I'm getting great heat, even overnight and waking up to red bed of coals and heat still coming out of the blower. I am using pretty good wood - dry on the inside for sure but maybe a bit wet outside but well below 18%, most is 10%-12% outside only. On start-up, I can get into the active state for the cat. I let it go 20-30 mins, close the bypass, turn on the blower and lower the thermostat to the lowest setting. It's well in the red for a few hours but after that drops to the inactive zone, even though there is 1/3 of the wood left Still plenty of heat though. Prior to that (when it's in the active state) the cat is red hot and wood is hot red as well. I do see an burst of flame however (almost like I turned the thermostat up all the way - but I don't touch it. This occurs about every 5 mins than it's out. As far as I can tell I am following all instructions. Curious of others are experience similar active state times as well as the flair ups when the thermostat is set low? I'm tried small fires and packing it full with similar results.