Poor venting by design

Aug 15, 2019
9
Niagara 35 Berkeley
Ok, well it seems my thread got off course while I wasn't looking. Back to it. Hope ya'll didn't scare Peggie away!

I just got my "new" boat back after a month of being in the yard -- during which time I stayed aboard my prior, now-for-sale boat which reminded me how fresh smelling a boat can be, particularly when it has exceedingly short sewage hose runs and no low spots.

Anyway, after all the fixes with the vent line, tank inspection port, and a (mostly) deep cleaning, the "new" boat stinks even worse than I remembered when I left it at the yard. Two nights ago I removed as many removable parts around the tank and hoses as I could, did a couple rounds of soaking, scrubbing, and spraying the bilges, hoses, tank and surrounding surfaces with diluted ammonia and baking soda, and then sprayed everything with a white vinegar solution (honestly not sure how I came up with this cleaning regimen).

Last night, after all that had dried out, the odor was still there. On my hands & knees sniffing around like a dog, all signs point to permeated hose(s). I'm going to get clean rags and do the rag test tonight. Mind you, this is 5 month old Trident 101 for the in/out, which was still wrapped in plastic when I walked it out of the chandlery, and it still had that new-hose rubber smell upon installation. Vent hose was also brand new Trident Vac XHD.

I know Peggie's book mentions hose as new as 3 months getting permeated, and with my luck, I won't be surprised if I got a bad batch of Trident. Still, really disheartening.

Questions:

(1) Has anyone ever pursued the Trident "10 year warranty" claim? How does that even work, do you send them a sample of the hose(!)? Was there a warranty card I was supposed to fill out when I bought it?

(2) I know I should be able to rely on quality sanitation hose as I have in the past. But frankly I'm fed up and don't want to repeat the exercise of muscling new hose in place and gambling another $600 in the process.
Assuming it is the outlet hose with standing sewage that is permeated, I'm planning to replace that part with PVC pipe. Any tips or examples of doing PVC for marine sanitation appreciated. I've never worked with PVC before but have to imagine it's more fun to measure, saw, and glue than it is to wrangle those %^@#$ hoses. Orders of magnitude cheaper, too, so I can screw up all I want until I get it right.

(3) A quick look at Home Despot shows most 1.5" PVC elbows & such are rated for 5 psi. That seems problematically low. Is there a particular category or type of PVC pipe and fittings one works with in marine sanitation?
 
Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
Assuming it is the outlet hose with standing sewage that is permeated, I'm planning to replace that part with PVC pipe. Any tips or examples of doing PVC for marine sanitation appreciated.
A quick look at Home Despot shows most 1.5" PVC elbows & such are rated for 5 psi. That seems problematically low. Is there a particular category or type of PVC pipe and fittings one works with in marine sanitation?
There are 2 grades of PVC, one is for drains in a house and the walls of the pipe are thinner. Another grade of PVC is designed for pressurized water and the walls are thicker. This is also the type of PVC the is used for PVC furniture and projects around the home. They are known by their "schedules" one is Schedule 40 and one is Schedule 80. I can never remember which is which, but the difference in obvious.

PVC pipe can be used for some of the run. The issue with rigid piping on a boat is that a boat moves and flexes so the plumbing must move and flex also. This can be addressed by inserting short sections of hose at critical locations where the flexing might occur. A couple of other issues are the fittings into the tank, are they tapered (NPT) or straight (NPS). Another is the 90° elbows. There are 2 types of elbows, sweeps and 90° elbows. The sweeps turn 90° over a fairly large radius, regular elbows turn 90° in the diameter of the pipe. The sweeps are better for sewage as they are less prone to clogging.

If you look on the Sailing Uma YouTube channel you can find some videos of Dan installing PVC pipes for their sanitation and fresh water systems.

After ventilation and good quality hoses, rerouting the tank outlet from the bottom of the tank to the top with a dip tube is the best solution. In this arrangement there is no sewage sitting in a hose permeating it. I did this on my old boat, a Sabre 30. Here's a link to the description:

 
Mar 20, 2016
594
Beneteau 351 WYC Whitby
Back to Ozone I can tell you hands down it works and the odors do not come back. I purchased one off ebay , a cat went into my car thru the open sun roof and sprayed into the car . The car was steam cleaned several times and the odor left ,however every time it rained or was damp out the smell would come back for over 5 years. I did an ozone treatment and the smell has never come back and it's been over a year. I have also used it on my boat as have many others for odors and diesel spills , and they are gone and do not come back. There are real estate agents that use them to sale pet and smoked in houses . Most car dealerships use them to sale smoked in cars.My buddy is an HVAC guy he goes into houses where people smoke and the house ranks and goes into others that have a honeywelll air cleaner and there is no smell , yes air cleaners produce ozone to kill the smell
 
