🔍 Key Concepts

• Review how vacuum is created and maintained in a flash‑type distilling unit like the one shown • Identify which components in the illustration are open paths to the atmosphere (vents, drains, dump valves) • Consider whether a pump problem usually affects flow rate/pressure or vacuum tightness

💭 Think About

• Look at the components that, if left open or unlatched, would let air continuously enter the shell. Which choice refers to that kind of component? • Which pumps in the options move brine or distillate but do not normally seal the shell from the atmosphere? How would their malfunction affect vacuum? • On the illustration, trace the path from the evaporator shell to any overboard or drain connection. What has to be positively secured before you can pull vacuum?

✅ Before You Answer

• Identify on the drawing where the shell vent is and whether it goes to atmosphere or a closed system • Locate the dump/drain line at the bottom of the shell and note how it is secured during operation • Confirm which components are responsible for tightness of the shell versus just circulating fluids (brine pump, distillate pump)