wood furnace/not enough heat

I am looking for any input concerning my 8yo Newmac oil wood comb furnace. When I use the oil, (which is rare) it heats the house fine. When I heat with wood, it struggles to get the house much over 60 if it is 20 or below outside.
It is a big rambling farmhouse(3500sqft) with r38 wall insulation and mostly newer insulated windows.
The fires that I burn are cranking hot hardwood fires. So hot that you cant get your face too close to the fire box.
That hot fire does not translate into a warm house. I also go through 10 full cords per year (oct to april)
I am pretty good with maintenance, dismantling and cleaning the angled steel chimney (6') that goes to the house chimney 2 to 3 times per year. I also scrape the soot that accumulates around the plenum, and change the air filters yearly. Any suggestions to improve this situation would be appreciated.

try lower speed on fan and have it come on earlier and run longer.

Are you burning on the coal grates or have you installed a floor for wood burning? My wife had one of these in her house years ago and it was very difficult to control. It would burn up a whole firebox of wood in two hours and deliver all the heat all at once and them go cold. The only way to be comfortable was rto add two sticks at a time and add again after they burned.