How do I pickle an Enwa 3200 watermaker for storage?

Pickle your Enwa 3200 by flushing out the seawater with chlorine-free fresh water, circulating a compatible membrane preservative through the designated service circuit, and leaving the membranes completely wet. Before starting, confirm the preservative, dilution and valve arrangement for your installation: Spectra SC-1 instructions and Clark Pump valve settings do not apply to the Enwa 3200.

Check membranes and service connections

Find the unit's serial number, membrane identification and any instructions supplied with a replacement membrane. These establish chemical compatibility; the Enwa model name alone cannot identify the membranes or seals currently fitted.

Locate the seawater inlet seacock, prefilter housings, fresh-water flush connection, pressure control, service suction connection, brine discharge and product-water diversion valve. Trace the hoses by hand, particularly if a previous owner has altered the installation.

Before mixing chemicals, confirm:

• The approved storage chemical and its final working concentration.
• The required solution volume, circulation time and renewal interval.
• Which pump circulates the solution and how to release operating pressure.
• Whether the product-water outlet must drain separately during treatment.

Sodium metabisulphite preserves many conventional reverse-osmosis membranes, but use it only if approved for the complete Enwa installation. Sodium bisulphate is a different chemical; a similar name or another watermaker's recipe does not establish compatibility.

Flush out the seawater

Prepare a clean plastic bucket, compatible service hoses, a measuring jug and enough chlorine-free fresh water for flushing and mixing. Watermaker product water is a useful choice. Dock water needs effective dechlorination before it reaches a chlorine-sensitive membrane.

Wear gloves and eye protection when handling preservative. Provide ventilation, and never mix it with acids, bleach or other cleaners.

1. Run the normal fresh-water shutdown flush, following the Enwa valve sequence.
2. Stop the unit, isolate its electrical supply while changing connections, and close the seawater inlet seacock.
3. Release operating pressure through the Enwa pressure-control arrangement before opening any service connection.
4. Inspect the prefilter housings and remove dirty cartridges. Clean the housings and fit or remove cartridges as the storage procedure specifies.
5. Connect the service suction and brine return hoses to the mixing bucket, securing their ends.

Do not copy the half-turn pressure-relief setting used on a Spectra Clark Pump. The Enwa pressure regulator and pumping arrangement require their own procedure.

Circulate the approved preservative

Mix the preservative thoroughly in chlorine-free water before drawing it into the system. Include the water retained in the machine when calculating the working concentration, as well as the bucket contents. Residual flushing water can otherwise dilute the treatment below its specified strength.