THE SYMPTOM - The user is preheating the grill to 'burn off the previous cookout's residue' and, for no apparent reason, the glass on the grill simply shatters. The reason for this is caused by a faulty burner below the defusers (i.e. rocks, etc.) What is happening is the burner has corroded or split and is letting out a disproportionate amount of heat at one spot. While the glass is tempered, it cannot take high temperatures being exerted on different portions of the surface. The result is that the glass shatters and possibly ruins a good cookout.
SOLUTION - Sometime before your next cookout, open the hood, remove the grates, take out the rocks (or remove the metal defusers, if possible) and look at the burners while the are lit. You may even be able to do this from holes on the lower portion of the body of the grill. Make sure each outlet is producing the same consistent blue flame. If not, you have a problem and the burner should be replaced. Better to replace it now than when replacing both the burner AND the glass.
