Spectra Watermakers NEWPORT 400 Mk II, Installation & Owner'S Manual

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35
Me mbrane Cl eaning
For normal cleanin g, the SC - 3 Acid C leanin g Compound is used fir st, then the SC - 2 Alkal ine
Cleanin g Compound. If known b io - foul in g is present, the SC - 2 may be used f irst. U se hot water
if poss ib le, up to 120° F (45C) is recommended as it greatly enhances the ability of the cleaners
to do their jobs.
If the history of the system is unknown or has be en left “unpickled” for an extend ed length of
time and bio lo g ical growth is present, it is recom mended that the system is cleaned with S C - 2,
usin g an alternat e source of un chlorinated fresh wa ter before the system is run under pr essure.
A s imp le test can be performed to see if bio lo g ical growth has occurred. Before runnin g the
system, remove the prefilters and examine their condition If the housing s are full of smel ly di s-
colored water, the system was not properly stored. Install clean prefi lters if they were bad. Next
check the membrane. At tach the brine discharge service hose and lead to a buck et. Op en the
pressure relief valve one turn, and manually run th e system for 30 seconds. Examine the brine
water: if it’s di scolored and sme ll s bad, perform an SC - 2 cleanin g w ith an alternate sourc e of
unchlorinated water before runnin g the sy stem pressur i zed. If the br ine is fa irly clean, the sy s-
tem can be purged, run normal ly, and checked for performance. Clean th e membranes only if
performance is reduced.
Heating the water i s preferable. One way to do this i s to f ind a camp stove and use a lar ge
stainless steel pot to hea t the solution in. The cleanin g so lution throu ghout the system wi l l heat
as it circulates in and out of the pot. An altern ative is to heat the one or two gallon s of in itia l
water to 120° on the main stove before mixin g in the cleaner and circulating it into the system.
Periodically stop and reheat the solution.
Perform the cleaning procedu res while the ship is in acc eptable sea water for purg ing and testing .
  There are two types of cleaners: acid and alkaline. The acid cleaner (SC - 3) wi l l remove m in-
eral scalin g. The alkal ine cleaner (SC - 2) is u sed to remove biolo gical by - products, oi l, and
dirt particles that get past the prefilters. If me mbrane performance is reduced and they h ave
not been pickled rec ently, cleaning w ith both chemicals is recommended. The acid cleaner
should be used first. If the membrane f ails to respond to both cleanings, this is an indication
of another problem with the system, or that it is time to replace th e membrane. Conta ct
Spectra Watermakers befor e removing a me mbrane.
  The me mbranes need to be cleaned only when operatin g pressures have r isen more than
10% or the produc t quality degrades. The leadin g cause of foulin g in mar ine use is fro m
biolo g ical growth that occurs when the system is left unused w ithout flush in g or p ickl in g.
Foul in g from m ineral scal in g can happen during operation under cert ain sea wat er condi-
tions, and from rust. Monitor the produ ct salinity and fe ed pressure b ar graphs for higher
than normal readin gs for the condit ions. Other condit ions can cause hi gh pressure such as
cold feed water or clo g ged fi lters. Low product f low is usual ly due to lo w vo ltage, dama ged
feed pump or Clark Pump issues. Look for all other causes b efore cleaning the membrane.
Membrane life can be shortened by exc essive cleaning.
The M e mbranes