Spectra Watermakers Farallon 1800, Installation And Operating Manual

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PF-4 PREFILTERS– Mk II SYSTEMS
Four different filters are used on these Spectra Watermakers to make sure that no damaging
foreign materials enter the system. There are 2 or 3 filters in the system to clean the feed water
of abrasive materials while the system is in operation, and a 4th filter that prevents the entrance
of chlorine during fresh water flushing.
During normal operation the feed water is filtered in two stages. First it enters a fine mesh
metal sea strainer then passes through a boost pump. This protects the boost pump from
damage. After passing through the boost pump the feed water enters the filter housings
containing 20 and 5 micron elements. These filters remove very fine particles which could
damage the Feed Pump or Clark pump, and which would shorten membrane life. Some
systems will only have a 5 micron filter.
Service schedules will vary widely depending on how and where the system is used. If large
amounts of feed water are run through the system in a relatively short period in biologically
fertile near shore waters, the prefilters will plug up, the pressure drop across the filters will rise,
product production and quality will drop, and the system will sense plugged filters and give a
SERVICE PREFILTERS alarm.
When operated only an hour or two a day in inland or near shore waters, the trapped plankton
will begin to decay in the filters long before the elements plug up, and the bacteria involved in
the decay will cause a “rotten egg” smell in the product water. This decay will set in overnight
in tropical waters, or after a week or two in high latitudes. If handled gently and changed
regularly before they get too smelly, filters in this service can be cleaned a limited number of
times. In crystal clear blue water conditions the filters may need to be cleaned much less
frequently.
The charcoal filter used in the fresh water flush system will not plug up unless you have some
incredibly dirty domestic water in your boat. About six months after installation the charcoal
filter element will lose its effectiveness at removing any membrane damaging chlorine which
may be present in domestic water. Charcoal filter elements must be replaced every six months
if there is ANY chance that chorine could be introduced into the flush water. Charcoal filter
elements cannot be cleaned.
To ensure that filter elements fit properly and remove chlorine effectively, they should be
purchased at factory authorized dealers.
06/03/04