How Does a Vent-Free Fireplace Work?

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No Chimney Required

A vent-free fireplace requires no chimney or outside ventilation system. Any heat produced stays inside. Instead of bringing in air from the outside and exhausting the combustible byproducts outside as a vented fireplace would do, a vent-free heating system burns air that is already inside, thus requiring no vent. The vent-free fireplace operates on natural or propane gas, just as might your oven, dryer or gas range, and most models do not require electricity to run. Natural gas is clean burning, without a lot of fumes and emissions, so the amounts of carbon monoxide emitted are very small and within safety limitations set down by the EPA.



Vent-free fireplaces contain an Oxygen Depletion Safety Pilot (ODS), which cuts off the flame in the fireplace when the oxygen levels in the room grow too low. This feature in the vent-free fireplace is excellent for safety. You can also purchase vent-free logs specifically designed to work in your fireplace. These logs emit a blue flame, rather than the orange flame of a traditional burning log. Also, the damper in the fireplace need not stay open, while a direct vent fireplace requires an open damper. This type of fireplace is often found in bedrooms, bathrooms or game rooms with no chimney design. Before installing such a model, check with your building codes for acceptable BTU limits in these rooms and for coding regulations in your area.



Compared to more expensive vented units, vent-free fireplaces typically run 65 to 70 percent of the cost. The installation costs, without the need to run outside ventilation lines or chimneys, is much lower than the alternative. Vent-free heaters are said to be 99 percent efficient in burning fuel, much higher when compared to the vented kind, thus saving the homeowner on fuel costs. Finally, vent-free fireplaces allow you a sense of flexibility; they can be installed in virtually any room in the house where there is a gas line. While not for everyone, the vent-free fireplace is a safe and economical option, costing only a few cents per hour.