Which of the following lists the common signs of a leaking suction line?

• A. Visible air bubbles at joints, hissing at pipe fittings, decreased suction pressure, and wet spots.
• B. No signs of leakage or pressure changes.
• C. Increased discharge pressure with no suction changes.
• D. Only wet spots without other signs.

Answer: (A)

Air entering the suction side through leaks causes the pump to lose prime and performance. The most reliable indicators are visible air bubbles at joints, a hissing sound at pipe fittings, a decrease in suction pressure, and wet spots around the leak. Together, these signs show both air ingress and fluid escape on the suction line, which is what a leak would produce. The other options don’t fit: a lack of leakage signs means no leak; increased discharge pressure with no suction changes points to a discharge-side issue; wet spots alone could come from a leak but don’t necessarily indicate suction-side air ingress and loss of suction.