Head Flush - Raw water vs Fresh water

[HeyJude]

What's your opinion using raw sea water vs fresh water from storage tank to flush?

 

[Larry M]

If you have the fresh water capacity for the head, use it.* You'll cut down on*odors and you won't get the build up on the inside of your discharge lines caused by the urea and salt water mix.

You do have to be careful on the type of head that you have if you are going to convert from salt to fresh.* Check the manufacturer's recommendations.

Maybe we'll hear from the Head Mistress.

 

[jleonard]

I changed both mine to fresh water a couple of years ago. No more smells. Never a problem with capacity as the head really doesn't use that much relatively speaking.

I bought one new raritan Sea Era head and converted the other Jabsco using the same devices that came with the Raritan.

 

[JohnP]

If you are buying new heads, go fresh water.* I had a Raritan FW Marine Elegance head for the past 2 seasons and think it is great!

Odor free and stays clean.* Also nice and quiet.

JohnP***


-- Edited by JohnP on Friday 15th of April 2011 12:52:33 PM

 

[markpierce]

Do you have sufficient fresh-water tankage to convert to fresh-water flush?* What is the typical water usage of a toilet per person anyway?* The Coot has a water capacity of 210 gallons and will be coming with a fresh-water toilet.

 

[HeadMistress]

BON DIA wrote:
What's your opinion using raw sea water vs fresh water from storage tank to flush?

*

*Toilets designed to use fresh water use* less of it...use less power...and are MUCH quieter than toilets designed to use sea water.* And, fresh water eliminates sea water odor problems.*

However, you cannot just decide to connect a sea water toilet to the onboard fresh water supply. That cannot be done without risk of e-coli contamination of the fresh water, damage to the toilet, or both and EVERY toilet mfr specifically warns against it in their installation instructions.* ONLY toilets that are designed by the mfr to use pressurized flush water should ever be connected to the fresh water supply.* If you have a sea water toilet and don't want to replace it, your only option is a water tank that's totally separate from the fresh water system,* including the tank vent and fill.

Fwiw, I highly recommend the Raritan Elegance* Raritan Elegance toilet ...as does everyone who owns one!

Mark, to answer your question...

The average adult uses the toilet 5x/24 hours.* Average flush is .6 gallon...so you need to allow about 3 gallons flush water a day (and that includes VacuFlush if you want to it be trouble free) for each person continuously aboard...or 42 gal/week for a cruising liveaboard couple.**

I read recently that letting water run while brushing teeth wastes 3-5 gallons of water.* Not being one to just believe claims of that sort, I decided to verify it by plugging the water in the sink while I brushed my teeth, which takes exactly two minutes with a Sonicare...measured the amount in the sink, and it was 3.2 gallons.*

To put this into perspective...If you brush twice a day, letting the water run, you can save enough water for two days of toilet flushing by wetting the toothbrush, then turning the water off till you're ready to spit and rinse.

Jay...you said, I bought one new raritan Sea Era head and converted the other Jabsco using the same devices that came with the Raritan.

*WHAT devices????

*


-- Edited by HeadMistress on Friday 15th of April 2011 02:26:53 PM

 

[markpierce]

HeadMistress wrote:
I read recently that letting water run while brushing teeth wastes 3-5 gallons of water.* Not being one to just believe claims of that sort, I decided to verify it by plugging the water in the sink while I brushed my teeth, which takes exactly two minutes with a Sonicare...measured the amount in the sink, and it was 3.2 gallons.

*I recently had a tiny,*undetected toilet leak at home which more than*tripled my water consumption (from 60 to over 200 gallons a day).

*


-- Edited by markpierce on Friday 15th of April 2011 02:35:21 PM

 

[rwidman]

HeadMistress wrote:
However, you cannot just decide to connect a sea water toilet to the onboard fresh water supply. That cannot be done without risk of e-coli contamination of the fresh water, damage to the toilet, or both and EVERY toilet mfr specifically warns against it in their installation instructions.* ONLY toilets that are designed by the mfr to use pressurized flush water should ever be connected to the fresh water supply.*

Agreed! (Says the guy who learned much of what he knows about boat plumbing from reading your book.)

This is very important and a simple check valve is not the solution some folks think it is.* What you're doing is taking a chance of drinking pooh!

It's called "cross contamination".

Now if you want to keep a bucket next to the sink and fill it with fresh water and dump it into the head to flush it, that's OK.* A pain, but OK.

To answer the original question, seawater may contribute to the odor problem, but you're not likely to run out of seawater.* I installed a filter between the seacock and the head intake to trap marine life that would otherwise be drawn into the head and decompose.* This has cut down on the odor problem considerably.

