Solenoid Seacocks for Electric Toilets

[Dockhead]

I really hate the way the seawater intakes for my electric toilets are plumbed.

Below the waterline, I have: single-clamped flimsy plastic seawater strainer, connections to the seawater pump, the workings of the seawater pump. Only after that, is there a vented loop. This is -- Just Wrong! Even a crack in the seawater strainer will mean seawater leaking into the boat.

One approach already suggested to me would be to put the vented loop ahead of the pump -- but with a solenoid vent, so that the pump can draw suction when it's running.

It occurred to me that if we can do a solenoid vent, why not do it one better and have a solenoid seacock, to just keep the seawater intake altogether shut off unless the pump is running? Why not? Wouldn't that be simpler and much safer?


The other alternative is to eliminate the problem altogether by plumbing them for fresh water. I don't really like this because my boat is on a mooring without ready access to fresh water, so I am often conserving it. Besides that, I believe in thoroughly flushing through boat waste systems, and you would have an internal conflict doing this with limited fresh water, as opposed to unlimited and free seawater.

So how about the solenoid sea cocks? Does such a beast exist? It's so logical for this, and possibly other uses as well.

[Dockhead]

Danfoss makes a Normally Closed solenoid valve with 1/2" G connections and a 24v coil -- neat. It's available in Dezincification Resistant Brass and is ok for seawater according to Danfoss: http://www.ra.danfoss.com/TechnicalI....200.D6.02.pdf

Maybe that's the ticket? Just connect it directly to the ball valve, and wire it in parallel with the toilet flush switch?

[Palarran]

Why would the strainer crack? It seems like a lot of work and adds to weight and complexity for little reason. Can't you put another hose clamp on?

[Dockhead]

Originally Posted by Palarran

Why would the strainer crack? It seems like a lot of work and adds to weight and complexity for little reason. Can't you put another hose clamp on?

It's a flimsy bit of plastic. Someone could step on it and not even notice it. For example.

And the hose barbs are too short for double clamps.

I suppose I could substitute a more robust strainer; a bronze one from Groco for example. But there are still plenty of failure points, including the pump itself and the patent clip in job where the hose goes into the pump, which I don't trust.

Yes, maybe I'm being anal about it and maybe it's not worth the complexity, but damn I hate that particular bit of plumbing. It would not actually be a huge amount of work to install -- the only question mark being whether the solenoid valve might not need some kind of support. The wiring is 10 minutes, and the plumbing should be simple.


Weight? Ha, you cat sailors and your weight . . . We're a 54 foot mono with a cored Kevlar hull and lightweight Yanmar main engine . . . bring on the cargo; we won't even notice it . . . Water tanks full or empty are one metric ton of difference, and you cannot detect the difference on the lines or in sailing qualities . . .

[Dockhead]

P.S. -- I'm not the only person who is uncomfortable with open sea cocks and funky toilet plumbing --

Dashew's Sundeers have all the seacocks behind watertight bulkheads fore and aft, so that no hose or sea cock failure can sink the boat. That's really good design as far as I'm concerned!

[Palarran]

I'm sure I know exactly which cheap strainer you have because I've got one for my refrigerator system. It's always loosing it's prime so I have to pull up the floorboards and burp it. There is an amazingly little amount of water that comes out even when the bowl is totally removed. So for me, the highly unlikely chance that someone will step on it is further minimized by the use of a bilge pump in case that did happen.

As far as weight, no doubt you don't have to worry about it, and I've got an especially heavy cat. But what I'm constantly trying to do is simplify installs if possible. Electro-mechanical equipment will fail at a higher rate then purely mechanical.

[HopCar]

I think you're going overboard, but if you want a remotely controlled seacock, Groco makes one. You would need their FBVE-750 for your 3/4" toilet intake.

My suggestion would be to just upgrade the hardware you are concerned about.

On the other hand it might be nice to have all remotely controlled seacocks on your boat. That way it's easy to shut them all if you are leaving the boat for a while.

[Dockhead]

Originally Posted by Palarran

Electro-mechanical equipment will fail at a higher rate then purely mechanical.

Wise words, of course.

I am still vacillating. I religiously shut off sea cocks when I'm not on board. They are very accessible and do not find this burdensome -- it's a deeply ingrained habit. I have a high capacity electric bilge pump on top of the regular maintenance pump.

Maybe I should take the cap off the strainer and see if the bilge pump easily keeps up. If it does, then maybe I'm overreacting to the risk.

Thanks for all the useful thoughts.

[Dockhead]

Originally Posted by HopCar

I think you're going overboard, but if you want a remotely controlled seacock, Groco makes one. You would need their FBVE-750 for your 3/4" toilet intake.

My suggestion would be to just upgrade the hardware you are concerned about.

On the other hand it might be nice to have all remotely controlled seacocks on your boat. That way it's easy to shut them all if you are leaving the boat for a while.

Thanks! What is the cost of those Groco seacocks? Can't seem to find anything in the 'net.

[azsailor12]

The problem I see with a solenoid seacock is that you can't visually check if it actually closed when you triggered it. At least a handle is obvious!

[Dockhead]

Originally Posted by azsailor12

The problem I see with a solenoid seacock is that you can't visually check if it actually closed when you triggered it. At least a handle is obvious!

I would not use a solenoid seacock instead of, but rather, in addition to the regular one!

Although the solenoid valves I saw (from Danfoss) are NC or Normally Closed, so will be closed by a spring unless energized.

[HopCar]

The Groco remote control seacock comes with a screen that indicates the status of the valve. It also has a handle that allows you to operate manually or check it visually.

It's not a solenoid. It appears to be a regular Groco seacock driven by a gear motor. I think Apollo also makes one but without the nice control screen.

It's brand new and I've never seen one. I'll look for it at the Miami Boat Show next week.

I can look up the price on Monday. Won't be cheap I'm sure but it looks like a well thought out system.

Groco's website drives me crazy because I can't copy and paste from it.
Go to their website: GROCO MARINE PRODUCTS
Click on 2014 Catalog on the left side of the page. The E-Valve is a few pages in.

[Dockhead]

Originally Posted by HopCar

The Groco remote control seacock comes with a screen that indicates the status of the valve. It also has a handle that allows you to operate manually or check it visually.

It's not a solenoid. It appears to be a regular Groco seacock driven by a gear motor. I think Apollo also makes one but without the nice control screen.

It's brand new and I've never seen one. I'll look for it at the Miami Boat Show next week.

I can look up the price on Monday. Won't be cheap I'm sure but it looks like a well thought out system.

Groco's website drives me crazy because I can't copy and paste from it.
Go to their website: GROCO MARINE PRODUCTS
Click on 2014 Catalog on the left side of the page. The E-Valve is a few pages in.

Thanks; much appreciated!