My BIL has an F600 and when I visit and such I'll tend the stove.
I can easily get her rolling 550-625 before knocking the front draft control down 75% or more.
You should be able to
easily over fire that stove for any length of time with the front draft control wide open......unless...
You have poorly seasoned wood, weak draft, inadequate coal bed or inexperience operating the stove (maybe a combination of these.)
We felled a red oak back in Sept. 08, split and stacked first week of Jan 09. For the hell of it.... I busted a split open last week and no surprise here, still a scent, some color and had dampness to it.
Your fire should be Rock'in & Rolling like my F500 here:
Stove temp 600, draft control knocked down 75%, 18 month old Black Birch & Hickory
WoodButcher