Roger Long wrote:
I just went through Calder's section on head plumbing and it sounds
like a lot of the greater odor of salt water flush over fresh is not
the salt but all the plant and animal stuff that comes in. A
strainer in the intake line sounds important.

A strainer will keep weeds, jellyfish, and other larger sea life from
being sucked into the head intake line and becoming trapped there or in
the channel in the rim of the bowl...but it won't prevent sea water
intake odor. Sea water--especially coastal sea water--is alive with
microscropic animal and vegetable life that die, decay and stink when it
sits and stagnates in the intake line, pump and rim of the bowl.
Flushing all the sea water out, especially at the end of a cruise,
before the boat will sit for several days or longer is the only way to
eliminate it. Just pouring fresh water into the bowl cleans out the
head DISCHARGE line, but it won't rinse out the intake and channel in
the rim of the bowl, because nothing that goes into the bowl is
recirculated through the intake...if it did, waste in the bowl would
recirculate too.

So the only way to get rid of it is by using some means of introducing
clean fresh water into the head intake line--but NOT by connecting
directly to the onboard fresh water system! There's no way to connect
any raw water toilet to the fresh water system without risk of polluting
the potable water supply...and every toilet mfr warns against doing so
in their installation instructions. Only toilets designed by the mfr to
use pressurized flush water should ever be connected to the fresh water
plumbing.

--
Peggie
----------
Peggie Hall
Specializing in marine sanitation since 1987
Author "Get Rid of Boat Odors - A Guide To Marine Sanitation Systems and
Other Sources of Aggravation and Odor"
http://www.seaworthy.com/store/custo...0&cat=6&page=1