outside smell from holding tank

[smitty]

I have a 2007 28 TE newport. The toilet is rarely used but when it is used, I can smell it on the back deck. Does anyone know if there is a filter which needs to be changed. Is there some additive I can add to the tank. I currently add a small bottle of tank deodorant after pumping out. Don't remember the brand. Thanks in advance for any recommendations.

[Nancy]

A filter generally is not recommended for a holding tank as it usually causes more problems than it solves. There are almost no standards in the way the boats are equipped, so you'll have to look under the helm station and see if you can spot a filter. I doubt there is one.

Does your tank get well-rinsed after pumping out? Is the odor still there after pumping out? I've had the best luck with Happy Campers Organic RV Holding Tank Treatment, which I buy on Amazon. I use about 1/2 scoop in our 15 gal. tank.

It's possible that your hoses have permeated and the odor is coming from there. You may be able to tell by wetting a rag with hot water, wringing it out, and wrapping it around the waste hose. Leave it for a minute or so and then see if it smells bad.

[carolmarie]

I don’t totally agree with Nancy. On our 2001 we did install an in line vent filter with good results. In fact, we configured the “L” panel below the trim tab controls so it can be readily removed to replace the char coal charged in line filter. Also, of course, an effective tank deodorizer should be used.
Don.

[Norseman]

So the key to odor control in most tanks is the vent line; it must allow a free exchange of fresh air with the carbon dioxide generated by the sewage. Boat builders, boat owners and boat yard personnel who install holding tanks have always viewed the vent line only as a source of enough air to allow the tank to be pumped out without collapsing and as an exhaust for methane (many even mistakenly believe that methane—which in fact is odorless—to be the source of odor.). Some take the attitude that tanks must inevitably stink, so the thing to do is run that vent line as far from people areas—cockpits, sun decks, etc.—as possible, or make the line as small as possible, or install a filter in it. All of the above actually create the very problem you want to solve.

The above copied from an excellent boat on marine sanitation by Peggy Hall, the Head Mistress.

[Pitou]

I have a 2007 28 TE newport. The toilet is rarely used but when it is used, I can smell it on the back deck. Does anyone know if there is a filter which needs to be changed. Is there some additive I can add to the tank. I currently add a small bottle of tank deodorant after pumping out. Don't remember the brand. Thanks in advance for any recommendations.

You've gotten good and accurate advice from all who have responded above and Peggy Hall, The HeadMistress, has the best advice going. I suggest that every boat owner with a marine head get a copy of her book "The New, Get Rid of Boat Odors" for a thorough understanding of marine sanitation.

There is no production boat builder, including Albin, that brings their marine sanitation systems to the point of where Peggy Hall recommends. Like most sysyems aboard the sanitation system at time of build is purposeful and adequate, but could always use improvement. With Albin and if not a Vacuflush system, vent filters were add ons by owners. With such a small holding tank on the 28's ranging from 6 to 9 plus gallons it doesn't take long for the it to become somewhat full and with only a 5/8" vent line there is no way that there is enough air being introduced to naturally eliminate odor. I would and did add a filter to the 28TE vent line as the vent is right under the starboard sliding window at the mid-ship cleat. When someone used the head and flushed .. guess what the air would get pushed out right under my nose and the odor would more often than not end up in the wheelhouse or in the back deck .. no thanks. It's a simple solution. Remember, the filter does need to be replaced annually and that you are adding a maintenance item. For me a vent is worth it.

For a thorough tank and sensor cleaning .. try NoFlex Digester by Zaal.

Holding Tank Vent Filter.jpg

[Carl]

We have found the most effective practice of keeping the odor to a min is this. Never open the sea cock to the head which allows the introduction of sea water along with sea creatures. We simply use a cup of fresh water from the sink to flush and then rinse the bowl. Ultimately a connection to the fresh water system with a anti siphon valve would be ideal and is on the list for this winter.

[Nancy]

Yes, I completely forgot to talk about the vent line. When we re-did our hoses and holding tank, we installed a 1" vent line. That + Happy Campers = no odor ever. Peggie Hall coached me on the re-design.

