Solenoid For Plumbing?

[scarlet]

So my project for the spring will be replacing all my hoses for my heads. As long as I'm doing this, I would like to change over from raw/sea water flush, to fresh water drawing from my water tanks. I talked to a plumber and he said the most expensive part of the project would be adding a solenoid valve. Why would I need that? I would think a "y" valve to chose between raw/sea water and the fresh water would be all you would need. But he insisted that I needed one. After his review of what I would need, I decided that I would do the plumbing myself, but I'm still wondering WHY I would need a solenoid (btw... I have electric heads).

The other thing I wanted to ask, he said that the hoses from the toilet to the holding tanks was 1" hose... but it looks bigger than that. I would guess 1 1/2".... is he right?

[peghall]

Sea water toilets aren't designed to use fresh water. They have intake pumps that PULL flush water in, all toilets designed to use fresh water don't have intake pumps because they're designed to use pressurized water...which is why you'd need a solenoid valve. It acts much the same way a faucet does...open to allow the water into the bowl, close to shut it off. However--you'd also need to install a siphon break and backflow preventer--which are built into toilets designed to use fresh water--to protect your potable water supply from contamination from the bowl. But that still wouldn't let you switch at will between fresh and sea water...that would put your fresh water supply at risk of sea water contamination.

There are toilets designed to use both, but only the expensive all china "thrones" and they have two inlet connections on the bowl--one fresh water, one for sea water, a remote intake pump for sea water and that pesky solenoid valve for the pressurized fresh water.

So if you want to flush with fresh water, your best option is: replace your toilet with one designed to use pressurized fresh water. A "conversion" (everything south of the bowl) lets you keep your existing bowl seat and lid and are reasonably priced.

As for your hose: You're prob'ly making the same mistake a lot of people make: measuring the OUTSIDE diameter of the hose. Hose sizes always use the INSIDE diameter because wall thickness can vary a lot, depending on whether the hose is single walled or double walled rubber. Hose FITTINGS always use the OUTSIDE diameter because the hose has to fit ONTO it. If your plumber thinks you have 1" hose, I'm guessing that means your toilet is a Jabsco, most likely 37010.

If you're replacing hoses, that's the last thing you want to "go cheap" for if you only want to do this job once. I strongly recommend you go with Raritan SaniFlex RaritanSaniFlex hose Not only has it proven to be the most odor permeation resistant, but it's also so flexible it can be bent like a hairpin without kinking. Defender has it on sale for about $8/ft right now Raritan Sani / Flex Sanitation Hose at Defender


Give me a shout if you need more help deciding what to do and how best to do it.


--Peggie

[scarlet]

I was going to use Shield's Poly-x... I thought they were the top of the line...

[jamhass]

Or, as Peggie has often suggested, replumb the head inlet to the sink drain line. Closing the drain seacock and filling the sink with fresh water lets the head draw fresh water without risking contamination.

[peghall]

Originally Posted by scarlet

I was going to use Shield's Poly-x... I thought they were the top of the line...

They're actually just the most expensive of the 3 "top of the line" sanitation hoses...
Trident 101/102 (identical except 102 has a white "skin" on it) has been on the market for about 25 years without a single reported odor permeation failure...average price $7-8/ft. But it has one major drawback: it's as stiff as an ironing board, making it a less-than-ideal choice in systems that have a lot of turns.

Shields PolyX has a lifetime warranty against odor permeation, but since 10 years is the average working life of ANY hose, that's good PR but that's all. I base my recommendations on track records and I haven't seen or heard from enough people who've paid the price for it (cheapest I could find was $16.50/ft) to know whether it actually lives up to its hype.

But I do know that Raritan SaniFlex has been on the market about 10 years now without a single reported odor permeation--and more importantly, I haven't heard of a single one either and I'm pretty sure I would have by now 'cuz a lot of people are buying it. And while it has a list price of $14/ft, it's not hard to find for $8-10/ft.

That's my $.02 worth anyway...

--Peggie

[peghall]

Great idea, but the head sink drain has to be below waterline and on the same side of the keel as the toilet.


If you've done it, jamjass, 'how bout posting detailed instructions?


--Peggie

[s/v Jedi]

Here’s your best option: use the hand shower to get fresh water into the bowl, use the pump-dry mode of the toilet to pump it out

[peghall]

She has electric toilets, which don't have a dry mode. Closing the seacock and using the shower head would result in a fried intake impeller. But that's not the best option using a manual toilet either.



--Peggie

[jamhass]

Originally Posted by peghall;

Great idea, but the head sink drain has to be below waterline and on the same side of the keel as the toilet.


If you've done it, jamjass, 'how bout posting detailed instructions?


--Peggie

In our boat, the sink and head raw water inlet are in the same under-sink space. I simply put a T in the sink drain link and plumbed it (with a ball valve) into a T in the raw water line to the head.

To use, close the sink drain seacock, close the head raw water seacock, open the ball valve, fill the sink and use the head as normal. After a few flushes you will see how much fresh water you need to add to the sink for a flush.

