Mailport June 2012 Issue

Mailport: June 2012

Sanitation Plumbing

sanitation plumbing
Photos by Frank Lanier and Drew Frye

The sanitation plumbing, part of our vent filter test, included a water-filled bypass loop that acted as an odor trap. This made adding a second end valve unnecessary, in our opinion.

In reference to your “Avoid Plugging with Proper Vent Installation” sidebar and photos in the March 2012 issue: If you’re going to backflush the vent, I think it will take more than just a shutoff valve on the filter outlet, because shutting this valve will not allow the backflush water to return to the tank. It would take a filter bypass arrangement, also with a valve, for this to work. In normal operation, the bypass valve would be shut and the filter valve open. For backflushing, the bypass would be opened and the filter shut.

Jordan Ruzz


In the installation described and pictured, there is a bypass loop, incorporating a water-filled trap as an odor seal. A shutoff valve on the filter outlet (the end connected to the through hull) prevents water from entering the filter, forcing it through the bypass, just as you suggest. We didn’t feel the design required valves on both ends of the filter, since with one end sealed, trapped air prevents water from entering the filter; however, placing a valve at both ends would be a safe and conservative approach. In our design, the bypass is always open, sealed only by a water-filled trap.

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Comments (1)

This is one reason the boat yard we use (burr bros boats) offers stainless steel penants in addition to the generous sized regular penants during hurricane season. In Irene last year, BBB lost no boats (including ours), where other boats did break free from other moorings. After the hurricane we notices some varnish wore through under the chock on the side of the boat with the nylon penant (and made a minor cut in the penant), but no damage on the side with the stainless penant (as it is very stiff and stands out from the chock). Great service from the boat yard! Probably will pull the boat next time to reduce the stress level!

Very good tips and information on nylon lines!

Posted by: Phantomracer | May 23, 2012 1:53 PM    Report this comment

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