Learn why a vent-free gas fireplace is not a good idea. Find out why you may be in danger of carbon monoxide poisoning if you use a vent-free gas fireplace.
LESLIE: Alright, now we’ve got Rick in Texas who’s got a question about propane. What’s going on?
RICK: Well, I’ve got a propane tank in our house and I want to use some vent-free fireplace logs and I was wondering if there’s any danger; if I need to worry anything about like carbon monoxide  if I have my vent closed on my chimney and I run these vent-free propane logs.
TOM: Absolutely. Now, you say a vent-free propane log. I’m not following you on that. This is a ceramic log for a fireplace that’s designed to work with a gas fireplace ? Is that what you’re saying?
TOM: And when you say vent-free, are you telling me that the log is manufactured to be so small that you don’t have to vent it?
RICK: That’s correct.
TOM: Well, look. I don’t like unvented fireplaces ; never have for a bunch of reasons, one of which is carbon monoxide and the second of which is moisture. When you burn natural gas or propane the offgas on that is 80 percent water vapor. So now you’re putting acidic water vapor into the house air. Even if it is so low that it doesn’t have carbon monoxide in it, it’s still a bad idea.
TOM: So I would recommend against it.
RICK: Alright, that makes sense. Thank you.
TOM: You’re welcome, Rick. Thanks so much for calling us at 888-MONEY-PIT.