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Wayne.B
 
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Default Peggie Hall question

Thanks again, it's always a pleasure discussing unpleasant subjects
with you. :-)

======================

On Mon, 22 Mar 2004 20:21:46 GMT, Peggie Hall
wrote:

Wayne.B wrote:
I spend quite a bit of time cruising in RI and MA, and occassionally
on the great lakes. Would you put the Y-valve to the holding tank
before or after the Lectra/san?


Raritan prefers that it be after, on the theory that putting treated
waste in the tank is "healthier," but only one bacterium has to survive
and multiply to become zillions in a very short time, so it doesn't
really matter...put it where it's the most accessible.


That also raises the question about through hull fittings. Can
you pipe the output of the holding tank macerator to the same through
hull as the Lectra/san if you use check valves on both sides?


Yep. But I see no reason why you'd need check valves. The L/S discharges
by overflowing out the top, so it's unlikely that waste from the tank
would get into it, especially if you specify all the tank fittings on
the top of the tank, with a tube inside to the bottom on the discharge.
I'd also spec two discharge ports--one for pumpout, one for overboard
discharge. That eliminates a y-valve. And, I strongly recommend that you
go with an electric diaphragm pump--the SeaLand T-series--instead of an
impeller macerator. When impeller pumps aren't used much, the impeller
tends to have a high failure rate...it gets stuck to the inside of the
housing, the stress on the vanes when it's started again often cracks one.

However, in most waters where you'd have to use the tank, you'd prob'ly
have to use a pumpout anyway. In coastal "no discharge" waters where you
can get out to sea beyond the "3 mile limit" to dump the tank, you'll
soon be able to process it through the L/S. That's not possible now, but
Raritan has a system in development they claim should be available by
the end of the year that will make it possible, and can be retrofitted
to installed Lectra/Sans--at least to the current model...I'm not sure
about older ones.