Aug 15, 2019
9
Niagara 35 Berkeley
After ventilation and good quality hoses, rerouting the tank outlet from the bottom of the tank to the top with a dip tube is the best solution. In this arrangement there is no sewage sitting in a hose permeating it. I did this on my old boat, a Sabre 30. Here's a link to the description:
Great write-up on your site! I had forgotten about those Uniseals, which came as part the dip-tube kit I used on my last boat. I may indeed do belt-and-suspenders, and route PVC piping up to a dip-tube instead of straight out the existing fitting. Going to dig up the specs for my tank now. The discharge route makes a number of twists and turns so I'll have to figure out how to brace the PVC properly, but I'd still rather do that than deal with hose again.
I remember watching Sailing Uma's Rube Goldberg-ian PVC projects and thinking "WTF is he doing? Just use hose like the rest of us and replace it every 5-10 years. Uma's bilge looks like a labyrinth!". I hate to admit it, but Dan proves me wrong almost every time that I think I, with 15 years of projects on 3 boats, know better than him. His obsession with PVC in particular is proving justifiable.


Now I'm learning. There are all kinds of PVC for all kinds of applications, including non-pressurized ones.

330 psi for this small elbow:

....but only 5 PSI for this one:
 

Mr Fox

.
Aug 31, 2017
204
Marshall 22 Portland, ME
I personally would not use PVC. Peggie now recommends Raritan Saniflex hose which had been in use for over a decade with zero reported permeation issues. It’s also flexible so install is easy as opposed to the Trident. I would be looking at other sources of odor if the hose is new.

PVC is prone to vibration damage if mounted solidly to any part of the boat or allowed to contact anything hard. It can crack if something shifts on to it. It will most likely require several joints to conform to the shape you need, which introduces potential leak/failure points. In my opinion trying to measure, cut, glue and install a product designed to be straight is not any fun on a boat.

Hose, however, can be routed easily though bulkheads and along curved hulls with no need for support as vibration is not an issue. Hose will not be cracked by something shifting on to it.

Also in a pvc setup you will need hose anyhow at some tricky curve and/or at the ends (at minimum doubling the amount of hose to pipe connections) which begs the question why not just one length of hose?
 
Dec 2, 1997
8,709
- - LIttle Rock
Are you 100% certain you used Trident 101 Trident has several sanitation hoses...101 and 102 (identical except for color...101 is black, 102 has a white skin on it) have proven to be 100% resistant to odor permeation...but there's also 140 , which is better than 148 but not "bullet proof."

If you really did use 101/102, it's not the source of your odor. If you want some 0ne-on-one help to find the source, send me a PM and we'll find a mutually convenient day/approx time to actually TALK instead of type.

--Peggie
 
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Aug 15, 2019
9
Niagara 35 Berkeley
Okay, I admit I'm lazy and just call it 101 cuz everyone knows what that is! It's actually 102. The green stripe got smudged by the ammonia cleaning. I really don't want to believe it either, but it just failed the rag test, twice to be sure. I soaked some brand new microfiber cloths in warm water. Draped them over the bits of hose you see in the pic, which are the low spots in the system. One at a time. Was careful not to let the rags touch the hoses I wasn't testing.
The top hose is the 148 vent line, middle is the tank outflow, bottom is the inflow. I also rag tested the outflow hose higher up toward the deck fitting, well above the tank level, and it had no odor, just mild rubber smell like the inflow hose.
Peggie, sending a PM now.

IMG_0203.jpg
 

Mr Fox

.
Aug 31, 2017
204
Marshall 22 Portland, ME
Peggie will steer you right, her advice and her book have me helped numerous times. You’re on your way to odor free.
 
Dec 2, 1997
8,709
- - LIttle Rock
If you didn't thoroughly clean and also treat with PureAyre according to directions, there's a good chance that the odor you picked up on the rag could be residual odor left from previous stinky hoses that's attached itself to the outside of the hose and every other surface in that area. And there's another possibility: the white "skin" on 102 can outgas a chemical odor when it's new. Really annoying but it does go away in a relatively short time.

All of which is the reason why I'll want a good description of the "character" of the odor you picked up on the rag....sharp/chemical, soft sewer-like or swampy...when we talk.

--Peggie