🔍 Key Concepts

• Main condenser vacuum and how it is maintained underway • Purpose of the atmospheric drain tank / fresh water collector in relation to the condenser and feed system • What happens when a system designed to handle drains and air loses its water seal or runs dry

💭 Think About

• Think about what the atmospheric drain tank is connected to and whether its level directly controls steam pressure, condensate flow, or condenser vacuum. • Ask yourself: if the tank level keeps going down while steaming, what part of the steam–condensate–vacuum system would be most sensitive to that change? • Consider which option describes a consequence that would only appear after the tank is actually empty, not while it still has some level.

✅ Before You Answer

• Verify which component (contaminated evaporator, contaminated steam system pressure, automatic make‑up, or main condenser vacuum) is actually dependent on the drain tank maintaining a water seal or level. • Check whether an automatic make‑up via vacuum drag is a standard function of an atmospheric drain tank or sounds like an extra feature that would have to be specifically installed. • Confirm which outcome would most seriously affect the safe, continuous operation of the propulsion plant while underway if the drain tank is allowed to run dry.