Should You Open The Flue On A Gas Fireplace? – The Pros and Cons

Last Updated on October 21, 2022 by Jason Nguyen

There is a lot of debate about whether or not you should open the flue on a gas fireplace. Some people say it’s necessary in order to prevent the buildup of carbon monoxide, while others say that it’s not necessary and can actually be harmful. So, what’s the truth? In this blog post, we will discuss the pros and cons of opening the flue on a gas fireplace and help you decide what is best for your home.

Should you open the flue on a gas fireplace?

flue on gas fireplace

The answer is: it depends. If your gas fireplace is vented, then you should open the flue when using it. This will help to prevent carbon monoxide from building up in your home.

If your gas fireplace is unvented, then you should not open the flue. This is because unvented fireplaces burn fuel more efficiently and don’t produce as much carbon monoxide.

Pros and cons of opening the flue on a gas fireplace

There are a few pros and cons to opening the flue on a gas fireplace.

One pro is that it allows fresh air into the room, which can help circulate the heat better.

A con is that it can also let cold air in, which can make the room colder overall.

Another pro is that it can help prevent carbon monoxide buildup.

A con is that it can also let smoke and fumes into the room.

What Is A Gas Fireplace Flue?

A gas fireplace flue is a duct that helps to ventilate and circulate the hot air produced by your gas fireplace. The flue also helps to keep the fire contained within the fireplace, and prevents any dangerous gases from entering your home.

Most gas fireplaces have a metal flue that runs up the chimney, but there are also some that have a plastic flue. Either type of flue will need to be regularly cleaned in order to prevent any build-up of soot or debris.

Should gas fireplace flue be open or closed?

There is no definitive answer, as it depends on a few factors. If your gas fireplace is vented, then you should keep the flue open when in use.

This will allow any harmful gases to be vented outside. However, if your gas fireplace is unvented, then you should keep the flue closed when in use. This will help to prevent any harmful gases from entering your home.

Is it safe to close the flue on a gas fireplace?

The answer is yes, it is safe to close the flue on a gas fireplace. However, there are a few things you should keep in mind before doing so.

First, make sure that the fire is completely out and that the ashes have been removed.

Secondly, close the damper all the way so that no air can enter the chimney.

Finally, close the gas valve to the fireplace. Doing all of these things will ensure that your fireplace is safe and ready to be used again.

Gas fireplace flue requirements.

All gas fireplaces must have a properly functioning flue. The flue serves two purposes: to remove combustion by-products from the home and to provide fresh air for the fireplace to function properly.

A gas fireplace flue must be:

  • Made of non-combustible material
  • At least 12 inches in diameter
  • Installed according to the manufacturer’s instructions

Do All Gas Fireplaces Have A Flue?

No, not all gas fireplaces have a flue. Some models are designed to be placed against an exterior wall and vented directly through the wall. These types of fireplaces are usually more expensive than those that require a flue.

Do Gas Fireplaces Need A Chimney?

modern gas fireplace

A gas fireplace doesn’t require a chimney in the traditional sense. The gas is vented directly to the outside through a pipe or vent. This type of installation is called direct venting, and it’s the most popular way to install a gas fireplace.

There are two types of direct-vent fireplaces: natural draft and power vent. A natural draft fireplace uses the chimney effect to draw air through the fire and up the flue. A power vent fireplace has a fan that pushes air through the fire and out the vent.

Do gas fireplaces have a damper?

No, gas fireplaces do not have a damper. The reason for this is that gas fireplaces are sealed units that are designed to be safe and efficient. There is no need for a damper with a gas fireplace because the unit does not draw air from the room in which it is located.

Additionally, gas fireplaces come with a glass front that serves as a barrier between the fire and the room.

This glass front also prevents air from entering the fireplace and allows the fire to be properly contained. For these reasons, gas fireplaces do not require a damper and are actually safer without one.

How to open the flue on a gas fireplace

If your gas fireplace has a flue, you’ll need to open it before lighting the fire. The flue is a metal or ceramic pipe that goes up the chimney and allows smoke and fumes to escape.

To open the flue, start by sitting in front of the fireplace and looking up at the chimney. You should see a lever or knob near the top of the chimney. This is the flue damper. Reach up and grab the lever or knob, and then pull it down toward you.

You should hear a click as the flue opens. If you don’t, try tugging on the lever or knob to make sure it’s fully open. Once the flue is open, you’re ready to light your fireplace.

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If you have a gas fireplace, you should definitely open the flue before igniting the fire. This will help to ensure that the fumes from the fire are properly ventilated and do not build up in your home. Additionally, opening the flue will help to keep your home warmer since hot air rises. So, if you want to stay cozy and safe this winter, be sure to open the flue on your gas fireplace! Thanks for reading!