6
– MAINTENANCE (ROUTINE AND SPECIAL)
COD.
30Z12/24.B.2021
EN
THE PRESENT MANUAL BELONGS TO -
Schenker Italia
- ALL RIGHTS RESERVED
36
Purge air from the system
periodically by opening
slightly the
depressurization valve for
2-3 minutes
Every 15-20 days
6.2 Check the watermaker working pressure
The working pressure of the pump is indicated on the
manometer of the main unit.
The working pressure depends on many factors, such
as water temperature, seawater salinity, batteries
voltage,
membranes
conditions,
typology
of
installation.
The pressure, in normal working conditions, is in the
range 6,5-7,5 bar. There is a periodic small pressure
peak (during commutation) of 0,1-0,2 bar.
If the average pressure exceeds the above range, it is necessary to check the membranes cleanliness. If the
pressure exceeds the abovementioned range,
it’s highly likely that the membranes are dirty or clogged, and it
is necessary to perform a cleaning with the chemical SC1. If the cleaning with SC1 is not enough to reduce
the pressure, it might be necessary an alkaline washing with the cleaning SC2.
6.3 Check for leaks
It is necessary to perform this verification at every watermaker start-up and frequently, as possible leaks due
to accidental causes (hose bursting, hose clamp loosening, equipment failure, etc.) may occur causing
possible damages.
6.4 Check for membranes replacement
The reverse osmosis membranes last for an average period of time of 6-7 years. When the membranes are
old, the quality of water usually decreases whereas the working pressure increases. If chemical washings do
not produce significant improvements, it is recommended to replace the membranes.
6.5 Shutdown procedure
It is necessary to perform the shutdown procedure before standstills longer than 2-3 months, for instance
before the wintering.
The purpose of the shutdown is to flush the system. This might be useful in order to prevent the system from
the creation of organic and inorganic sediments, as well as inhibit the growth of bacteria that could reduce the
reverse osmosis membranes efficiency.
