Waste Y Valve....

[NYSail]

So the first winter project this year will be converting my forward head to a gravity discharge. I have a fresh water flush electric jabsco head.... Currently I have a deck pump out from the bottom of the tank. The over board pump via the macerator comes off the top of the tank with an internal PVC pipe leading to the bottom and its own thru hull/valve. My current Y valve directs waste overboard directly (another thru hull/valve) or to the tank. What I would like to do is get rid of the macerator thru hull and tank fitting..... plumb all waste to go into tank then have a y valve off the bottom that would be for gravity discharge or deck pump out. One less hole in the boat and a bunch of room under the sink (no more hoses and macerator pump). I see some set-ups where they just put a T fitting.... But I think having a lockable Y valve would be more prudent and make the CG happier it I ever get boarded and checked (I think).
Question: what is the preferred Y valve for sanitation.... I see Forespar and Raritan.

Thanks

Greg

 

[Peggie Hall HeadMistress]

I would move the pumpout line to the fitting on the top of the tank and use the one at the bottom of the tank to discharge overboard...eliminating the need for a y-valve altogether. That should leave you with only one thru-hull, no tee.

About gravity discharge: The entire tank has to be above the waterline for it to work. If any portion of the tank is below water, sea water will flood the tank to the waterline when the thru-hull is open...and that pressure will prevent the tank from emptying.
If we need to discuss the pros and cons of the mods you want to make, and what might work better, in more detail than is practical in a discussion forum, send me a PM that includes your email address and we can work out a mutually agreeable day/time to talk about it.

--Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein

 

[NYSail]

Thanks Peggie!
Yes tank is fully above waterline by at least 6”. I didn’t know about regulations regarding overboard discharge, that’s why I thought Y valve with lock for overboard. do I have to lock the seacock closed as with a zip tie??

As always......
Thanks!

Greg

 

[Peggie Hall HeadMistress]

The regs require
(1) Closing each valve leading to an overboard discharge and removing the handle;
(2) Padlocking each valve leading to an overboard discharge in the closed position; or
(3) Using a non-releasable wire-tie to hold each valve leading to an overboard discharge in the closed position.
but a plastic tie wrap through the handle is enough to satisfy the regs. Just don't leave scissors or a box knife out in the open near it. You DO know that you'd need to be in open sea at least 3 miles from the nearest point on the whole US coastline (which would be 3 miles south Montauk) to dump the tank?

For the system to work properly, the overboard discharge tank fitting really should be ON the bottom of the tank instead of at the bottom of it. With it on the end or a side, waste can't just pass through the tank at sea. Moving it to the bottom would be a fairly easy job using a Uniseal UNISEAL but the Uniseal really isn't recommended for fittings at or on the bottom of a tank. To do it right you'd need to find a plastics fabricator who can spinweld a new fitting. A threaded plug wrapped in plenty of teflon tape will seal the existing fitting.

--Peggie

 

[NYSail]

Thanks so much Peggie! Beneteau actually has great waste tanks....... center discharge with a small sump so everything in tank goes down...... (wish they were as thoughtful with the electrical system). The fitting on the bottom is a 90 degree fitting that is sealed nicely. I replaced all hoses last season with Raritan saniflex.

Greg

 

[NYSail]

 

[Gunni]

It is really, really important that you valve off any tank effluent at the tank and not allow waste to sit in your overboard discharge hose. A simple y-valve on your tank bottom discharge hose will allow you to select deck pumpout or gravity drain to thru-hull. You will need to find an accessible place to locate the y-valve. Alternatively you would need to remove the tank cover to get at it. Which wouldn’t be too bad since once you empty your tank you close it off again and turn your other y-valve and direct discharge the head until you return near-shore.

 

[Stu Jackson]

Greg, are you in a position to defer that decision about the thru hull? Can you install the tank and try it out first before you make hard-to-reverse decisions?
I know how gravity works (imagine...!!!), but you may want to consider testing it out before you commit to eliminating your "backup" pump.
Good luck, either way.

