After almost 4 years of using a Mark III, I am starting to realize that the
fire needs a little help once in a while and when I start to see some
areas towards the front of the firebox that aren't hot and bright like
the rest, I take a metal angled rod, and sweep down along the top
of that front shaker grate, back and forth. I usually pull up a couple
chunks of old burnt coal that don't drop thru the grates. This will also
drop a bunch of ash thru that front grate and then I'll pull a few bits
of good hot burning coal towards that low spot, fill the firebox as normal,
and it's all set for another few days. I don't have to do it every day,
but maybe every 5 or 6 days.
If you are getting a lot of the firebox that isn't really hot and red, you may
need to try shaking more vigorously to really open up the airways up into
the coal from underneath. I doubt anything with your baro is causing any
issues,, if the coal can't breath, it can't burn efficiently.
when is this winter going to end! brrrrrrrrrrrrrrr