How Does A Ventless Gas Fireplace Work?

If you want to minimize the high cost of installing the exhaust flue or vent of your fireplace, you can go for the ventless fireplace. But question may appear in your head that, how does a ventless gas fireplace work? Is it safe to use?

The ventless one comes with a regulator that produces a mixture of air and gas where the gas gets to burn cleanly. They are connected to a gas or propane line, and the oxygen from indoor air enters through the bottom of the fireplace.

In this article, I will have a detailed look over ventless fireplace. I’ll also discuss the differences between the vented and the ventless fireplaces.

What Is a Ventless Gas Fireplace?

A Ventless Gas fireplace is also known as a vent-free or unvented fireplace. These fireplaces are designed to provide more efficiency than the vented ones.

They pipe natural gas or liquid propane (LP) into a gas burning unit mounted in the fireplace. After ignition, the flames reach up through the gaps in artificial ceramic fiber logs. They produce fewer fumes and don’t need any flue and chimney. That’s why they are called ventless.

However, there can be legal bindings in certain states in terms of using ventless fireplaces. For instance, California and some other states doesn’t allow them.

How Does A Ventless Gas Fireplace Work?

Ventless fireplaceshave a U-shaped construction. They rely on indoor air for combustion. They are connected to a gas or propane line, and the oxygen from indoor air enters through the bottom of the fireplace.

A regulator helps create a perfect mixture of air and gas to burn the gas cleanly. The burners leave almost no exhaust behind. That’s why these fireplaces produce a negligible amount of fume.

There are incombustible artificial logs with holes by which the flames pass through. Ventless fireplace emits a very low amount of exhaust in the room. As the gas gets burnt cleanly, it offers almost 100% efficiency. 

Are Ventless Fireplaces Safe? 

Well, this is still a controversial issue. While it’s true that a ventless gas fireplace emits some noxious gas into the room it is operating, it has some features to keep it minimal. They also have to meet certain essential safety criteria. 

Although ventless fireplaces are designed to create no exhaust, they emit some of the by-products created from the burning of gas. It includes noxious gas like nitrous dioxide and carbon mono oxide.

Moreover, they use oxygen from the indoor air. If your room doesn’t have a good ventilation system, the air quality can drop severely and create a severe health risk. 

But today’s models come with a CO detector and oxygen depletion sensors (OSD) to monitor the air quality of the room.

When the amount of oxygen drops to an unhealthy extent, the OSD automatically shuts the fireplace off. The CO detector does the same when they detect extra carbon monoxide.

Usually, these safety devices automatically shut off the fireplace if the oxygen level falls below 18% and if the carbon monoxide level rises above 25 parts per million, which is the suggested level for indoor air quality by the U.S Environmental Protect Agency. 

Still, it is recommended to have at least one window in the room where you install the fireplace. Also, try to use them in regular intervals. Don’t use them for more than one hour in one interval. It will help remove the unhealthy air from your room.

All that being said, if you follow the recommendations of the manufacturer and install the fireplace properly, a ventless gas fireplace is safe to use. 

Ventless vs Vented Fireplace

Gas fireplaces come in two variants – A vented and a ventless fireplace. The vented fireplaces use two vents.

The intake vent draws the fresh air into the fireplace, and the exhaust vent removes the fumes produced from the burning process. They cost somewhere between $3000 to $8000 depending on the quality. 

On the other hand, a ventless fireplace requires no chimney. They are designed to burn the gas without any exhaust and produce a very less amount of fumes. These fireplaces cost $1000 to $5000.

Ventless gas fireplaces don’t require any vent or chimney. Hence, installing them is also easier than their counterparts and costs less than that of the vented ones. 

They can produce more heat per BTU as they burn the gas properly. They provide 99.9% efficiency. So, no gas gets wasted here.

The room also gets heated faster. Safety devices like OSD and CO detectors turn the fireplace off when the air quality becomes unsafe. 

These fireplaces also offer great convenience as they can easily be operated by remote and provide heat during power outages.

Maintenance of Ventless Fireplace

It is always recommended to contact a gas or plumbing contractor for the professional installation. The heating capacity should not exceed the range for an appropriate room size mentioned by the manufacturers.

Ventless fireplaces require at least annual cleaning of the log set and other exposed components.

The oxygen and carbon monoxide monitors of gas and propane products should be checked and adjusted annually for optimum performance.

The logs should be inserted and positioned correctly. The fireplace sensor should be free of dust and other particles to offer optimum operation.

As the fireplace components and surrounding areas retain heat, you need to avoid touching hot areas with your bare hands.

Turn off the unit and consult a professional if you notice unusual noises or odors coming from the fireplace.

Final words

Do you know now how does a ventless gas fireplace work? Ventless fireplaces heat your room faster and offer efficiency. However, they have their downsides too. So it’s up to you whether you want efficiency or a genuine look at the flames.