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

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43
Operation and Repair Bulle tins
Th e follo wing do cu m ents ar e se ctions of our co m plete s er v ic e bulletin set.
Th ese a re a v a ilable on our w ebsite w w w .spe ctra w ater m ak ers. co m
MEMBR ANE C A RE
Membrane life is affected by a large number of factors and is somewhat unpredictable. A
bi g com mercial p lant runnin g 24/7 wi l l get 10 to 12 years out of a se t of membranes. But
they do all kinds of fancy chemical in jections and never shut the thing off. Mo st cruisers are
lucky to get five or s ix years out of one. You hear of the eight or ten year old membrane now
and then. The big gest ki l lers of me mbranes are lack of use, chlorine damage, and i mproper
storage.
Don’t let membranes s it around with sea water or stale fresh water in them. Biolo gical
growth w i ll occur in the me mbrane. Here at th e fa ctory we frequ ently get back membranes
for inspection that reek of hydrogen sulfide (rotten eg gs). Th i s odor i s produce by anaerobic
bacteria th at live in an unused membrane, feeding on whatever animal or vegetable matter is
trapped in it from the plankton that gets through the system. Membranes badly fou led in
this way can seldom be saved. These bacteria are always present but are inhibited by the
oxygen in sea water while the unit is in frequent use, by scheduled fresh water flushes, or by
pickl in g. Keepin g the prefilters clean i s also i mportant in preventing bio - fou l in g. If your
prefilters are allowed to become a breeding ground for bacteria (get smel ly), the contamina-
tion wi l l spread throughout the system. When we cut open a f ailed membrane we also f ind
mi ldew, another form of bio fou l in g, probably due to lon g term stora ge with no b iocide or
stale biocide.
After many hours of water makin g m ineral depos its w il l for m and must be di sso lved away
with an acid cleaner. Alkal ine cleaners are used for bio - foulin g. C leanin g chemical s, espe-
cially the alkal ine, are not good for the membrane. Every time you clean the membrane it
shortens its l ife. Clean only when necessary, and avoid cleaning as a “diagnostic tool”.
Chlorine w i ll destroy a me mbrane in m inutes. It attacks th e material that the membrane is
made from. A lways use product water or water filtered slowly throu gh a charcoal filter for
flush in g and chemical treatments.
Oi l s imp ly p lu gs up the matrix of the membrane and clo gs it up. We have brought back oil
fouled membranes w ith Joy soap ( See MB - 5 C leanin g w ith Detergent.)
For storage we recommend us in g propy lene g lycol potable water system antifreeze if avail-
able. It can safely be left in the system for one ye ar and will keep thin gs fro m freez in g in
cold conditions. It is hard to find in warm c li mates, and takes up a lot of room on a small
boat, so our SC - 1 is best for tropical crui sin g.
Given good care a membrane wil l eventually just start to slow ly fade away. The feed pres-
sure may rise and/or the ppm go up. Hardly ever wi l l they just fai l overni ght.
8/13/04