I think the problem described below could be caused by the grate positioning in the firebox. The gas logs that have been causing me some problems are not positioned as far back in the fireplace
(1-2 inches closer to the front).
I don't think this is causing the pilot to go out, but it could be causing the extra smell/updraft right in front of the fireplace. However, let me know if I'm not on the right track.
Here's some more information that might help...
We have two fireplaces in the house with the exact same set up (Peterson logs, etc.)...same burner, logs, safety pilot, everything.
The one I'm having trouble with seems to smell stronger and the air seems to waft up right in front more than the other one. The smell isn't bad or really strong, but it's kind of like burning kerosene. If I'm standing at the same place in front of both fireplaces, the one that's working fine doesn't have the same smell or 'updraft'.
Does this sound like an issue? I've checked the chimney draft several times and it's fine.
I'm still going to replace the thermocouple, but wanted to run this by you in the meantime.