Which device is used to confirm that the fan motor is operational?

The air flow switch is specifically designed to confirm that the fan motor is operational by detecting the movement of air. When the fan motor runs, it creates airflow, which activates the air flow switch. If there is no airflow, the switch will not close, indicating that the fan may not be functioning properly.

In contrast, a temperature gauge measures the temperature of the air or the environment, but it does not directly indicate whether air is moving or if the fan itself is running. A pressure regulator manages the pressure in a system but doesn't confirm motor operation. A ventilation controller manages overall air quality and flow but, similar to the temperature gauge, does not provide direct confirmation of the motor's operational status.

Thus, the air flow switch is the appropriate device for ensuring that the fan motor is indeed operational by sensing the actual airflow produced by the motor.