Roll-out switchs are designed to detect if the flame within the furnace ever became lazy (layed down instead of stand up) and didn't flow up through the heat exchanger. If a flame were to roll out of the burner box, a dangerous sitiuation could occur. This could cause a house fire. Roll-out switches are designed to register a specific tempertaure setting. When a flame is directly on them, they sense the temperature and respond by opening the burner circuit. This will instanly shut off the gas to the appliance. Some switches will reset automaticly after they cool down and some must be manually rested.To manually reset a roll-out switch, press the button that is located on top of the switch.

Manual Roll-Out Switch		Auto Resetting Limit Switch