A customer will complain that her burner, usually the big, front favorite one, will no longer stay at simmer or medium heat. It will only glow full blast - red hot. This is simply a bad infinite switch. An infinite switch includes a bi-metal device that cycles the power on and off depending on the the chosen setting. A low setting only turns the power on 10% of the time. A broken bi-metal will just keep the power on constantly. Replace the switch!
