I was playing with it all weekend and yesterday I put what I would consider a full load (about 9 or 10 splits) on nice hot coals. The temp inside the blower area got to 500+ and stayed steady. There were secondaries for so long the middle tube started to look red. I put the fan on high and sat there sweating it out. Literally! I thought it handled it pretty well, but I had the air all the way down, which I know is a no-no with the fan on but that thing would have taken off! Do you use the fan with the air shut all the way down or do you always leave the 1/2" as stated in the manual? Edit, not sure what the mix of wood was. Probably not much hardwood so all oak or something may have different results.