I don't have any scientific data, but I know I came home last night to load up the stove, grab a shower, get mama some fresh clothes and headed back to the hospital. That was at 6pm. We all came home today at 4. The hall thermostat said 60Â°, outside temp was 25Â° with a good breeze. I stirred the coals up, threw four average sized ash splits on, and left the thermostat at 3. Stovetop was at 700 in short order. One hour later, the hall thermostat said 69, one hour after that it was at 75. Finally got it burned down enough to load for overnight. Somewhere a little over 2, with the blowers on med-low seems to be the ticket for now. The air temp is up in the house, but everything else is still pretty cool. That's three year seasoned red oak last night and tonight, stuffed as full as I can get it. I cleaned out the ashes Saturday, too.