Gogarty wrote:

The coal won't keep burning without the forced draft and the charcoal. The
firebox is pretty small. The CO monitor is also close to hand and active.
We are not running a sealed room here -- lots of fresh air coming in and a
bulkhead fan to circuilate the warmed air.

I know you are no dummy, but there inherent problems/dangers with
forced draught & coal, some of which lead to induced draught operation
in marine boilers. Doesn't take much of a gas leak to spoil your day.
Another F/D issue is higher explosion potential. Much of this (and the
rest) is long forgotten.

Burning coal today is often problematic as you describe (i.e, both
draught requirements & co-fuels needed). Coal commonly available today
isn't quite what it was in quality when it was a major home heating
fuel & very competitively marketed, nor are typical flues as tall or
grates as well designed for it. You'll find a higher percentage of
unburned fuel & clinker after firing today's coal in today's
appliances. It's also pretty expensive now, & none if its mess has
gone away.

You are right that charcoal briquettes are usually crap in a stove.
Coke would be much better if obtainable.

We are especially mindful of the hazards of CO since two people died at our
marina two years ago when they left the engine running to run the
airconditioner.

Cool way to die (not).

BTW, what is the present safety concensus about keeping E/R exhaust
running to insure negative pressure during motoring on yachts?