chimney.
Eventually, a short liner made from stainless steel was installed in the chimney of the old fireplace. This short liner was referred to as a direct connect, however there was no actual connection to fireplace chimney’s base. The inserts that were installed through this method emitted a lot of smoke, were difficult to light and expensive to maintain, as the insert needs to be removed first to be able to clean the chimney.
In 1991, the Canadian code for wood burning installation required for a stainless steel liner to be installed from the flue collar all the way to the chimney’s top. The code also allowed modification to be made to the fireplace so that the installer would be able to make a clear route for the liner to pass through the original fireplace’s throat and smoke chamber. Because of this, a good installation of a fireplace insert is permanent.
This development in the insert installations’ design was able to improve their performance that if you would be checking out the best fireplace inserts in the market today, you will find out that they are nearly as efficient as the operation of free standing woodstoves. So if you have already installed an insert in your masonry fireplace, adding a stainless steel liner will definitely enhance performance.
This site features information on inserts for the three main types of fireplaces; electric, wood burning and gas.