Failure to establish sufficient vacuum when starting up the unit shown in the illustration may be the result of __________. MO-0110

Correct Answer: Option B — neglecting to close the vent shell

The vent shell must be closed to isolate the evaporator chamber from the atmosphere, allowing the vacuum pump or ejector to evacuate air. Failure to seal this vent prevents the establishment of the necessary vacuum required for low-temperature evaporation, a fundamental operational requirement for vacuum-type marine freshwater generators.