Spectra Watermakers AQUIFER 150, Owner'S Manual

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Membrane Cleaning
For normal cleaning, the SC-3 Acid Cleaning Compound is used first, then the SC-2 Alkaline
Cleaning Compound. If known bio-fouling is present, the SC-2 may be used first. Using hot wa-
ter if possible, up to 120° (45C) is recommended, as it greatly enhances the ability of the clean-
ers to do their jobs.
If the history of the system is unknown or it has been left “unpickled” for an extended length
of time and biological growth is present, it is recommended that the system is cleaned with SC
-2, using an alternate source of unchlorinated fresh water before the system is run under pres-
sure. A simple test can be performed to see if biological growth has occurred. Before running
the system, remove the prefilter and examine its condition. If the housing is full of smelly dis-
colored water, the system was not properly stored. Install a clean prefilter if it was bad. Next
check the membrane. Attach the feed and brine service hoses and lead them to a bucket of
clean de-chlorinated water. Open the pressure relief valve one turn, and manually run the sys-
tem for 30 seconds. Examine the brine water: if it’s discolored and smells bad, perform an SC-
2 cleaning with an alternate source of unchlorinated water before running the system pressur-
ized. If the brine is fairly clean, the system can be purged, run normally, and checked for per-
formance. Clean the membranes only if performance is reduced.
Heating the water is preferable. One way to do this is to find a camp stove and use a large
stainless steel pot to heat the solution in. The cleaning solution throughout the system will
heat as it circulates in and out of the pot. An alternative is to heat the one or two gallons of
initial water to 120° on a stove before mixing in the cleaner and circulating it into the system.
Periodically stop and reheat the solution.
There are two types of cleaners: acid and alkaline. The acid cleaner (SC-3) will remove mineral
scaling. The alkaline cleaner (SC-2) is used to remove biological by-products, oil, and dirt parti-
cles that get past the prefilters. If membrane performance is reduced and it has not been
“pickled” recently, cleaning with both chemicals is recommended. The acid cleaner should be
used first. Colloidal Metals and Metal Oxides are very difficult to remove. If the membrane
fails to respond to both cleanings, this is an indication of another problem with the system, or
that it is time to replace the membrane. Contact Spectra Watermakers before removing a
membrane.
T
he membranes need to be cleaned only when feed pressure begins to rise due to fouling or
the product quality degrades. The primary causes of fouling are biological growth and scaling.
Biological growth occurs when the system is left unused without flushing or pickling. Fouling
from mineral scaling will form when the feed water is “hard” or high in carbonates. Very small
“colloidal metal” and metal oxide particles can also plug the pores in the membrane. Monitor
the product salinity and feed pressure for higher than normal readings for the existing condi-
tions. Other conditions can cause high pressure such as cold feed water or clogged filters. Low
product flow is usually due to low voltage, damaged feed pump or Clark Pump. Look for all
other causes before cleaning the membrane. Membrane life can be shortened by excessive
cleaning.
The Membranes