[Norseman]

Yes, I completely forgot to talk about the vent line. When we re-did our hoses and holding tank, we installed a 1" vent line. That + Happy Campers = no odor ever. Peggie Hall coached me on the re-design.

Nice: 1” vent line sounds good,
Did you use adapters or reducers at the tank and the vent side, OR did you install new 1” hardware?

[RobS]

I'm thinking Nancy "added" a 1" vent line to now have 2 vents for cross ventilation. Best if the vents are on opposite sides of the hull but either way 2 is the way to go...

[Nancy]

We completely re-did the waste system when we bought the boat. New hoses, new 15-gal. holding tank built to our specs (from Ronco). The existing vent opening was smaller than 1", and we enlarged the hole and put in a new thru-hull fitting. We thought about two vents, Rob, but that was more than we wanted to tackle. One vent is doing the trick.

[Pitou]

Nice job Nancy enlarging your tank capacity as well as the the vent line. I must ask, when you flush and air is displaced from the tank does odor get expelled from the exterior vent?

This spring I replaced all 1 1/2 inch head hose (39 ft.) with Trident 101 and two short pieces of Saniflex where bends were extremely tight on my Vacuflush. I replaced the discharge pump and rebuilt the Vacuum pump. I fell short on doing something different with the 5/8 inch vent line and just replaced it and its filter. I was considering eliminating the vent filter component that Vacuflush uses with the 5/8 inch vent line and replacing it with two - 3/4 inch vent lines as Rob describes on opposite sides of the boat, but ran out of time and I've been feeling like I left the job incomplete and undone and am grateful for this discussion on AOG.

[Nancy]

Hi Kevin - no odor whatsoever when flushing. I really like the Happy Campers deodorizer. It's benign, i.e. no unpronounceable chemicals, never hardens in its plastic jar, and is odorless. Before discovering it, I was using Odorlos, which was good, but this is better.

If the vent at the tank is 5/8", wouldn't you have to re-do that (ugh) to upsize to 3/4" or 1"? Are you having an odor problem? If you ever replace the tank, go with 1" vents then. I'm sold on 1" vent lines. This is what we also had on our Trojan F32. On the 28TE, running a vent line to the other side of the boat would be a huge hassle. I don't regret not doing it, and I'm certain my husband doesn't either!

[Pitou]

Hi Nancy, I do not have an odor problem at all as long as the vent filter cartridge gets replaced annually and I do use Odorlos. I'll have to check out Happy Camper the next time. BTW .. with all new hoses I am a happy camper!

I got into redoing hoses after my discharge pump failed at end of season last fall. The original cheapo hoses that Albin had used had permeated so I jumped right in to redo and improve. I have a Vacuflush system with a 27.5 gallon holding tank and I have no desire or need to replace the tank as it and the sensors are in A+ shape. To redo the vent system which utilizes a charcoal vent filter integrated and strapped to the top of the tank, the tank would need to be removed to enlarge the existing vent hole and to possibly add a second. With my rebuild pretty much now in the rearview mirror, I'm not too excited to delve in again.

I will say that it's nice to hear from someone first hand who has a holding tank without a charcoal vent filter, proper venting and that it actually works as designed. I've always been skeptic!

[Nancy]

Right, Kevin, it would make absolutely no sense to change a working system. Ooo, Vacuflush. We had one on our Trojan, and it worked great after we replaced nearly every component in the system . . . I cringe to say this - the previous owner proudly used Pinesol in the system, and it ruined all the hoses, seals, rubber fittings, etc. Unbelievable. After we got finished replacing all hoses, vacuum tank, vacuum switch, holding tank, rebuilt the pump, and put in that 1" vent line (again only one and no filter), all was good.

[Nancy]

Kevin, I meant to ask you - how did you connect the Trident 101 and the Saniflex? My husband and I were just discussing the possibility of doing that as there's a miserable bend right at the toilet outlet where it turns to go into the the base of the cabinet.