What is the purpose of the high limit switch in a furnace and how does it function to ensure the safety and efficiency of the heating system?

The purpose of the high limit switch in a furnace is to monitor the temperature inside the furnace. If the temperature exceeds a safe level, the switch shuts off the burner to prevent overheating and potential damage. This helps ensure the safety and efficiency of the heating system by preventing fires and protecting the components from excessive heat.