Okay guys, Every thermometer I have seen gives three areas, creosote, burn zone, and over-fire. So can I assume that if I am within the "burn zone" burning season hard wood,oak hickory, walnut, you know good wood! that I am also burning clean and efficient? Over firing generally starts on these thermometer's at 575/600, and yet I here some of you talking about 600/650 and even 700 burn temps. So my question...."because as we all know the manufactures never give you a "over-fire" temperature, they just say not to do it." are the thermometers correct? would over firing start at 600* ? and if I am in the burn zone am I not creating creosote? For your info, I am burning a Hearthstone Heritage