Hi 5052, you don't use the furnace fan, you use the distribution fan on the Harman. Just like you let the hot air mosey on out the hot air duct, put a slight suction on the cold air return the same way. You will be amazed at how much of a difference it will make.
Right now you are pulling cold air off the basement floor, the coldest air in the house, and running it through the stove. If you reheat air pulled from the upstairs rooms instead, you will get much more effecient use of the stove. This is what forced air furnaces do, they have sealed ducts on the furnace, only heating recirculated air.
One forum member had cut holes, added ducts, added duct fans etc, and still was unhappy with the heat distribution. Then he added a simple floor register in a distant part of the house, hooked this to the inlet of the distribution fan of his stove, and imediately had much more heat and more even distribution. He used inexpensive 4" dryer vent tubing!! Nothing fancy!1 The loop-effect is what works.
Hope this makes sense.