Unvented gas heater


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Unvented gas heater

Gas-burning space heater that is not vented to the outdoors. Although unvented gas heaters burn very efficiently, indoor air quality experts strongly discourage their use because combustion gases, including high levels of water vapor, are released into the room or building.
References in periodicals archive ?
Vent-free or unvented gas heaters are supplementary heat sources, since they require no vent.