Total suction head is defined as the gauge reading at suction converted to feet of liquid plus velocity head.

• A. Gauge reading at suction converted to feet of liquid plus velocity head
• B. Gauge reading at suction only
• C. Static head only
• D. Discharge head plus pump efficiency

Answer: (A)

Total suction head represents the energy available at the pump suction carried in the fluid before it enters the impeller. It combines the pressure energy in the suction line (gauge pressure converted to feet of liquid) with the kinetic energy of the moving fluid (velocity head). In other words, you take the suction gauge reading, convert that pressure to equivalent feet of water, and add the velocity head v^2/(2g). The vertical static lift or elevation difference is not part of this particular definition of total suction head on the suction side; those terms appear in other parts of the overall head balance.

That’s why the correct description is the gauge reading at suction converted to feet of liquid plus velocity head. For context, if suction pressure is 10 psi and the fluid velocity in the suction line is 4 ft/s, the pressure head is about 23.1 ft, and the velocity head is roughly 0.25 ft, giving a total suction head of about 23.35 ft.