New York Low Pressure Boiler Certificate of Fitness (COF) Practice Test

Which component functions as flame detection control for a boiler?

1. Smoke detector

2. Photoelectric cell

3. Atomizer

4. Aquastat

The correct answer is: Photoelectric cell

A photoelectric cell functions as a flame detection control for a boiler by sensing the presence of light generated by the flame. This type of device detects the intensity and frequency of the light emitted from the combustion process, allowing it to determine whether the flame is present and operating correctly. If the flame goes out, the photoelectric cell can send a signal to the boiler's control system to shut down the burner, thereby preventing unburned fuel from entering the system, which is crucial for safety and efficient operation. In contrast, other components do not serve the flame detection role. A smoke detector is designed to detect smoke particles and is used more for safety and fire alarm purposes rather than for direct flame detection within the boiler's combustion system. An atomizer is involved in the process of atomizing fuel for better combustion but does not have any role in detecting flames. Lastly, an aquastat is responsible for monitoring the temperature of the water within the boiler, but it does not provide flame detection capability. Each of these components has distinct functions that do not overlap with the flame detection responsibilities of a photoelectric cell.