Direct Vent Gas Fireplace draft (my fireplace, heating, chimney, upstairs)

[NNCSavage]

I just bought a 5yr old home with a Heat and Glow OAK-6000TR direct vent gas fireplace.
Whenever there is wind the draft is horrible but even without it's cold and I'm sure it's not helping my heating bill.
The vent is straight back and a rather short run which I'm sure doesn't help.
I was looking at this thread from last year and this is exactly my problem as well:
https://www.city-data.com/forum/house...rect-vent.html
As well as the one recently bumped that didn't seem to have any solutions.
I was about to try the duct tape and plastic bag method that wheelsup used in the first thread but figured I'd ask first to see if there were any other options.

I've checked the manual here and online and it mentions something that might be a shutter valve or air control. I believe it claims there is a lever to the right of the gas/start assembly but I do not see anything other than those 2.

I've also tried popping the clamps on the gas front to remove it to see if I can determine where the draft is coming from but after popping all 4 i cannot seem to get the panel off.

Other than starting them up I am a complete rookie at this. Any ideas or pointers? I can try to get some pics up if that would help.

Thanks,
Jim

[LAB6120]

I have the same issue with my fireplace. There is a vent that you can close that lets the smoke out the chimney-if you look to the front of the fireplace you should see a metal latch that closes that vent. However, I still had a draft after doing this, so I checked outside and there is also a vent on the side of the chimney that lets air in-you can cover this up with plastic and duct tape, not sure if they sell something pre-built for this vent. This solved my downstairs fireplace but I could not reach the upstairs vent, so I just taped it off with plastic. Just remember to open these vents if you plan on using the fireplace.

[AnotherBravesFan]

Chimney top is capped off, but we had a terrible draft with no apparent way to stop it, so I cut some foam board to size, covered it with flannel and used double-sided tape to affix it to the front of the firebox. Not perfect, but it's helping. I think the long-term solution is to replace the fireplace or eliminate it. DH scared to use a direct vent FP, so it's only decorative at this point anyway.

[NNCSavage]

It's direct vent maybe 20 inches straight out the back, perhaps less. No Chimney at all.

[NNCSavage]

I jammed some old sheets around the top and bottom on the inside and the draft is significantly less but it's not really my preferred solution.