When energy efficient appliances are spoken of, rarely is a gas fireplace mentioned. Gas fireplaces, in the past have been costly to run, and did not provide much, if any heat. In more recent years, great strides have been made with gas burning fireplaces, and many fireplace manufacturers have developed sealed gas fireplace units. The major benefit of these units is that the unit can produce a lot of heat, up to 25,000 BTU/hr on some units, which is enough to heat a large portion of a home with a blower fan. These units can be vented directly out an exterior wall making the installation fairly simple. However, the issue of cost to run these units remains something that many people still have a hard time grasping, even with the improved energy efficiency of these vented units. But if you want a new fireplace in the middle of a room, it has typically been too costly or simply not feasible to install the necessary venting for a gas burning fireplace. This is no longer true with the invention of vent free gas fireplaces.
Vent Free Fireplaces
Vent free fireplaces burn natural gas or propane fuel like any other gas fireplace. The difference is how the vent free fireplace burns the fuel. While there are many units of vented gas fireplaces available that offer 86%-90% efficiency, vent free fireplaces offer 99.9% efficiency. This is the only reason that these units are allowed to be unvented is because of the almost perfect combustion.
How Combustion Works
In order to have combustion, you need fuel, air, and heat. Of course you need enough of all of these to make something burn. When burning anything, there is a certain amount of material that does not burn. This is where you get smoke, carbon monoxide, and soot. These waste products of incomplete combustion do not build up in a ventless unit because there is virtually no wasted gas. All but .01% of the gas fuel coming from the inlet is burned with the most minimal amount of smoke, carbon monoxide, and produced. So little that it is virtually undetectable.
Because of the complete combustion that occurs from the ventless units, there is significantly more heat that can be produced. This mean that a small unit will put out plenty of heat in a space without dominating it.
Ventless gas fireplaces are an energy efficient way to enjoy the warmth of a fire, while being environmentally conscience and not producing soot, carbon, or indoor air pollution.