Fresh Water Generator - Low Production - Basic troubleshooting

FWG Schematic_resized

A basic troubleshooting for investigating FW Generator low production. Feel free to add more.

ā†’ Low fresh water production

A. Assuming proper Vacuum

  1. Reduced heat transfer in evaporator
    (observing thermometers)

    a) (increased difference between Jack W In - Out temp)
    inlet / outlet valves should be fully open and bypass closed

    b) (reduced difference between Jack W In - Out temp)
    evaporator is fouled (checmical cleaning or drilling of clogged tubes)

    c) (Proper difference between Jack W In - Out temp, BUT BOTH REDUCED)
    Low load of M/E
    or Jack W Cooler operating at low temp

  2. Reduced heat transfer at the condenser
    (observing thermometers)

    a) (higher temperature at shell and high SW temp difference between Condenser Inlet-Outlet temp)
    low flow of ejector pump (pump wear)

    b) (small difference between condenser Inlet-Outlet temp)
    blockage/fouling at condenser

  3. Distilled pump worn (losses suction - mouth rings replacement)

  4. Faulty flowmeter (actual production as seen at FW tanks is ok)

  5. Leaks or blockages on piping/fittings downstream of FW pump

B. Assuming improper Vacuum

  1. Air Leak
    a) air leaking on air valve on the body of FWG, or air leaking of sight glass joints, or body

    b) air leak of the distilled water pump seal, seal or non return valve downstream

  2. Ejector inlet pressure is low

    a) ejector pump inlet-outlet and ovbd valves should be open fully

    b) dirty suction strainer of ejector pump,

    c) ejector pump wear

    1. Ejector outlet pressure is low

    a) orifice at the ejector is worn or blocked

C. Assuming High Salinity

  1. faulty salinometer
  2. Solenoid valve controlled by Salinometer controller faulty or valve leaking
  3. Demister fouled
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@Spyros.P thank you for the thorough guidance.
A datasheet as per the attached can also assist in tracing and resolving possible issues.
Fresh water generatro Operation Data Sheet for X 1.pdf (16.9 KB)