A ventless (or vent-free) gas heating product is a heating appliance, such as a fireplace, stove, or log set, designed to operate without a chimney, flue, or vent. These systems can be fueled by either natural gas or propane and are typically used to provide supplemental heat to a home.
Because ventless products do not require a vent or chimney, all of the heat they generate stays inside the home, making them 99.9% energy efficient. This means that nearly all the energy from the fuel is converted into heat, making vent-free products an efficient and cost-effective heating solution. However, they must be used in well-ventilated areas to maintain safe air quality levels.