If you are going by the gauge on the door, it may be way off. check the temp on each rack with a digital. push the probe thru a small potato to hold if off the grill.
If the door thermometer is way far off, call customer service, they are very responsive at Smoke Hollow.
Mine is easy to run at 230-250F, but I have water in the pan, and wood chips in the chip pan over the flame, both of which could make a difference.