Jotul lists this stove as 35,000 btus per hour and recommends it for heating up to 1000 square feet. Clearly it's too small for your needs. Perhaps the place you bought it used only the 900 square foot first floor in its calculations (or was particularly eager to unload this model).
Jotuls are excellent stoves with models that put out much more heat than the Nordic. Other quality brands are available with greater heating capacity. An invaluable internet woodstove resource is www.hearth.com. You can find a wealth of information here about stoves with extensive customer reviews.

Thank you - I will check out that website. I also called another fireplace store and they said I would need an F400. They, like you, thought that the other store might have wanted to unload the Nordic. I'm going to try to sell this one and get the new one for the fall (from the new store, of course!).

I have a Keystoker Automatic Stoker Stove 105,000BTU. I've had it for 1.5yrs.

I have it in my finished family room in the basement. I use it to heat both my first floor(1200 square feet) and my finished basement(700 square feet).

This particular stove has no problem at all keeping both floors of my house at a cozy 75 degrees.

I chose this stove because of the optional 6-inch top convection air vent. The stove has a blower which blows hot air out the front of the stove, but also has a 6 inch top vent that blows air out the top. I have 6 inch duct work hooked to the top vent, and vented to a register directly above the stove. Hot air blows 50/50 out the vents, but you can close either off to get 100 out of either vent.

My only complaint is this: with my thermostat on the first floor and set at 74, the temp will rise and fall between 73 and 76. Downstairs, on the other hand, the temp will rise and fall between 65 and 80. It was a bad winter and I went through 5 tons of coal at 200/ton =1000. Would have spent 3000 in propane to heat my entire house at 75 degrees.

My buddy has the same stove with same house size and heats the same way, only his duct work runs across the ceiling of his basement and into two seperate registers. I have no problem with using just the one.

I would even go larger and probably opt for the Oslo over the Castine. The side door feature of the Oslo is great feature that prevents ash spills and you will get an 2 hour extension in burn time.

I am surprised you didn't consider a Pacific Energy stove (a high quality Canadian made product) The Alderlea models T5 or T6 which have very similar looks as a Jotul.