I just got my #2 today and seasoned as per the instruction. While seasoning it I thought I would check the accuracy of the built in thermostat. I ran my probe through the top vent hole and clipped to the side rail for the shelves. The smoker heated up to 280 before it shut off. After it shut off it gradually cooled and when the temp. dropped down to 248 it turned on. My thermostat is a Maverick 732. Are the temps normal for the built in thermostat or should I be concerned?