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PEEE UUU

Posted: Thu Sep 03, 2015 5:02 pm
by Jimmy
While out boating with friends a few weeks ago, someone (me) had to use the head. While others were enjoying dinner on the back deck, I of course did the polite thing and flushed the vacuflush system. I immediatly heard what sounded like someone had fallen overboard, screaming, cursing, and a panic in all voices heard. After washing my hands, and hurrying out to see what all the commotion was about, I was met with more cursing and finger pointing with only one hand while the other fingers were used to plug the noses of the pointers. Apparently the vent for the holding tank was positioned perfectly with the prevailing winds to flood the whole deck with a giant boat fart. Now, I did my due diligence and being the polite boater, pour about a gallon of treatment into the head about 2 months ago.

It didnt work......

What is the trick to keep the boat from "farting" everytime someone uses the head..... ?

Re: PEEE UUU

Posted: Thu Sep 03, 2015 7:23 pm
by prowlersfish
Pump the tank more often and use fresh water to flush .

Re: PEEE UUU

Posted: Thu Sep 03, 2015 7:48 pm
by jimbo36
2 months ago? really? No head treatment will last 2 months dude. That tank needs a good pump and flush weekly, particularly in hot weather. :shock: Seriously!

Re: PEEE UUU

Posted: Thu Sep 03, 2015 10:30 pm
by captainmaniac
Thanks for this thread! I needed a good laugh! Boat Farts - sounds like something from the Simpsons :lol: :lol:

Re: PEEE UUU

Posted: Thu Sep 03, 2015 10:35 pm
by Jimmy
Lol well, that is why I asked. My other boat had a portapottie, and that would last the whole summer, and never had any issues. This is the first holding tank experience. Read the manual, and not real clear about frequency of pumping. With such a large tank, didn't figure a weekly pump out was needed. Nobody poops that much....

So, off to the pump out we go. And yes, fresh water is used.

Thanks for the info. Thought we were gonna have to re-name the boat......

Re: PEEE UUU

Posted: Thu Sep 03, 2015 11:12 pm
by captainmaniac
The system in my F32 is old school, original, recirculating Monomatic head. That means the head is it's own holding tank (like a porta potty), but I can pump contents to a holding tank under the v-berth.

Head holds about 5 gallons - but that is 5 gallons of waste + fluid for flushing. We can use it for a while (with chemical) before it gets too odoriferous, then I transfer to holding tank, recharge the head, and we are good for a while again. Holding tank can handle 4 transfers from the head, before I need to get a pumpout.

Here is a the big difference : with the portapotty and my system, fluids in the system (ick) are used for flushing. So I charge it with 3 gallons or so of fresh water, a bunch of toilet chem, and use it for a few weeks, but only consume 5 gallons of holding tank space as a result.

With the vacuflush, you are using NEW fresh water on every flush (unless dry flush). Waste plus however much water is needed per flush is added to the holding tank on every flush.

Vacuflush isn't as bad as some mechanical heads that use a LOT more water. Looking at some specs for a Dometic macerator head : Normal Flush 0.6 gallons; Low Flush 0.17 gallons. 20 gallon holding tank will be full after about 30 flushes on 'normal', or 100 flushes on Low. Looking at some specs for a Dometic Vacuflush head : Normal Flush 0.33 gallons; Low Flush 0.10 gallons. 20 gallon holding tank will be full after about 60 flushes on 'normal', or 200 flushes on Low.

How many people use the head? Assume 4-6 times a day per person if really using it (or whatever your reality is). 2 people, 5 days straight, is probable 50 flushes.

I need to upgrade, but at the same time, my 36 year old head system WORKS and I don't have to pump out more than 2-3 times a year... so I hesitate to spend the money to upgrade to vacuflush (head, + piping, + tank, + electrical, + whatever else.... plus newer systems eat fresh water every time they flush, so I will need to top up my tank more).

Re: PEEE UUU

Posted: Thu Sep 03, 2015 11:21 pm
by LandVF36
I have a vacuflush system and put in a 55 gal tank a few years back. Prior to that, I had a 15 gal tank and pumped out weekly and treated with 16 oz of thetford chemicals each time. When I got the 55 gal tank, I started going 2 weeks, then three but talk about the boat farts! Then I figured it out. The tank was not the problem, it was the vacuflush tank. Now, just before we leave the boat for the week, I put 16oz of chemicals in and flush with just a little extra water. That way, the vacuum canister is full of chemicals vs waste for the week while we are gone. First flush when we return on Friday night is just fine and pumps outs every other week, or three, seems to be acceptable.

