I just installed 2 char-broil themometers in my mini GOSM, 1 below the top rack and 1 below the bottom rack. I checked them both in boiling water and they were pretty close, thought they read a little high. When I did a test run on the GOSM I noticed a wide variation in temp, ( top rack 250, bottom 230, and stock 300
). Is this normal ? Is the stock themometer that far off, or is it a problem with the new ones ?