CFESA Gas Practice Test 2025 – Complete Exam Prep

Whistling at the burner orifice is commonly caused by burrs left when the holes were drilled into the orifice. When the orifice is manufactured, if there are any rough edges, or burrs, these can disrupt the smooth flow of gas. As gas passes through the orifice, the presence of these burrs can create turbulence, leading to the whistling sound.

Smooth orifices allow gas to flow steadily and without disruption, while any irregularities can contribute to airflow issues, resulting in that characteristic whistling. Addressing the burrs through a proper finishing process during manufacturing or installation is essential to ensuring optimal burner performance and eliminating this noise.

In contrast, issues like air leakage in the gas line or low gas pressure may lead to other operational problems, but they typically would not result in a whistling sound coming specifically from the burner orifice. Similarly, incorrect burner adjustment can affect combustion efficiency or flame quality but does not specifically cause a whistling noise attributed to burrs in the orifice.