Re: PEEE UUU

Posted: Fri Sep 04, 2015 4:58 am
by Jimmy
LandVF36, what you describe sounds a bit more realistice than a weekly/biweekly pump. We do not use the head Near as much as most. Marina head is only 300 feet away. Boat rule is (and greatly monitored since the big fart), only use the head when we are out. If I remember correctly, the holding tank is like 100 gallons? Which is why I could not imagine a weekly or even bi weekly pumping was necessary ( maybe twice a year). But,,,,, did not consider the vacuflush holding tank as a potential stinky culprit. I like the simple method of a dose of chems in it before we leave, and one when we arrive.

Thanks for all the advise. Gonna get pumped anyway just to start 'Fresh'.

One positive note on all this, we did find this feature Handy one weekend..... A rather irritating group on a boat dropped the hook a little too close to us.... Kept drifting into us, ( not experienced, and yes, downwind)... A few flushes ( boat farts) and was not long, and we had the bay to ourselves. We must always find the positives in every problem right?

:P

Re: PEEE UUU

Posted: Fri Sep 04, 2015 6:34 am
by prowlersfish
Chemicals/treatment help as does pumping out more often . But I have found the biggest help to this using Fresh water to flush and that's means Fresh water from for water tanks not over board . salt and lake water has micro organisms in the water . when they die they add greatly to the stink .

Re: PEEE UUU

Posted: Fri Sep 04, 2015 8:30 am
by kevinz
We had the same issue with our Vacu-flush. I installed a SeaLand SaniGard holding tank vent filter. Kind of pricey, but my 'boat fart' issue is fixed!

Re: PEEE UUU

Posted: Fri Sep 04, 2015 11:41 am
by Jimmy
Kevinz, hmmm never thought of a filter, I,ll look into that too.

And yes, always fresh clean water in the tank.

Re: PEEE UUU

Posted: Fri Sep 04, 2015 3:43 pm
by jhalb
+ 1 on vent filter. Mine came from Canada and can be refilled so you don't need a new one every couple of years. Easy to install.

Re: PEEE UUU

Posted: Sun Sep 06, 2015 1:48 pm
by comodave
The problem is that your holding tank is not getting enough fresh air. The smell comes from anerobic bacteria. Aerobic bacteris does not smell. By adding air to the tank, the smell will go away and you won't even have to add chemicals. We had a 46' trawler that developed the horrible smell whenever you flushed the head. The type of head does not matter, just when you flush the head the stuff going into the holding tank displaces some air that then goes out of the vent, hence the smell outside. On our trawler we added a Groco Sweet Tank system. I was not thrilled about drilling a 2" hole in the holding tank to install the system, but in the end it only took about an hour to install the system, one of the best improvements that I did to that boat. In 2 hours of the system running, the smell was gone completely and in the next 8 years that we owned the boat, we never put any chemicals in the tank whatsoever. No smell after the Sweet Tank was added.

Adding a vent filter can cause some problems in that they can get clogged if the tank gets too full and stuff sloshes into the vent hose. Also the vents restrict air flow in and out of the tank. If the filter does get plugged up, you might collapse the holding tank when you pump it out. And you have to periodically replace them or replace the filter element.

One way to get more air into the tank is to add a second vent from the opposite side of the boat. That way whichever way the wind is blowing, air will flow through the tank. This is easily done if you are replacing the holding tank, otherwise it is not a lot of fun... I have seen some people building their own Sweet Tank system with fish tank aerators and plumbing the air flow to the bottom of the holding tank so the air bubbles up through the stuff in the holding tank.

Re: PEEE UUU

Posted: Mon Sep 07, 2015 2:33 pm
by Jimmy
Very interesting on the venting of the tank. I am going to do a bit more research on the boat to see what venting it has. All that aside, how often is a realistic tank pump out? Obviously depends on the amount of usage, but consider our average 3-5 uses per week. And that is on the generous side. I think it is 100 gallon tank, not exactly sure.

Always great info.

Re: PEEE UUU

Posted: Mon Sep 07, 2015 6:33 pm
by P-Dogg
My '85 tricab has a 40 gallon tank. 100 gallons of poop weighs 800 pounds give or take. I don't think any manufacturer would plan on anyone hauling around 800 pounds of deadweight, at least for these types of boats.

I second the more air theory, so much so that I put it into practice. I recently replaced my Sealand traveler heads with vacuflush heads. I ended up with an extra hole in my boat where the forward head vented overboard (from the integral holding tank). I added another vent to the holding tank that runs to this extra hole, and (will) add a scoop to catch air and direct it into the tank, thus circulating the air in the headspace while under way or on account of the breeze. I would prefer to aerate the contents instead, but I am too deep in other projects to do so now. I will give a sitrep after I get a chance to try my theory.