Is your thermometer showing an incorrect temperature?
You can test the performance of your thermometer yourself. An instructional video of this can be found here. Dismantle the thermometer from the dome (there is a nut on the inside that you can unscrew).Test if the thermometer reads 100 degrees Celsius after you put it in a pot of boiling water. Is this not the case? Then the thermometer is not working properly and should be replaced. The dome thermometer has a 1-year warranty. Please contact customer if the thermometer becomes defective within this period.
Does your dome thermometer indicate a different temperature than the thermometer at the grill/rack? Don’t panic! This is not surprising. The rack/the grill is closer to the fire. Therefore, it is regularly the case that the temperature measured at the rack is much higher. A difference of, say, 35 degrees is certainly not unusual.