What pressures should be monitored when troubleshooting a pump cavitation issue?

Monitoring both vacuum and atmospheric pressures is crucial when troubleshooting a pump cavitation issue because it provides a comprehensive understanding of the operating conditions surrounding the pump.

Cavitation occurs when the pressure in the pump drops below the vapor pressure of the liquid, leading to the formation of vapor bubbles. By examining vacuum pressure, you can assess how much suction the pump is experiencing. High vacuum or low absolute pressure indicates that the pump might not be receiving enough liquid, which can lead to cavitation.

Simultaneously, monitoring atmospheric pressure helps to establish the baseline conditions under which the pump operates, as variations in atmospheric pressure can affect the total dynamic head and potential for cavitation.

Together, these readings allow for a thorough analysis of the system, helping to identify whether the cavitation is caused by low suction pressure, insufficient NPSH (Net Positive Suction Head), or other operational issues. Understanding both pressures is essential for troubleshooting and ensuring proper pump functionality.