Sanitary Systems
I have a small (6 gal) black water tank for the aft head and intend to
replace it with a larger tank. Because the location of the larger tank will
be a short distance from location of the smaller tank I had thought to ask
anyone if I could run the tanks in series rather than remove the smaller
tank completely? I may be over thinking things.
Thanks,
ps: Also, I just finished plumbing in a fuel polishing system for around
six or so hundred. The exact figure will come but got scared by how proud
Gulf Coast and Racor were of their stuff. I used Goldenrod filters and a
Walbro pump. Amazon supplied the fittings.
The feed was taken just before the main filters and the discharge put into
the fuel return.
Vacuum is measured after the filters and backflow preventers isolate the
main plumbing.
I can isolate every failure point and have complete access to the works.
I hope the filters work out but are easily replaced with their more
expensive brethren if necessary.
Its not much to look at but pics can be shared.
--
Tom M Theobald
Further, GB42, Hull #124
tommtheobald@gmail.com
623 640 6130
I would only do this if the connections can be made at the tanks' tops
and not at their bottoms.
Lee
Çanakkale, Turkey
On 10/26/14, Tom Theobald ...
Because the location of the larger tank will
be a short distance from location of the smaller tank I had thought to ask
anyone if I could run the tanks in series rather than remove the smaller
tank completely? ..
On 10/26/2014 02:12 AM, LAL via Trawlers-and-Trawlering wrote:
I would only do this if the connections can be made at the tanks' tops
and not at their bottoms.
You'll have a hard time emptying them that way. You'd need separate
pump-out fittings on deck for each tank, and separate macerators if so
equipped, or else a system of valves to isolate each tank while
pumping/macerating.
FWIW, we have two tanks "in series" due simply to the design of the
boat; there is a large steel bulkhead in the way of making one larger
tank. Our tanks are connected together at their lowest points with 1.5"
sanitation hose, and they also share a common connection to the vent
system above the tanks. The forward head discharges to the forward
tank, and the aft head to the aft tank, but both the pumpout and
macerator lines are connected to the aft tank only. That choice was
dictated by the fact that the bottom of the aft tank is actually
somewhat lower than the bottom of the forward tank.
This arrangement has worked without problems since it was installed over
a year ago.
-Sean
m/y Vector
on the hard in Deltaville, VA
http://OurOdyssey.Blogspot.com
On 10/26/14, Tom Theobald ...
Because the location of the larger tank will
be a short distance from location of the smaller tank I had thought to ask
anyone if I could run the tanks in series rather than remove the smaller
tank completely? ..
And another hint: When installing the discharge, put a goose-neck at the
discharge, kind of like a P-Trap - making sure the top of the bottom loop is
lower than the bottom of the tank. That way you will be able to fully pump
out the tank.
Just taking a fitting directly off the bottom of the tank and up to the pump
out will only allow a vacuum to be maintained (and hence pumping to
continue) until the top of the tank discharge fitting becomes exposed, leave
over 1" of stuff un-pumpable on the bottom of the tank.
Which also brings up a problem with two tanks in series. Assuming each is
vented, and they will not gravity flow from the 1st tank in to the 2nd
(meaning some external pump is needed to push stuff in, and pull stuff out),
there is some issues with venting. If you vent each tank you might only be
able to pump out the last tank, as its vent will prevent a vacuum being
formed to 'suck' things out of the 1st tank. AND when the head pumps things
into the 1st tank, its vents will not allow any 'pressure' built up to
transfer waste into the 2nd tank, it could start going out the overflow.
So, I think there might be some issues with two tanks what are not installed
in a way to gravity feed. Two tanks next to each other on the same 'level'
and connected with a hose at their bottoms and top turns them into effect
one large tank with a baffle in the middle. (ala, like Sean's sounds). But
of the tanks are far apart, and/or on different levels you might think about
how stuff will flow between them when filling and discharging. Creative
valving of the vents could overcome some of these issues, but that just
seems like a problem waiting to happen.
-al-
Viking Star
45' Monk Sr. / McQueen
mvVikingStar.blogspot.com