Reliable and easy to use, the iconic Weber kettle grill has been a backyard fixture for over half a century. Weber grills use an intake damper, or lower vent, and an exhaust damper, or lid vent, to control temperature. Oxygen enters the lower vent and fuels the charcoal, while the lid vent lets heat and smoke exit. You have to know your grill's temperature to control it, and the supplied grill thermometer is usually off by 50 degrees. Replace it with grill thermometer, such as a digital version with a remote that lets you check the temperature without opening the lid, to effectively use your Weber's vents.
Start your coals in a chimney starter above wadded newspaper and allow them to ash over, which takes 5 to 10 minutes. Open the grill's top and bottom vents all the way; move the lower vent's handle all the way to the left and rotate the lid's vent cover clockwise until the holes aren't obstructed. Lift out the cooking grid and empty the chimney starter full of lit charcoal in the tray.
Replace the cooking grid and close the lid. Let the grill heat to about 350 degrees Fahrenheit, about 10 to 15 minutes. The outside temperature and wind affect how long it takes the grill to heat.
Slide the lower vent's handle to the center position when the grill reaches 350 F. Let the grill heat another 5 minutes.
Check the grill temperature once more before you lay the food down; it should stay between 325 and 350 F. If you need to increase the temperature by up to 50 degrees, open the bottom vent by sliding the handle about 1/2 inch to the left; to lower the temperature by up to 50 degrees, slide the handle to the right about 1/2 inch.
Empty 3/4 of a chimney full of charcoal onto one side of the charcoal tray. Set a water pan on the other side.
Adjust the lid's vent and the lower vent to their open positions. Let the grill heat until it reaches 350 to 400 F.
Adjust the lid's vent until it's 1/3 open. Close the lower vent completely.
Check the grill temperature in 5 minutes. It should hover around 225 F.