The main problem in the ICW will be silting of the filters. My big RO rig came with one filter and a centrifugal feed water pump (to feed water to the high pressure pump). I added a second filter in series with the first. These filters are the type sold in Home Depot to mount under the sink. The elements are about 2 inches in diameter and about a foot long. I use the pleated type because they can be rinsed out. They come in various micron ratings. I use a 20 micron, then a 5 micron in series to spread the load.
I have come to believe that two five micron filters in parallel would be better. Since one wants to filter out everything down to five microns anyway, why bother with the twenty? I put in two filters because it is easier to rinse two filters at one time than to rinse one filter twice as many times. The best price for these filter elements I have found is Farm Supply by the case. There is some variation in the number of pleats. I once found one filter in a case that had many more pleats that all the others (which means servicing it at longer intervals because it has more surface area to collect debris) but have been unable to find a source for them. There are sophisticated centrifugal mechanical filters but they are pricey and use power. The best course may be what Andina did: to install the smallest swimming pool sand filter you can find. The sand filter is very effective and can be back-flushed clean with the twist of a valve. If you don't already have it, you need a way to avoid cavitating the high pressure pump when the filters become so plugged that the input pressure to the HP pump gets around zero or below. The HP pump will complain when that happens. If you can hear it you can shut it down and service the filters. If unattended, you will need some sort of pressure sensor that will shut down the HP pump automatically to prevent starving it. It is possible, but complicated, to automate the flushing cycle. Norm S/V Bandersnatch Lying Julington Creek FL QUESTION TO THE GROUP: What mods do I need to make to make our watermaker bullet proof for use in the waters of or near the ICW??? Seems to me a couple prefilters and pump would protect it, but anyone have any info handy on what we need? _______________________________________________ Liveaboard mailing list [email protected] To adjust your membership settings over the web http://www.liveaboardnow.org/mailman/listinfo/liveaboard To subscribe send an email to [email protected] To unsubscribe send an email to [email protected] The archives are at http://www.liveaboardnow.org/pipermail/liveaboard/ To search the archives http://www.mail-archive.com/[email protected] The Mailman Users Guide can be found here http://www.gnu.org/software/mailman/mailman-member/index.html
