Gas Fireplace Venting: Direct Vent or Ventless

The gas fireplaces use a few different types of venting systems. One is the B-vent or the natural vent, another is the ventless gas fireplaces and also the gas fireplace direct vent. While all of these venting systems are very different they do have one thing in common. They allow for gas fireplaces to be installed with out the chimney that is used for the wood burning fireplaces.

The B-vent or the natural will use the air inside the room to draw in for the combustion process. The by products of the combustion is then expelled up a vent that terminates about the roof line, sort of like a furnace. While this technique is the most decorative, this system does take a little away from the efficiencies of the gas fireplaces. This option will cost less then the direct vent system.

The ventless gas fireplaces operate without the use of any venting system at all. The air to be used for the combustion process is pulled in from that room, is used, then all of the by products are blown back into the same room. This system uses a oxygen monitoring system called an Oxygen Depletion System, also known as the ODS. This will shut the gas fireplaces off if the oxygen in the room drops 2 %.
Not every manufacture of gas fireplaces will produce this type of gas heater. A few states will not allow the use of these units, and a few states require a permit to use them.. While most states have no opinion either way. Be sure to check your local state codes before purchase.

The gas fireplaces direct vent uses a coaxial pipe, a two in one pipe. The smaller of the pipes or the inside of the pipe will be the one to carry the by products out. The outside of the pipe will bring fresh air to the inside. The fresh air is also heated by the warmer by products and this makes for a more efficient system. This vent can be ran horizontally through the wall or vertically through the roof.

The gas fireplaces will run off of natural gas or propane gas fireplaces. If you live in or close to a city, natural gas is piped into the house through a network of gas lines and a monthly statement will be sent out. If you live outside a city you may have to use the propane gas. A storage tank will be set up on your property. As the gas is used and the tank is low on propane, a gas company will come to refill the propane tank. Depending on the size of the tank and how much you use will gas fireplaces will depend how often the tank will have to be refilled.