 

[Terry Cox]

Very pleased with our setup. No wye valve involved, just a wye fitting. Everything from both heads goes to the waste tank, which is below the water line. From there I can choose to either pump out through the deck fitting or use the macerator pump to discharge overboard where legal. Simple and effective.

 

[NYSail]

I just spoke with an owner of a French built 2005 (mine is South Carolina). She said hers is gravity from the factory just like Peggie said to do it with no y valves.... bottom of tank to discharge, top to deck pump out.
Gunni that was my thought with y valve.... wonder if I could find just a simple in line valve for that.....
Stu I think I will keep things in place until I’m sure..... thanks!

Greg

 

[Gunni]

The French boats of that era were set up for overboard discharge and had to be re-plumbed to meet U.S. regulations. Boatyards were putting all kinds of systems in. Unless you valve off the bottom discharge in the tank the entire section of hose that extends from the tank to the thru-hull will sit full of waste. Not good.

Forespar sells large diameter marelon ball valves, but you will still need to pull your tank cover off to operate it, or get creative with an access port in the panel.

 

[Peggie Hall HeadMistress]

If you switch the deck pumpout line to the fitting on the top of the tank, a simple shutoff valve that threads into the bottom tank fitting is all you need...and a good idea until you head out to sea and can keep the thru-hull open. 'Cuz sludge will pack the line to a closed thru-hull. I'd also recommend that you use No-Flex Digester as your tank product...it not only does an excellent job of preventing odor out the vent, it also "eats" sludge.
And speaking of the tank vent, we haven't discussed what you may need to do about it to make sure it can provide enough oxygen to the tank to keep it aerobic and prevent vent blockages.

--Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein

 

[Bob S]

Greg,
I hope you take pictures. I bought a diaphragm pump to replace a failed macerator but it's too big to fit in the forward head. I've had the bulkhead off my aft head but really didn't scrutinize the set up. I'm sure it's the same as your picture. Looks like there is a 90° fitting at the bottom which in my Pullman berth would make sense as it goes to a port thru hull. Are you planning on using one of the existing thru hulls? Wouldn't the section of hose below the waterline always be filled with effluence? I'm thinking of doing a similar set up so I'll be following this thread. I don't know how you can put a ball valve at the bottom and have any kind of easy access.
Bob

 

[NYSail]

Once I remove all the ancillary hoses associated with the Macerator I will be able to reach through the cabinet to the bottom of the tank to operate a valve..... I like the idea of an inline valve at the bottom of the tank. I will snap some pictures..... I have the tank out and in my back yard now..... nice and clean! I am also taking the opportunity to replace all thru hull valves and skin fittings..... Beneteau used brass and no backing plates. Very tight fit! I will be removing the macerator valve as part of this also.

Regarding my vent, I have not measured but think it’s 1/2 inch out to the side with your typical waste vent fixture. I use Raritan K.O. And have no issues with odors..... but would make sense to enlarge vent to allow gravity discharge work better.
Again thanks all for the great input!

Greg

 

[Terry Cox]

Beneteau used brass and no backing plates

All of our through hulls have backing plates, a quality move by Hunter.

 

[Bob S]

I wish I were retired so I could do all the things I'd like to! I planned on replacing the failed macerator with a diaphragm pump but I like your approach better.

 

[Gunni]

You have such nice clean bilges! Those are bronze thru hulls, the valve is brass with zinc plate. Great news on euro-thru hulls, GROCO is now making BSPP threaded fittings which are compatible with the bronze fitting straight thread. GROCO valves are a big improvement, stronger, bronze, no hollow balls, etc.

You DO have backing plates, you may not think they are robust enough but the fitting is backed. Hard to justify more robust construction in a protected area like that. Isn’t like something heavy is going to sheer it off.

 

[NYSail]

Yes the area under sink is well protected..... will be hard to work in there but I will manage....... Thanks.... I love a clean dry bilge... makes for a sweet smelling boat.
And yes.... nice to see the new groco comparable valves. I already had to replace one. However I will be replacing skin fittings as well from now on...... like to know they are new.....
Greg