What must be functioning properly along with the airflow transmitter when performing the CRTM on the automatic boiler system?

In the context of the CRTM (Calibration and Response Time Measurement) on an automatic boiler system, the minimum signal selector plays a crucial role in ensuring that the system operates correctly. When conducting tests related to airflow, it is essential to have the minimum signal selector functioning properly because this device helps determine the lowest operational signal that can be reliably interpreted by the control system. This capability is vital for maintaining the safety and efficiency of the boiler, as it ensures that the airflow measurements are accurate, which directly impacts combustion efficiency and system performance.

The minimum signal selector ensures that any readings below a certain threshold are recognized as inadequate and thus alerts operators to potential issues before they escalate. This aspect is particularly significant in managing the balance between fuel and air, which is critical for safe boiler operation and preventing unsafe conditions, such as incomplete combustion or excessive emissions. By having the minimum signal selector in proper working order, operators can trust the system’s responsiveness when adjustments are made during the calibration process.