Refrigeration and Air Conditioning Mechanics (313A) Exam 2026 – 400 Free Practice Questions to Pass the Exam

A common symptom of a pump experiencing cavitation is excessive noise and vibration. Cavitation occurs when the pressure in the pump drops below the vapor pressure of the liquid, leading to the formation of vapor bubbles. As these bubbles form and then collapse or implode, they generate shock waves that produce significant noise, often described as a "gravel" or "marbles" sound. This phenomenon can result in vibration as the collapsing bubbles exert sudden forces on the pump components, causing wear and potentially damaging the pump over time.

In contrast, an increased flow rate is not typical of cavitation; rather, cavitation generally leads to flow restriction and may actually reduce the effective flow rate. Overheating of the motor can occur for various reasons but is not a direct symptom of cavitation. Similarly, decreased refrigerant pressure may be linked to other issues in the refrigeration system rather than being a clear symptom of cavitation specifically.