Vented Gas Logs

How can I tell if gaslogs are the vented or non-vented type by visually inspecting them? I’m talking about the situation where there are gaslogs in a firepalce. I like to recomend that a stop be placed on the damper handle to keep the damper open.

Vent free gas logs will be listed as such but if there is a damper, I’m going to recommend it be locked open or removed for safety regardless.


Vent free gas logs!!!

Do they make such a thing? Never saw one.

I always thought that anything that burns needs to be vented, unless of course it is the size of a candle. ha. ha.

I agree with you on the damper.

Please explain Larry.

Same question I asked Larry Marcel. Please explain.


I think I beat you by about a minute to the punch. ha. ha.

9/21/07, 7:01 PM

Marcel :wink:

There is no need to vent a vent free log or appliance if they are permitted by local jurisdiction and the manufacturer’s instructions are followed.

I agree with that also, but do they make such a thing?

Still waiting for Larry’s explanation.

Marcel :slight_smile: :slight_smile:

Yes they do.

Larry, is this what you are talking about?

I thought you were talking about imittation logs. :slight_smile:

Where Can Unvented Gas Logs Be Installed?

Unvented gas logs can be housed in a masonry fireplace or in special fireboxes made to resemble a hearth.
If Your Gas Logs Create Moisture

Water is another byproduct of combustion. If you have vented gas logs, most of the moisture escapes out the vent, but when you use unvented gas logs the extra moisture enters your home. That can be a plus for many homes during dry winter months, but if your home is tightly insulated, or you have a humidifier, the excess moisture might show up as condensation on cold windows.

Gas Log Safety

  • Unvented gas logs generate a lot of heat. Keep combustibles away from the fireplace.
  • Always leave the fireplace doors open during use.
  • Only burn the gas logs for a few hours at a time. Never go to sleep and leave unvented gas logs burning.
  • Open a window slightly while the gas logs are burning, to let fresh air enter the room.
  • Bigger is not always better. For best air quality, the gas fireplace unit you install should be approved for the size of the room it will be used in.
  • Unvented gas logs are not legal in all areas, so check your local building codes before buying a gas appliance.
    *]Always follow the manufacturer’s instructions when using any type of fuel-burning appliance.
    Marcel :slight_smile:

If there is a damper then they installed the logs in a fireplace that was designed for venting. Vent free gas logs need to have the air intake cleaned regularly to remain 99.9 % clean burning. Otherwise they should shut off automatically. But they are not designed with a damper. So, if the fireplace was modified to accept the vent free it doesn’t need a damper…so I say remove it or lock it open as a precaution.

Removing the damper or locking it open defeats the the redeeming quality of the vent free log which is it’s near 100% efficiency. :shock:

That may be true but I’m in the safety business first and then the client can decide if they prefer efficiency…I guess after having one and cats, I saw how quickly the air intake plugged up and my CO detector would go off until I cleaned it and I got gun shy.

PS: It worked great the first few months then not so good.

Larry, you have me confused;

If I were to use vent free logs in my fireplace that I have now, which I am looking into to make happen, why would I remove my damper if it is vent free?

It gets cold in Maine, and if I am not using the fireplace, my heat would just escape up the chimney.
Would it not be better for me to stick to a vented gas insert?

Marcel :slight_smile: :smiley:

I understabd what you’re saying Marcel but after having one in my own house I was not impressed…maybe the newer designs are better.

That’s why they are equipped with an ODS(Oxygen Depletion Sensor)
I have had a wall hung unit for about 10 years with little problem other than routine cleaning.:smiley:

Apparently mine was letting in enough CO to set the alarm off before shutting itself off due to lack of oxygen…it scared me off.

Thanks Larry;

I guess this is a subject of further learning and exploring for me.

Marcel :slight_smile: :slight_smile:

I have checked mine repeatedly with my Monoxor and I don’t get CO measurements that are of concern.:slight_smile:

My mother has used one as a supplemental heat source for years without a problem. CO alarm never goes off. Damper remains shut, as do the doors and windows in winter.