We run our wood fired add-on furnace 24-7 N,D,J,F,M and it usually takes one fill at wake up, one during the day and a load of nice dry oak for the night, and there are enough coals in the morning to start with.
Chimney cleaning, within the next week here, then 6-8 wks apart, depending on what is seen on inspection. There is an old 6" pipe hole down and opposite of where the current smokepipe enters, I use it as an inspection hole with a 1mcp Qbeam, and a really clear mirror, gives me a great look at the buildup(if any at all) on the chimney walls, and the conditon of the smokepipe. I do a looksee from the roof as well, before I sweep it, and after to see the difference. So far, always less than 1/4" of dry, dusty build up, between cleanings, a 12x12 steel brush makes quick work of cleaning, and does a fine job.
Do I worry about our safety when we sleep, no, if I get curious before bed, I just go downstairs with the light/mirror and take a peek.
I also have a device for measuring the flue gas temperature, smoke pipe temperature all along the length of the smoke pipe, lets me know if things are where they should be, 400-600* on the inside.
Now, if I could just cut the 5 or so cords down to 4 or so cords, that would be better yet, but that would probably mean insulating, replace some windows, and so on, but the 3ksq/ft house sits at 66-72* throughout most of the winter as it is.