*

*



-- Edited by rwidman on Friday 15th of April 2011 04:02:47 PM


-- Edited by rwidman on Friday 15th of April 2011 04:03:58 PM

 

[HeadMistress]

Wow Peggie, you must have a very large bathroom sink to measure 3+ gallons.

Yup...When I renovated the bathrooms last year I put in Kohler sinks that hold* 3.6 gallons to the bottoms of the overflow holes. I LOVE 'em!

As for your "deferred" V/flush project. You might want to keep in mind that putting off a job often has a nasty habit of turning it into a much bigger more expensive project than it would have been if done sooner.

 

[JohnP]

markpierce wrote:
*I recently had a tiny,*undetected toilet leak at home which more than*tripled my water consumption (from 60 to over 200 gallons a day).

*

Mark,* I don't think an undetected leak would be undetected for long in the typical FW electric head.* The bowl would probably fill and overflow with the incoming water and the problem would become obvious very quickly.

JohnP

*

*

 

[jleonard]

"Jay...you said, I bought one new raritan Sea Era head and converted the other Jabsco using the same devices that came with the Raritan.

*WHAT devices???? "

I bought a solenoid valve and*a siphon break. (I think that's what it's called). Installed everything according to the Raritan instructions

I also removed the impeller from the pump cavity of the Jabsco and plugged the ports. It flushes as quietly as the Raritan now.

*

*

 

[Keith]

On my Krogen 42, I have raw water flush and wouldn't have it any other way. FW is fine, as long as you aren't going to do any extended cruising, have a water maker, or have tons of FW storage. No problems with raw water flush with mine. I'm a liveaboard, so use it all the time. Odor can be a problem if you're not flushing all the time, but there are ways around that. If I leave the boat for a few days, I just do the last flush with FW from the shower head and put a little KO or CP in the toilet.

 

[Codger2]

Keith wrote:
On my Krogen 42, I have raw water flush and wouldn't have it any other way. FW is fine, as long as you aren't going to do any extended cruising, have a water maker, or have tons of FW storage.

******** Same here, Keith.

*

 

[markpierce]

On an extended off-shore cruise, I'd opt for a bucket and avoid using a toilet dependent upon fresh water.

 

[Carey]

Here is what works for me. We have an electric Jabsco, which is set up to use sea water. However, after other efforts to eliminate odor from the system, I started keeping a gallon of fresh water next to the toilet, which we use for dealing with peeing. A quick shot of the flush button to evacuate the pee, then rinse the bowl with a cup or two of fresh water, then hit the button again to totally evacuate the toilet. This eliminates the introduction of a lot of biological stinking matter from entering the system via salt water. When dealing with solids, we add a cup or two of fresh water, and begin the flush. Being a longer flush, the pump does pick up some salt water to aid in the flush. I then do a final rinse of the bowl with a cup of fresh water. It sounds like a lot of messing about, but it is really quite simple, and uses very little fresh water. With two of us on board, we may use a few gallons of fresh water in a week, and it never smells.*


-- Edited by Carey on Saturday 23rd of April 2011 09:49:08 PM

 

[Tidahapah]

I have a FW maker (120 lt/hr) but still have my toilets connected to the SW. Have done for 16 years.
Don't have a problem with it. Have a new Raritan electro scan unit connected so will see how it operates once I get back into full time use.
Don't ever want to change over to FW flush if I can help it.
Benn

 

[HeadMistress]

It'll take only half as long to flush and rinse out the bowl if you add a cupful or two of water from the sink ahead of solids instead of only adding it to the flush.

You'll prevent sea water mineral buildup in the head discharge line if you flush a cupful--two at most...any more would be wasted--of undiluted distilled white vinegar through the system...ALL the way through the system. Do not leave vinegal sitting in the bowl, make sure you flush it completely out of the pump.

 

[Steppen]

Peggie,

How often do you recommend flushing the system (a system that uses sea water) with one or two cupfuls of distilled white vinegar?* Daily?* Weekly?

Thanks

 

[HeadMistress]

Not sure how I managed to leave that out...weekly. Doesn't need to be any more often...less frequently doesn't do much good. And before anyone asks, vinegar will not harm a LectraSan/ElectroScan. In fact, can actually extend the time between cleaning. It needs to be distilled white vinegar, not cider or any other type. Reason: distilled white vinegar is distilled from alcohol...cider, wine, etc vinegars are fermented fruit juice that can leave a sticky residue. White vinegar is also more acidic that any other kind, making a lot more effective.

