🔍 Key Concepts

• Purpose of vent valves vs. drain valves in a shell-and-tube heat exchanger • How air pockets affect heat transfer efficiency in a cooler • What type of contamination (air vs. sediment) is most critical at the moment of starting the cooler

💭 Think About

• Ask yourself: at startup, what is most likely to be trapped at the highest points in the exchanger, and how does that affect heat transfer? • Think about the normal function of a vent compared to a drain. Which one is designed to remove gases and which for liquids/solids? • Consider what will happen to jacket water flow and temperature control if air is left in the shell or tubes.

✅ Before You Answer

• Identify which valves are located at or near the highest points on the exchanger and which are at the lowest points. • Decide whether air or sediment is the primary concern when first placing the cooler in service for best heat transfer. • Confirm which valves (vent or drain) you would expect to open briefly and then reclose to purge that unwanted material.