Fresh and sea water to electric toilet

[BillBerner]

Hi all -
Need somebody to say why this may be a terrible idea.
Our boat, before we owned it had the jabsco electric plumbed to the fresh water line. Great on short weekend trips. Never any smell.
But not so great when we’re out for extended periods and need to be more careful about fresh water usage.
I’ve also
Been want I got to put in a raw water wash down system in the anchor locker.
So I’m thinking on can kill 2 birds with 1 stone.
I want to put in a wash down pump with a y (or if necessary tee) on the output side. One side of the y goes to the wash down hose and nozzle. The other goes to one input side of a diverter. The other input gets connected to the fresh water line.
Now I can select whether I want to flush with fresh or raw water, and always have a wash down available.
Does this make sense, or what am I missing. Potentially polluting my fresh water with back flow of the raw. Maybe a quick shot of fresh after using raw eliminates that worry?
Thanks

Bb

Thanks

[R.B.]

Hi Bill,

Not sure how they plumbed the fresh water to your head, but that would seem to be where the risk for contaminating your fresh water tank is. I have heard of people that wanted fresh water for flushing, plumbing in a t-connector to your sink drain, and using the hand washed water for flushing your head. We just use the shower hose to add water to our head when needed.

Your idea of using the sea water for both the head and wash down pump sounds good, but again, any connection to your potable water system to non-potable water sounds risky.

Just my $.02

Good luck!

-Ralph

[BillBerner]

I think I’ve got the back flow problem solved
It requires a little more hardware (of course)

The plan is to run the raw water feeding the toilet thru its own vented vented loop. The fresh water flushing system has a vented loop that also has a solenoid connected to the Jabsco switches, that opens a valve allowing the fresh water to flow to the toilet.
I’ll connect the output sides of both center loops to the input sides of the diverter. Hence no chance of polluting the potable water system with raw.

Electrically I’ll need to put a switch in line on the wash down pump. The load side of the switch will also be connected to the load side of the flush, and bowl fill of the jabsco switch. I may have to up the
Amperage of the breaker and wiring feeding the jabsco switch. & the switch itself will have to be able to
Carry the load of the additional pump.

When flushing with fresh water the switch for the wash down pump can be left on, so the wash down system can be used any time. When the diverter is switched over to raw water, I turn off the switch to the wash down pump so it is only powered up when toilet switch is engaged.
Whaddya think, folks. If I want to use the wash down on days we’re flushing with raw, I’ll have set the diverter temporarily back to fresh, and turn the switch back on.

Not perfect, but in general, I like it. That is until one of you points out the flaw I. The plan.

[Strgzr]

We just use the shower to rinse with FW. It has a length of hose and removable hand held shower head. I don't want the head any near the FW system otherwise.

[jreinhold]

I've used the shower to do a quick rinse of the bowl on the 350 we bought in the fall. But I recently opened the through hull for the head intake and heard quick a sucking sound, indicating the pump was pulling suction on the through hull. This concerns me both from the constant pressure on the through hull and the work the pump is doing to pull the vacuum. Has anyone else noticed this and is anyone else concerned about it?

Jim Reinhold
Tranquility #332
Perth Amboy, NJ