 

[marinetrader]

But if you are doing some serious cruising away from fresh water sources and you have no water maker, I will stick to sea water

 

[HeadMistress]

markpierce wrote:
On an extended off-shore cruise, I'd opt for a bucket and avoid using a toilet dependent upon fresh water.

*Why not spec out a toilet for your new boat that can use both? Flush with sea water offshore (where the water is a lot cleaner and less "organic" anyway)...switch to fresh water in coastal waters.*

I know the "Sea Fresh System" can be added to the Raritan Elegance* Raritan Elegance toilet ...and I THINK it can be added to any toilet that's designed to use pressurized flush water.* It just can't be added to a sea water toilet.

*

*

 

[Codger2]

HeadMistress wrote:
*Why not spec out a toilet for your new boat that can use both?**

******* Good info....didn't know such a system was available.

*

 

[FF]

In homes there is a good reason that waste systems require a vacume breaker in any feed that goes to waste water.

A solenoid might work , but I have no idea on different failure modes , and pumping only a bit of black water into your FW tank could be a big medical bill.

 

[JohnP]

One way of using any existing head with fresh water flushing.* Is to install an inexpensive poly water tank dedicated to the head only.

Impossible to cross contaminate and also no loss of water capacity due to head use.

It would require a little effort to install properly, but even if you eventually bought a new head it would still be usable.

JohnP

 

[HeadMistress]

You'd need more than just a vacuum breaker to prevent bacteria from migrating into the fresh water plumbing. It's also important to remember that sea water toilets are designed to PULL water into the pump....pressurized fresh water PUSHES water through the pump. There is no intake pump...a solenoid valve (not the same type as the solenoid valve in a vacuum breaker) in the intake opens and closes to ALLOW water to flow into the toilet...like opening a faucet and closing it.

A separate flush water tank isn't that simple actually...it must be totally separate from the potable water system...separate fill, separate vent...so there can be no cross-contamination.

By the time you do all the surgery required to turn a sea water toilet into one that can use freshwater, you'd spend almost as much as a new toilet.

99% of sea water odor problems are caused by sea water left to sit and stagnate in the head intake while boat sits...and just pouring fresh water into the bowl can't solve that problem because what's in the bowl only goes through the discharge pump and down the discharge line, it isn't recirculated (thank God!) through the intake. There's a very simple--and very inexpensive--solution that problem: a y-valve in the head sink drain line with a line off it that also tees into the head intake line. To rinse the sea water out of the WHOLE system, simply turn the y-valve to open the sink drain to the head intake line....fill the sink with clean water...flush. The toilet will pull the water out of the sink. If your sinks drain below the waterline (as they do on most sailboats, but not on most powerboats), you don't even need a y-valve...just tee the head intake line into the head sink drain line below the waterline. The toilet and the sink will work just fine, although you'd have to keep a plug in the sink to flush the toilet with sea water . Just close the seacock to fill the sink to flush with fresh water.

 

[Ed]

HeadMistress wrote:
Not sure how I managed to leave that out...weekly. Doesn't need to be any more often...less frequently doesn't do much good. And before anyone asks, vinegar will not harm a LectraSan/ElectroScan. In fact, can actually extend the time between cleaning.

*Peggy,

I haven't read my LectraSan manual for a while but I don't remember any cleaning instructions in there.* Are you talking about removing the electrode, cleaning and replacing it?

*

 

[MYMT]

Hi, new guy here. Just bought a MT Trawler and am learning the ropes so to speak. I have been reading all the comments about fresh water flushing and thought I'd ask...I have a gray water tank for the shower that has a sump pump and am thinking of utilizing the gray water for a fresh water toilet flush. Will reroute the drain hose from the sink and maybe raise the float level in the tank just a bit to ensure an adaquate amount of water for flushing. The gray water doesnt stink now, and I supposed it would be fairly easy to keep some kind of order/cleaning solution in the tank if it became necessary. Seems like a good idea to me, but I may be overlooking something...what do you think?

 

[Marin]

Unfortuantely the person who can best answer your question, Peggy Hall, has retired from internet forum participation. However she said that she will still answer e-mails, so if you can find her address--- try the T&T list archives unless someone here happens to have it--- I'm sure she will give you the benefit of her long experience with all aspects of marine sanitation.

I'm not sure your idea is a good one but I don't have the knowledge or experience to definitively say why. So try to get hold of Peggy.

 

[MYMT]

Thanks Marin, I'll see about getting her email...

 

[BobH]

The problem with sea water flush is that if you don't use the toilet for a while the water in the flush lines starts to stink. All kinds of organism in there die off. It's not a problem if the toilet is in daily use.

On our previous boat we used sea water while cruising, but if the boat spent any time in a marina not being used we changed to fresh water flush.

Bob