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).