Am ending my week and a 1/2 vacation, (since Thanksgiving), and have gotten to experience coal burning for 5 days straight W/O letting my stove go out.I have a diary of all my actions, adjustments, and findings, and have come to this conclusion. I've spent probably more time than needed tending to this stove, but as mentioned B4, I'm still in the experimenting stages, for what's best for me.
My house has never been so warm in the winter, and the temps outside were in the 20s to mid 30s daytime high. With the combination of the intake adjustment knob, and the MPD, I find I do have some control of the burn rate. With this stove, (taking air from below the grates), the most dominant way of "heating up" the coals when they start to cool down, is by cleaning the grates. Which tends to need it roughly every 2-3 hrs. It will burn approx 7-8 hrs before becoming "extinct", or un-lightable, (I imagine), but if caught with-in 5-6 hrs, the coal bed can be saved. the longest burn I've been able to acquire, (so far), using pea coal, has been done with my MPD closed between 45-60*, (doesn't appear to be "too" sensitive), and my intake knob set approx. a little less than 1.(Altho the reference dial may be out of adjustment). The amount of coal burned for these almost 5 complete days is about 7 bags or a little less than 300LBs. At a little less than $50, my cost here, compared to the cost of a gallon of oil, I'm sure that would equate to more than a 40% savings, in my application.
It has been a bit labor intensive, and still learning how to keep the ash dust to a minimum when cleaning the grates and tray, and would like to be able to see a tad more than 5-6 hr sleep nite, but all in all, I think the benefits will outweigh the negatives. (At least for now). Once again, I appreciate everyones help while I transform my "greenness", to something a little less annoying. Thanx.