Combustion fan speed/FR (firing rate)

With the Coal-trol is it better to have the combustion fan on the lowest or highest speed in correlation to how much fuel is burned? If you have it lower you are not burning the coal as fast but it is not getting the stove temperature as hot so in turn might be making the electronics call for more coal??? Am I thinking about this wrong?

As far as I know, there is NO control on the CoalTrol for "Combustion" Fan Speed. it should run 100% full all the time.

Only "Convection" heat Speed is variable and that is proportional to the Feed Rate/temperature requirements. Lower Feed Rate = Lower Convection Fan speed and or NO fan at all.