Step1: Lock out electrical power at breaker, check no voltage present with a tester before beginning work.
Step2: Remove control knob and front panel to access the switch assembly inside the unit.
Step3: Disconnect wiring from terminals, labeling or noting positions for correct reinstallation later.
Step4: Remove mounting hardware and extract the faulty switch from the control bracket assembly.
Step5: Install new switch, secure mounting, and reconnect wires to matching terminals.
Step6: Reassemble panel, restore power, and test all heat settings for proper operation.