These pellets are only giving me 10 to 11 hours. Feed at 3.75, room temp manual, 72-73. I haven't changed any of the settings since burning the LaCretes or the Logic. When it's above 20 outside I get good burn times. But it got cold last night and the p61 must have been hungry, cause the slide plate was showing when checked. I was getting 14 hours plus out of the LaCretes all winter long.