The L&M Blog

A Guide to the Different Venting Options for Gas Fireplaces

Since time immemorial people have gathered around the fire to share stories, strengthen bonds and stay warm. The practice of gathering around the indoor fireplace goes back almost as far, to the days when early humans first brought fire into the cave with them, and has continued on to the present day. While many homes in Piedmont, SD still have traditional wood burning fireplaces they simply aren’t practical in every house or every location and so alternatives have been developed to fulfill the primal need for fire. Those alternatives include

Venting Gas Fireplaces
  • Burning fake logs
  • Converting to electric system
  • Converting to a pellet burning system
  • Abandoning the fireplace or
  • Switching to gas

Of all of these alternatives the only one that will give you the look and feel of a traditional wood burning hearth is gas.

Types of Gas Fireplaces

There are three basic types of gas fireplaces for the home. They are:

  • Inserts - A fully self-contained insert is slid into the existing opening and hooked up to gas lines and whatever venting system you’re using.
  • Free standing gas stoves - These have some traditional visual cues but stand away from the wall on their own specially built platform. You’ll sometimes see these in cabins but not so often in urban residences.
  • Built in gas fireplaces - These are created from scratch by the fireplace service company for homes with no chimney.

Inserts are probably the most common form of gas fireplace in Rapid City, SD because they do not require any new construction and they faithfully mimic the appearance of traditional wood burning fireplaces. They are not however without their issues and primary among these is the issue of venting.

The Fireplace Venting Issue

Fireplaces, whether wood burning or gas, produce a lot of heat and fumes that need to be accounted for. This is done by venting. There are 4 different ways homeowners vent gas burning fireplaces today and below we’ll take a close look at them all.

  1. B Vent - The B Vent is typically part of an insert setup. It not only has the traditional look of wood fireplaces it vents like them too, with the heat and fumes being directed up the chimney. So why aren’t all gas fireplaces B Vent fireplaces? For a couple of reasons. First, they can be more expensive to install than other venting methods (especially if you don’t have an opening you can install an insert into and instead use a free standing setup). Second, they are notoriously inefficient when it comes to producing useful heat. In fact some have an efficiency rating of only 20 or 25% which makes them the least efficient type of gas setup you can have. On the upside they produce the most natural looking flame and you typically have some flexibility as to where the vent pipes will run.
  2. Direct Vent - The direct vent system is another that typically uses an insert. Once the insert is in place 2 pipes are set up to provide fuel and exhaust capabilities. The “fuel” pipe draws air in from outside to fuel the flames (instead of from your living room like the B Vent). The exhaust pipe typically runs out the back of the chimney structure rather than all the way out the top. With the Direct Vent system the front of the gas fireplace is sealed off from the home so no air is pulled in from the living areas and no fumes are vented into them. Heat is generated by pulling room temperature air into a space under the stove setup. As this air heats up it rises and is then blown out of vents above the glass front to warm the room. These vents can be closed if the room is getting too hot. The Direct Vent gas stove is typically more efficient than a B Vent meaning it will return more of the heat generated back into the home. While most people use an insert setup for the Direct Vent there are some who will use it with a freestanding gas unit.
  3. Ventless - With this type of setup the name says it all. There are no exhaust vents going through the wall or up the chimney. Air is drawn from the room and heat is returned directly into the room. They can get away with this type of system because the stove burns gas at an incredibly high rate of efficiency and therefore does not generate any harmful fumes. Critics are fond of saying that the risk from the Ventless system is unacceptably high. But the fact remains that there are zero confirmed deaths caused by this type of setup. That’s “0”. So the argument about them being dangerous really doesn’t hold water. Still, if you are nervous about the idea of having a fireplace that vents into the living area you can have the fireplace repair company install a carbon monoxide detector and/or oxygen detector that will shut it down if CO levels climb too high or oxygen levels drop too low. The glory of the ventless system is two-fold. First you can put it just about anywhere you want and second, it will typically do an excellent job heating the living areas of the home.
  4. Power Vent - The Power Vent system has not yet gained widespread acceptance but that doesn’t mean it’s without merit. With the power vent a fan is installed within the vent to boost air flow which allows for much longer vent lengths and configurations than would otherwise be possible. The big plus about this type of venting system is that it allows you to place a freestanding gas unit just about anywhere and make the vents as long and winding as you need them to be. The downside is that running vents a long way through the walls can be expensive.

For more information on the various types of venting used for gas fireplaces call L&M at (605) 343-6406. We’re your fireplace service and fireplace repair specialists in Piedmont, SD and Rapid City, SD.