Catalina 27 Sanitation Upgrade

Oct 18, 2013
20
Catalina 27 Vernon, BC (Okanagan Lake)
Hi All.

I am preparing to do a sanitation system upgrade and I would like the benefit of the experience of others:

1) Has anyone installed vented loops between the toilet and holding tank, and between the toilet and flushing pump outlet? This is what is recommended in everything I have read so far.

2) I am thinking of replacing the hoses with PVC pipe wherever I can, making sure there is some hose used to provide strain relief for the rigid PVC pipe. Has anyone tried this?

Any comments would be appreciated.

Thank you,
Trevor
 
Aug 1, 2011
3,972
Catalina 270 255 Wabamun. Welcome to the marina
Adding flex pipe to rigid pipe at each end requires 2 more hose clamps per joint, and that many more places for failure, and leakage. Why not just use proper sanitation hose? This seems like a lot of extra work.
 
Oct 18, 2013
20
Catalina 27 Vernon, BC (Okanagan Lake)
Valid question Meriachee. Thank you.

I have 2 prinipal reasons:

1) To reduce the amount of hose that will inevitably permeate and need replacing. My new design will also have the same number of hose clamping interfaces as my current system.

2) To redesign the system so that there is never any waste sitting in the hoses, which I think is a deficiency in how my current system has been installed.
 
Dec 2, 1997
8,709
- - LIttle Rock
Whether you need a loop--vented or maybe not--in the line between the toilet and tank depends on two things: distance from toilet to tank and whether it's an uphill run from toilet to tank. You definitely need a VENTED loop if the toilet is plumbed to also flush directly overboard at sea.
A vented loop in the intake, installed between the pump and the bowl, is needed if the toilet bowl or any part of it is at or below the waterline. It needs to be at least 6-8" above waterline at ANY angle of heel, not just when the boat is at rest...which on most sailboats puts 2-3 FEET above the bowl.
Hard pvc is ok for long straight runs, but there aren't likely be any on a 27' boat that are long enough for it make sense when you have to use about a foot of hose to "soft couple" the connections to anything rigid (toilet, tank, thru-hull) to protect the pipe from stress and flexing that can crack it. Although they aren't cheap, there are two hoses that won't permeate---Trident 101/102 (identical except color...101 is black, 102 is white) Trident #101 Sanitation Hose ...and Raritan Saniflex Raritan SaniFlex hose . Trident 101/102 is a double walled rubber hose...it has only one drawback: it's as stiff as an ironing board, making it necessary to insert inline radius fittings if it has to bend much tighter than hard pipe can bend. Raritan Saniflex is considerably more expensive, but can be bent like a hair pin without kinking.
Unless you're determined to keep a "real" marine toilet and lose at least 1/4 of your storage space to the tank and related plumbing, you might want to consider replacing the whole system with a self-contained contained system...


On any boat much smaller than about 28', a self-contained system—an "MSD" portapotty-- makes a lot of sense. The "MSD" designation in the model name/number means it has fittings for a pumpout line and vent line, and is designed to be permanently installed (actually just sturdier brackets than portables, so you could still take it off the boat if you absolutely have to), which means that although it's still called a PORTApotty, you don't have to carry anything off the boat to empty it.
A 5-6 gallon model holds 50-60 flushes...you'd need at least a 30 gal tank to hold that many from a manual marine toilet. No plumbing needed except a vent line and pumpout hose--so no new holes in the boat...and -0- maintenance needed except for rinsing out the tank--which you can do with a bucket while it's being pumped out. Total cost including the pumpout hose and vent line is about $200--a fraction of what you'd spend for toilet, tank and all the related plumbing needed. And the best part is, you have all the advantages of a toilet and holding tank without giving up a single square foot of storage space.
Think about it....
If you'd like some one-on-one help deciding what to do and how to do it right, you're welcome to give me a shout via PM. You might also consider checking out my newest book (see link in my signature)...it's a comprehensive marine toilets and holding tanks 101 manual that even includes step by step installation instructions.
 
Oct 18, 2013
20
Catalina 27 Vernon, BC (Okanagan Lake)
Hi Peggy. I have your book and have talked to you in person at the Oakland/Richmond sailboat show and I believe I am following the advice you gave me. I have already replaced the puny (and completely blocked) holding tank vent with a 3/4" thru-hull to get air to the good aerobic bacteria.

The whole toilet is below the water line. I have a seawater inlet for flushing and therefore need a vented loop between the outlet of the toilet hand pump and the toilet bowl that is long enough to be well above the waterline when heeled over.

The outlet from the toilet is well below the holding tank when heeled over, and I currently have a recurring issue of waste siphoning back to fill the toilet bowl when heeled over, even with an almost perfectly molded joker valve. I therefore need a vented loop between the toilet and tank that is long enough to be well above the tank when heeled over.

The two vented loops do take up a lot of space on the head wall and are not that nice to look at, but I believe they are both necessary. The holding tank is also plumbed to empty directly overboard, via a Y-valve, a macerator, and a seacock when out at sea.

The existing hose from the tank outlet to the pumpout fitting is 6 feet long, but most of it runs along the keel and below the level of waste in the holding tank; i.e. as the tank fills with waste the hose fills with waste. I am changing this to a PVC pipe that goes vertically from the tank outlet to above the top of the tank and then horizontally to just below the pumpout fitting; in this way the waste is sitting in the vertical PVC pipe and not a hose. Then I have a foot of hose running vertically from the PVC pipe to the pumpot fitting as a strain relief for the rigid PVC.

