Problems With Unvented Gas Logs

Artificial Look

• The special clean-burning design of unvented gas logs makes it possible for the fireplace to be used with the damper closed, but, as a result, the fire isn't as hot, with a BTU (heat energy) rating that's about a third of that of vented logs. The fire, consequently, doesn't look as real.

Air Quality

• Because of the changes unvented logs make to the air in the room or house, some states have banned them. A slight odor that emanates from the device, coupled with a reduced level of oxygen in the area, make the environment uncomfortable for people with respiratory issues. This is particularly a problem with new, well-insulated, high-quality homes. Fortunately, unvented fireplaces are equipped with oxygen depletion sensors, which monitor oxygen levels and would automatically shut off the flame if levels dipped too low.

Inconvenience

• Unvented logs come in specific configurations that can't be added to or reorganized. They also don't commonly work with remote controls, wall thermostats and other accessories that can be purchased alongside vented fireplaces. Because they're basically an open flame, unvented fireplaces should be treated with the same respect and precautions as a traditional wood-burning fire. They aren't designed for full-time, whole-home heating, and they shouldn't be left on when unattended. Because of their efficiency, they produce a lot of heat, and objects just above the fire can be warped or otherwise damaged.