Nat gas fireplace: odor, soot on glass

Hi folks-
Here's another post about the house my family recently moved into...
The natural gas fireplace seems to be out of adjustment. Upon flipping the switch, the fireplace lights and we get strong yellow flames, but it generates a significant amount of odor. The odor isn't "leaking gas smell" but is "burned something smell." Also, after about 4 hours of use since we've moved in, the front glass of the fireplace is now coated with a significant amount of carbon, making it hard to see the gas logs.
The fireplace is original to the house, built in 2000.
We don't have a manual but I might be able to find a label if I poke around inside... Or is this a job for a pro? I have no experience with gas fireplaces.
Marc
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Hire a pro. Yellow flames and a sooted up windows mean carbon monoxide. This will kill you if not corrected. It almost killed this family.
http://www.news10.net/storyfull2.aspx?storyid 324
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Please not the following as a possible reference to your strong yellow flame comments:
Vented gas logs primarily produce a yellow flame which is attractive and natural. However, these yellow flames are not as hot or efficient as a typical blue gas flame. Yellow flames also contain soot and the use of vented gas logs does not eliminate the need for chimney cleaning. Since vented gas logs produce soot, a little smoke and possibly carbon monoxide (just like a real wood fire) your fireplace damper must be fully open when using your vented gas logs. Additionally, since vented gas logs produce soot the use of blowers is not recommended as we have seen many cases where soot was blown into the house by the blower. Manufacturers require that the damper be blocked open and the city inspector checks this during the inspection. Since the damper is always open, glass fireplace enclosures are recommended for fireplaces with vented gas logs. Glass doors should always be fully open when the gas logs are burned. Vented gas logs should only be installed in operable wood burning fireplaces. If your fireplace doesn’t draw well when burning wood there is no guarantee that it will work with a gas log. In short, a gas log is not a cure-all for an ailing fireplace. When installing gas logs in a factory-built fireplace check to see that the fireplace is approved for the installation of vented gas logs (most are).
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snipped-for-privacy@nowhere.com says...

Folks-
I called the original installer (based on paperwork in the house)and explained the problem. They said that based on the description of the problem, the unit has probably never been burned in and the odor/soot are probably normal for the first 20 hours or so of use. They said to check the venting and as long as the vent was clear, the best thing was to run flames for a while to see if it clears up.
Tonight I opened it up, with the manual in front of me. Got a blast of cold air in through the vent with the glass off, so I know the vent isn't blocked (the vent just goes straight out the side of the house, probably not more than four feet total combined up-and-out, and no overgrown bushes blocking it).
The ember material was somewhat excessively covering the burner, so I moved it to better match the drawing in the manual.
Put the glass back on and started it up. Flames were bluer than before, but after about 20 minutes were looking relatively yellow again, with the odor coming back.
I adjusted the flame down a bit with the hi-low adjustment. It's venting to the outside, and I can see there is a draw of air toward the unit, so I'm not too worried about CO etc..
For now I'll follow the advice of the installer, though one point does concern me: the manual says there are "air shutters" that can be adjusted. I haven't found any in the manual, so I'm not sure where they would be. Any ideas? It's a Martin Industries 5500 series direct vent system.
Marc
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Marc_G wrote:

Hi, The shutter is at the bottom where the gas supply pipe is. My guess is it is not adjusted properly. Need a screw driver too loosen the shutter and swievel back and forth for proper flame color(blue). Open the flap at the bottom of FP and follow the pipe>>>>up to the fire box>>>>>to the burner; along there you should see shutter. I have 3 FPs in my house and front glass needs cleaning once a year or so. When the house was new, there was slight smell of paint curing but now no smell of anything. Just nice flame to look at and warm heat. Ours are equipped with fan on thermostat. Good luck, Tony
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Thanks Tony!
I'll look for those shutters. By the time I started looking last night, the thing was very hot from running, and I didn't want to get burned. Today, with it nice and cool, I'll vacuum out the dust/cobwebs, follow the pipes as you said, and see about adjusting those shutters.
Marc
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snipped-for-privacy@nowhere.com says...

Thanks again Tony. I did indeed find the air shutter which was an adjustable collar around the gas tube on the burner element, before the actual burner holes. It was fully closed. I opened it about one third of the way, and reassembled.
The flames are now completely blue when it first starts up, but it settles down to pretty yellow flames after about 10-15 minutes of use. Not sure why the color of the flames varies as it heats up; presumably something to do with the logs.
We've run it for about 5 hours since the adjustment and no more soot on the glass, and very little odor (not no odor at all, though... maybe after some time it will go away).
Problem solved.
Marc
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