I am using the best hose I can buy. For the 1 1/2" runs I am using Shields 105 PolyX sanitation hose at $25/foot. For the 3/4" runs I am using Vetus sanitation Hose.

I wish I had known about the "MSD portapotty" before I started this project, but I am too far in with time and money to change plans. But, if my new system doesn't pass my wife's "smell test" I will be getting one.

Thank you,
Trevor
 
Oct 18, 2013
20
Catalina 27 Vernon, BC (Okanagan Lake)
Hi Donnybrook.

The holding tank is under the V-berth mounted to the keel. The toilet is immediately aft of the V-berth on the starboard side. The boat is a 1988 Catalina 27.

Thank you,
Trevor
 
Dec 2, 1997
8,709
- - LIttle Rock
I wish I could remember everyone I meet at boat shows, but by the time they're over I'm lucky to remember who I am! Glad you bought my book there...it had just come out and I was there to introduce it. I do remember one thing about that show though: it was rainy and COLD!

The outlet from the toilet is well below the holding tank when heeled over, and I currently have a recurring issue of waste siphoning back to fill the toilet bowl when heeled over, even with an almost perfectly molded joker valve. I therefore need a vented loop between the toilet and tank that is long enough to be well above the tank when heeled over.
You won't need a VENTED loop for this application, just a loop. If you aim the toilet discharge fitting straight up to the loop then down to the tank, you'll only have to pump enough times to push bowl contents over the top of it...gravity will do the rest. You should be able to do this in the dry mode, followed by a second flush of just enough water to rinse out the hose. This will add at least 50% to the number of flushes your tank can hold compared to flushing all the way to the tank in the wet mode.

There is another way to prevent waste from spilling into the toilet discharge hose and the vent line without the need for any loops: move the fittings in the tank...which is actually very easy to do thanks to a gadget called the Uniseal UNISEAL . Waste can only run into those lines if they're on an OUTboard (closest to the hull) wall--side, end or top . Moving em to the INBOARD (closest to the centerline) side of the same wall makes it impossible because when you heel to one side, tank contents run to the other side...when heeled to the other side, tank contents run uphill. Upgrading the vent fitting to 1" and moving it to the top of the bow end of your tank with the line going forward would make it possible to completely eliminate odor out the vent when you flush. You can seal the existing fittings with threaded plugs wrapped in plenty of Teflon tape.

I am using the best hose I can buy. For the 1 1/2" runs I am using Shields 105 PolyX sanitation hose at $25/foot. For the 3/4" runs I am using Vetus sanitation Hose
I hope you haven't already bought it 'cuz Shields Poly X is no better than Trident 101 (about $8/foot) and Raritan SaniFlex, which, according to Practical Sailor, is the most flexible hose runs $11-12 most places. Both can be bought by the foot.

The offer of one-on-help will remain open permanently.
 

weinie

.
Sep 6, 2010
1,297
Jeanneau 349 port washington, ny
my old 27.

This loop was to keep sea water from flowing into the bowl. The electric jabsco didnt have a water/air switch like the non electric one, so sea water would fill the bowl when heeled.
Keep the waste out was solved by simply twisting the pvc elbow in the right direction so it had to flow a bit uphill from the tank.
 

Attachments

Nov 8, 2007
1,523
Hunter 27_75-84 Sandusky Harbor Marina, Ohio
I want to affirm the MSD/portapotty solution Peggy suggested. We have one on our Hunter 27. We have cruised over 7,000 miles, and anchor out or moor whenever we can. We pump out like a toilet/holding tank system. With consistent use of Odorlos, we never have an odor problem. And the capacity is great - far better than the holding tank systems we have chartered.

Give it some real consideration - better performance with a much simpler system and lower cost!
 
Dec 2, 1997
8,709
- - LIttle Rock
The electric jabsco didnt have a water/air switch like the non electric one,
Relying on the "water air switch" (wet/dry valve) to keep water out of the bowl is very risky because a) water usually doesn't just fill the bowl, it overflows it....b) wet/dry valves fail and...c) people forget all too often to switch to dry after using the toilet. If you're lucky enough to be aboard and awake to notice that your shoes are afloat in the cabin in time to switch the valve to dry, you only have a mess to mop up. But more than one person has had to get up in the middle of the night and stepped out of his berth into calf deep water and a lot more boats have gone down in their slips when no one is aboard. Which is why the installation instructions (which too many people don't seem to think they need to read) for every manual and most electric toilets specify a vented loop in the intake (see the 2nd paragraph in post #4 above for the correct location). If your electric toilet is one that doesn't have a line connecting the pump to the back of the bowl, it's necessary to install it in the line from the thru-hull to the pump. That requires an electric solenoid valve wired to the flush button.

Jabsco 37068-2000 vented loop with solenoid valve.jpg
 
Oct 18, 2013
20
Catalina 27 Vernon, BC (Okanagan Lake)
Hi David in Sandusky,

Could you please tell me(us) the brand and model of the MSD portapotty that you are having success with?

Thank you, Trevor
 
Dec 2, 1997
8,709
- - LIttle Rock
If his is more than a few years old, the same model # isn't likely to still be available. The only two 5 gallon MSD potties available in the US are the SeaLand 975MSD (the 965 is the previous version...may still be available) and the Thetford 550P MSD.