What is dead-heading and how do properly positioned valves help prevent it?

• A. Dead-heading is the condition where flow is blocked causing excessive head; properly positioned valves help prevent it.
• B. Dead-heading is the process of increasing flow to system.
• C. Dead-heading means the pump is fully lubricated.
• D. Dead-heading relates to battery discharge.

Answer: (A)

Dead-heading happens when a pump runs but there is little to no flow because the discharge path is blocked or all downstream valves are closed. The impeller still develops pressure (head), but with nowhere for the liquid to go, flow stays near zero. That high head with almost no flow can overwork the pump, leading to overheating, bearing and seal damage, and possible motor or prime mover trouble.

Positioned valves help prevent this by ensuring there’s a safe path for fluid or a relief path when valve positions change. A bypass or relief path, and properly located isolation and check valves, keep some flow or pressure relief available so the pump can’t be forced into a dead-head condition. This maintains cooling and lubrication and protects the equipment during operation and testing.

Other options don’t describe dead-heading: increasing flow, pump lubrication, or battery discharge aren’t the condition described here.