OICEW Task 4.3.N

Start fresh water generator

MMA Method

In order to satisfy NVIC 17-14 Task 4.3.N , MMA students must:

NVIC Method

See NVIC method.

STCW Competence Knowledge, Understanding, and Proficiency

Operate main and auxiliary machinery and associated control systems

OICEW-A4.3 Preparation, operation, fault detection and necessary measures to prevent damage for the following machinery items and control systems

Auxiliary prime movers and associated systems
Condition Behavior Standard

On a motor vessel of at least 1,000 HP, on a simulator, or in a laboratory,

the candidate plans for and starts up the freshwater generator, describing actions as they are being performed.


Note 2 Task No. 4.3.W may be used as a substitute A candidate who does not perform this task will receive an endorsement that is limited to motor and/or gas-turbine propelled vessels without distilling plants.

The candidate:

  1. Opens the brine pump/eductor overboard skin valve;

  2. Opens the brine pump eductor saltwater supply valve;

  3. Opens the vacuum pump/eductor saltwater supply valve;

  4. Opens the saltwater feed pump discharge and suction valves;

  5. Starts the saltwater feed pump to supply both the evaporator eductors;

  6. Closes the vacuum breaker valve atop the evaporator shell;

  7. Adjusts the brine overboard discharge valve to maintain water level to just cover submerged tube nest in bottom of distiller;

  8. Delays continuing with operation until 75% of operational vacuum is attained;

  9. Opens the main heat source valve to distiller heating section;

  10. Adjusts the main-engine jacket water distiller heating section outlet valve to maintain proper jacket-water temperature differential between inlet and outlet;

  11. Adjusts the saltwater feed to distiller to maintain proper inlet temperature;

  12. Continues to regulate the brine overboard pump discharge to maintain seal and brine level;

  13. Starts the distillate pump;

  14. Energizes the salinity indicating panel and verifies the three- way valve is de-energized and distillate is re-circulated to the evaporator;

  15. Energizes the salinity indicating panel and verifies the three- way valve is de-energized and distillate is re-circulated to the evaporator;

  16. Continues to adjust the saltwater supply valve, controlling saltwater feed temperature, and brine overboard flow rate;

  17. Monitors the distillate pump salinity level output;

  18. Verifies the tank to be replenished is lined up;

  19. Energizes the three-way valve when the distillate salinity level is below alarm level;

  20. Verifies the salinity meter reading by comparing to chemical test of a 50 ml sample;

  21. Records the meter reading once discharge to tank has been established; and

  22. Takes proper action to prevent safety and pollution violations.