Gas Logs - Vent Free

When people hear about vent free gas logs, their reactions can be mixed. On the one hand, it sounds as though such logs are simplicity itself. If you don't have to worry about venting, you can install them easily, anywhere it's safe to have a fire. On the other hand, doesn't "vent free" just mean that the logs are venting gases and fumes into the home rather than outside?

Well, yes. A vent free gas log does vent its fumes into the home. It also draws air from the home to fuel combustion. That means vent free gas logs need to be and are designed to be very low in emissions. They are tested and rated as safe for indoor use. Still, at least some states feel you are right to be concerned. Vent free gas logs are not legal everywhere. Your local home store may not carry them for this reason. Don't send off for them by mail unless you're sure you're allowed to own and operate them.

If you do decide to install vent free gas logs, you'll want to take some precautions to make sure that they are working safely. Even a log with tightly controlled emissions and a clean, clean burn is still going to produce some carbon monoxide (CO). The problem with CO, of course, is that your blood will bind to it instead of to oxygen, depriving you of air even though you're breathing plenty of air in along with the CO. Under normal circumstances, a gas log won't produce nearly enough CO to pose a health risk. But you want to be sure.

For starters, all vent free gas logs are equipped with an Oxygen Depletion Sensor. This sensor turns off the gas before the levels of CO in the room become dangerous. As a second line of defense, it's a good idea to install a carbon monoxide detector in the home. This is an inexpensive device that will alert you if the CO levels are becoming dangerous.

Another problem you may encounter with vent free gas logs is moisture. It may not seem intuitive, but fire produces water. Actually, it produces hydrogen gas, among other things. That hydrogen binds to the oxygen in the air, producing water. With a vented log, that moisture production takes place outside. A vent free log produces moisture inside. This can be fine within limits, even helpful during dry winters. But if you start to see condensation on your windows, it may be too much. The moisture can lead to mold or mildew in the summer months. Opening a window a crack, especially upstairs, can help.

Finally, if you get a vent free log, keep these safety tips in mind:

Never leave the log unattended. Especially do not go to sleep with the vent free log still burning. Many manufacturers recommend you only operate them for a few hours at a time.

Always leave the fireplace doors open during use. The logs require air for combustion.

Remember that these logs generate a lot of heat. Keep a safe distance and make sure nothing flammable is too near them.

Don't go for the biggest log you can find. Get the one rated for your size room.