What length of hard suction is recommended for drafting?

What length of hard suction is recommended for drafting?

• A. 10 Feet
• B. 20 Feet
• C. 30 Feet
• D. 40 Feet

Answer: (B)

Drafting relies on atmospheric pressure pulling water into the pump through the suction line. The longer the suction hose, the more friction loss and potential air leaks you introduce, which can break the prime and cut into the pump’s ability to develop discharge. About twenty feet of hard suction strikes a practical balance: it’s long enough to reach a water source from typical pump positions, while staying short enough to keep friction losses and joint leaks manageable so the pump can maintain prime and effective flow. A shorter length, like ten feet, may not reach some sources without repositioning, while longer lengths—thirty or forty feet—increase friction head and the chance of air leaks, making priming harder and reducing performance.

Drafting relies on atmospheric pressure pulling water into the pump through the suction line. The longer the suction hose, the more friction loss and potential air leaks you introduce, which can break the prime and cut into the pump’s ability to develop discharge. About twenty feet of hard suction strikes a practical balance: it’s long enough to reach a water source from typical pump positions, while staying short enough to keep friction losses and joint leaks manageable so the pump can maintain prime and effective flow.

A shorter length, like ten feet, may not reach some sources without repositioning, while longer lengths—thirty or forty feet—increase friction head and the chance of air leaks, making priming harder and reducing performance.