Calypso's black water installation has vented loops on the discharge hoses which a routed above the water line. I did not put one in the flushing water supply but I am considering adding one.
A note on hoses. Buy the best smooth bore hose available (I used Trident), route to avoid pooling, and flush with clean water (fresh for those in salt) to avoid odor permeation when the system will not be used for a few days. Also, avoid using all rigid plastic pipe (looked at the linked C&C 40 project where PVC was used) if your installation will be used away from the dock. I believe a PVC installation onboard a fiberglass boat underway would suffer from vibration and flex stress/failure given enough time or sea miles. Martin Calypso 1971 C&C 43 Seattle -----Original Message----- From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of djhaug...@juno.com Sent: Tuesday, October 22, 2013 3:59 PM To: w...@wbryant.com; cnc-list@cnc-list.com Subject: Re: Stus-List New Head and holding tank system. So no vented loop? just straight to a tank? what stops things from wanting to go back through the joker valve? ---------- Original Message ---------- From: Wally Bryant <w...@wbryant.com> To: cnc-list@cnc-list.com Subject: Re: Stus-List New Head and holding tank system. Date: Tue, 22 Oct 2013 22:22:25 +0000 Martin wrote: > All output of the head goes directly into the holding tank. From there we > can pump out at a dock or use a macerator type pump overboard. We put in two > vents, one each side of the boat to be sure the KO brand (now sold by > Raritan) holding tank treatment had plenty of air. In over 10 years of often > heavy use there has been little to no smell and only one "failure to contain" > event when the red warning light was ignored by a post-race delivery crew. I set mine up this way as well, to minimize the amount of hose used. Although I planned for plumbing direct overboard discharge, and have the parts and fittings on board, I've never done it. One important observation: Women with long hair can really jam up a macerator pump. Men shed hair just as fast as women do, but we tend to have shorter hair. If your head is also the shower, hair will get in there and end up in the holding tank. One 16" strand of hair, if wrapped around a motor shaft, is incredibly strong. Frankly, before I'll let another woman sail with me for any length of time, I'll insist that she let me tie her down and shave her. Or go get her hair cut short. HIGH PRIORITY INFO. I am *incredibly* glad that I used the expensive shields head hose fittings, which are not barbed but are long enough for multiple hose clamps, because I have taken that pump off about every four to six months and cleaned it out. I smear the smooth hose fittings with silicone paste before reinstalling the pump, because I know I'll be back. I replaced the pump, and keep a spare on board, but have learned some things: 1) The macerator pump makes three sounds -- a) priming b) pumping c) gulping air and pumping it out the bottom of the boat. I used to listen to air bubbling to make sure my tank was empty, but learned that that also sucks the sludge and hair from the bottom of the tank and fouls the pump. Now I listen carefully, and note that there's actually a '2-3/4' sound just before the pump starts gulping air, and I flip the switch. When I get to a good pump out station, I'll have someone hold the pump on the deck fitting and flush the tank out with a hose from the inside, trying to work as much sludge into the outflow as possible. Then I remove the latex gloves and take a shower. 2) Multiple vents are cool, but think about how air will flow in and out of the tank under various points of sail. I added a second vent, but when the breeze is about 30 degrees off my starboard bow it comes in one vent and out the other and right into the cockpit. That's usually when I go below to study the charts. <G> If I had to do it again, I'd use the same design but use an expensive diaphragm black water pump, that are like the manual cockpit bilge pumps but electric. Heck, I would have paid for one twice over the the amount of parts and time I've spent nursing (sic) clogged macerator pumps. Why macerate, anyway? I insist that nothing go into the head unless it has passed through the body. Yes, the macerator can handle toilet paper. However, many people are confused about what that means. 'Wet Ones' are not toilet paper. Paper towels are not toilet paper. Tampons are not toilet paper. Corn cobs are not toilet paper. Wal _______________________________________________ This List is provided by the C&C Photo Album http://www.cncphotoalbum.com CnC-List@cnc-list.com _______________________________________________ This List is provided by the C&C Photo Album http://www.cncphotoalbum.com CnC-List@cnc-list.com _______________________________________________ This List is provided by the C&C Photo Album http://www.cncphotoalbum.com CnC-List@cnc-list.com
