When you say "When, if ever, have you rinsed out the tank"
I am lead to ask two questions:
1) How often do you think this needs to be done? 2) What do you mean
by rinsed out?
At each pump out, I pump out, then fill the tank with a few gallons
of water, then pump out again. If I feel like it, I do that twice. Is
that enough, or are you suggesting filling the tank, going for a sail
to slosh it up and then pumping out?
That's enough most times--and good on ya...'cuz most people don't ever
bother to do that much. Only other thing I'd recommend is, a few times
a season it should be repeated until what's being pumped out is just
clean water.
I REALLY do not want to have to open the tank inspection ports, so
anything I can do to minimize the possibility I will do! I do not use
chemicals in the head. I did, but found that it was a never ending
cycle of adding more blue liquid to mask the smell.
Instead, I use a powder made for septic systems that grows a bacteria
of some sort in the tank.
You're on the right track by avoiding chemicals...but septic tank
enzymes are cultured for use in anaerobic systems--holding tanks have to
be aerobic to prevent odor. If the septic tank enzymes were really
working in the tank, you wouldn't have any odor when you pump out. That
means the waste in your tank still stinks.
Since I started using this powder the head has exhibited almost no
smell. That is except when I get a pump out. After a pump out the
whole boat just REEKS. I figured out why just recently. I believe
that the pump out empties the hose to the head too, and in so doing,
opens a direct path to allow the tank vapors to enter the cabin. Only
reason I think so is because I can remove the smell by pumping a
cupfull of water into the head.
All that's doing is providing a water barrier to prevent the odor from
the tank from escaping into the boat. Pumping out should not pull air
through the head...that's an indication that the tank vent isn't
allowing enough air into the tank to replace the waste being pulled out
by the pump out. That may be due to a partially blocked vent, or it may
be due to a vent line that's too long and has too many bends in it...a
vent thru-hull in which the opening is too small (or at least partially
blocked), or vent line that has too small a diameter vs. a particularly
powerful pumpout.
Even so, odor shouldn't be able to escape through the head--the pumpout
is PULLING air into it, not pushing it out. That leads me to believe the
joker valve in the toilet is worn out...that it no longer closes.
Oxygen is the key to eliminating holding tank odor. When waste--or any
other organic matter--breaks down aerobically (oxygenated), the gasses
produced are odorless...but when it breaks down ANaerobically (without
oxygen), it produces foul smelling sulphurous gasses. So the solution to
your tank odor is increased ventilation to the tank. Investigate all the
things I mentioned above and correct what you can. I'd also recommend
that you switch from the stuff you're currently using to a product
called Odorlos. It's a Norwegian import, available at most marine
stores...the active ingredient is nitrates that promote oxygen release
from the waste itself. You can check it out on their website at
http://www. odorlos.com
Anyway, just wanted to ask my questions. Thanks for all the advice I
have read over the years here. You really have helped a lot of folks
by sharing your knowledge!
Always glad to help.
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/html/get_ri...oat_odors.html
Peggie Hall wrote:
WF wrote:
I'd be interested in views as to whether a macerator pump should
be installed higher than the holding tank.
Within the limits set by the macerator mfr, yes...it can be.
Background: On my boat, the macerator (Jabsco) is installed on
top of the waste tank (about 2 feet high). Although it's
supposedly "self-priming", it only functioned if the tank was
completely full, and then it would only take out a gallon or two.
Ultimately, the impeller self-destructed.
That sounds like a blocked tank vent causing the pump to pull a
vacuum, not a problem with the macerator location. Or a blockage in
the tank discharge line. When, if ever, have you rinsed out the
tank to get rid of sludge accumulation on the bottom of it? 'Cuz
macerators aren't that powerful..a hoseful of sludge that can't
make it through the pump can stop one cold.
Armed with a new impeller, I am now considering installing it at
the same level as the base of the holding tank. I'd think it
would then be more likely to prime, and actually pump.
Moving the macerator might extend the life of the impeller a little
by cutting the time it takes to prime from 2-3 seconds to 1...but I
don't think the current location is the problem.
The only down-side I see is that it would be constantly "loaded"
with waste (unlike now, where the residual waste presumably
drains back down the hose to the tank level). But if the pump
seals are good, I figure that's not a problem?
That problem can easily be solved--and should be--by putting a
y-valve in the tank discharge line instead of only a tee fitting.
I say "should be" because macerators never fail when a tank is
empty...you need to be able to cut off the flow of waste to the
pump to work on it.
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/html/get_ri...oat_odors.html
Am I missing anything?
I'd appreciate any views.