The ball valve is there to keep the head (and in our case, the deck wash) from sucking air when using sea water.

Sorry, thought I had a photo, but no joy.

[s/v Jedi]

Originally Posted by peghall

She has electric toilets, which don't have a dry mode. Closing the seacock and using the shower head would result in a fried intake impeller. But that's not the best option using a manual toilet either.

--Peggie

My electric toilets did have a dry mode. Without dry mode, I would just replace the toilets with proper fresh water flush toilets, which I did anyway.

[scarlet]

Originally Posted by s/v Jedi

My electric toilets did have a dry mode. Without dry mode, I would just replace the toilets with proper fresh water flush toilets, which I did anyway.

How much do freshwater toilets cost?

[velero]

You should use a latching solenoid (known by other names). Its similar to your car auto power windows, it latches up/down position without using power. I experimented with cheap Chinese solenoids for 1/2 in tubing. I have three tanks that I want to turn on/off without opening the floor boards. they are on all the time and get hot - not good. Latching will not use any power but they are expensive. A 1/2 in cheap non latching is about 5 bucks and a latching is around $100.

[ggray]

Originally Posted by peghall

Great idea, but the head sink drain has to be below waterline and on the same side of the keel as the toilet.


If you've done it, jamjass, 'how bout posting detailed instructions?


--Peggie

I tried to quote both Peggie and jamjass, but didn't work.

I plumbed our heads this way as suggested by Peggie I thought, but I would describe it as plumbing the sink drain to the head intake hose, not the other way around. This would address Peggie's concern above.

Many advantages. Easy to change flush water from raw to fresh when desired. Easy to winterize head with antifreeze. Easy to lubricate head pump with vegetable oil (I know, I know, I don't do it anymore). You can use the head when hauled out. For OP, when he gets low on fresh water, just use sea water. One more--- after 19 years and probably 9 bottom paintings, I didn't notice that the last paint job sealed up the perforated strainer on the head intakes. We just filled the sink (if it wasn't already) and the head worked fine, until I could open the holes.

[CaptTom]

One question, and one somewhat-related comment:

Originally Posted by ggray

I plumbed our heads this way as suggested by Peggie I thought, but I would describe it as plumbing the sink drain to the head intake hose, not the other way around.

This is an interesting idea, and I'm trying to picture how this would be used, day-to-day.

So, do you close the thru-hull for the sink drain, and leave water in the sink (or at least, the drain) until it gets used in the head? Basically, you've made what amounts to a grey water tank out of your sink, to supply the flush water?

I really like the idea, and a simple turn of the thru-hull valve switches between raw water flush and "grey water" flush.

Comment on Solenoid Valves:

I plumbed this one into the water heater line carrying engine jacket water. It opens when I turn the "ignition" switch to start my starboard engine, and closes when I turn the switch off.

This reduces heat loss to the block from the water heater. My hot water lasts longer at anchor, and it even saves me money at my home dock (where electricity is metered.)

It's worked well for the past four years. Well worth the $15 I paid for it, and the installation was pretty simple.

[peghall]

This is an interesting idea, and I'm trying to picture how this would be used, day-to-day.

So, do you close the thru-hull for the sink drain, and leave water in the sink (or at least, the drain) until it gets used in the head? Basically, you've made what amounts to a grey water tank out of your sink, to supply the flush water?

I really like the idea, and a simple turn of the thru-hull valve switches between raw water flush and "grey water" flush.

This is how it should be installed and how it works:


Reroute the head intake line to tee into the head sink drain line BELOW the waterline, as close to the seacock as possible. Requires only a simple tee. This allows you to flush the toilet normally using sea water (obviously the drain thru-hull remains open). To rinse the sea water out of the whole system--intake line, pump, channel in the rim of the bow AND the toilet discharge line (anything just added to the bowl only goes out through the discharge line, it doesn't recirculate through the rest of the system--and you wouldn't want it to!),



To rinse the sea water out of the whole system before the boat will sit, close the thru-hull, fill the sink with CLEAN water (never use gray water!), flush the toilet. Because the thru-hull is closed, the toilet will pull the water out of the sink. Or you can opt to flush with fresh water all the time if you want to...just requires keeping the sink drain closed except when using the sink.



This also makes winterizing very easy...just pour the antifreeze into the sink--with the thru-hull closed, of course--flush the toilet.


Why should you never use gray water? Because it's full of bacteria, soap scum, body oils, dirt and grime that can foul up a toilet pump and also create odors instead of preventing 'em. So send your gray water overboard and only use CLEAN water to flush the toilet.



I didn't invent this...years ago several boat builders plumbed toilets to use the same thru-hull as the sink drain as a way to eliminate one hole in the boat and also save 'em the cost of a thru-hull and seacock. A customer owned a Tartan plumbed that way, told me about it, and I fell in love with the idea. It does require that sink drain thru-hull be below waterline and that the toilet and sink be on the same side of the keel.



--Peggie