Grey Water Sumps, Pumps and Johnson Ultima Float Switches

[LtBrett]

I have a water witch and I would have some concerns about using it in a greywater system. The johnson switch uses the same sensing technology, and it may have similar weaknesses. Specifically, when there are contaminants around, the switch either will not turn on or will not turn off (that scares me). If oil gets on the contacts, it won't turn on. If antifreeze gets on the contacts, it won't turn off. I solve the problem by keeping a pretty clean bilge and periodically wiping the contacts. But I concluded that these types of float switches are not as impervious to liquids as the manufacturer leads you to believe. The Johnson unit may work, but I would dig a little deeper. What is the state of the art in black water switches?

Brett

[Pelagic]

I have the same solution as Nick, except our grey water tank came equipped with a tank tender (Green/Yellow/Red light) and manual switch installed midships beside the dining salon.

When it goes from Red to Yellow about every 2nd day we pump out (usually harmonized with generator time). This gives me a reminder of water consumption and avoids pump out when we are swimming.

[Christian Van H]

This is what I was referring to: Marine : Whale Pumps 12V Henderson Plumbing Bilge Diaphragm Submersible Pressure Water Systems Marine Caravan RV Shower Drain Portable Sanitation Purging Groundwater Solutions Voltage Electric

It's first on my short list for sumps...

[Pelagic]

Originally Posted by Pelagic

I have the same solution as Nick, except our grey water tank came equipped with a tank tender (Green/Yellow/Red light) and manual switch installed midships beside the dining salon.

When it goes from Red to Yellow about every 2nd day we pump out (usually harmonized with generator time). This gives me a reminder of water consumption and avoids pump out when we are swimming.

Sorry I meant Green to Yellow......Red is Full

[akio.kanemoto]

Originally Posted by s/v Jedi

We have a gray water tank and had so much trouble with everything about it. It took us years to come up with a solution that only needs simple maintenance once every 6 months (and believe me, that is very good!).

We have one central gray water tank, which is in the keel-sump. All gray water drains in there by gravity, like in a house, and that part is fantastic. This also means you only have one pump, one set of wiring, one floatswitch, one breaker/fuse etc. I would advise to do this if possible. Build a tank in the bilge with some plywood, glass and epoxy. We have a perspex lid with rubber gasket. We mounted a standard Beckson inspection lid in the perspex lid for quick access during maintenance. Choose the size so that your fist will pass it.

Now is where the trouble starts: pump, float-switch, discharge and pickup hoses, strainers etc. Macerating pumps are worthless as they quickly seize with hair around the shaft/knife/impeller. A big step forward was the Whale Gulper 220 pump. Get it and you solve half the headache. This pump will pass anything that can pass it's inlet.

But the float-switch is bad too. The previous owner started with a Waterwitch electronic switch which failed to trigger often as fatty residue covered it (that is soap residue!). He changed to one of those very expensive switches with a float inside a tube and that was what we got with the boat. I hated that so much because the float would quickly seize inside the tube and all the holes would clog etc. When the switch fails, you are in trouble because the tank will overflow. Not just through the drain in the heads but also through the lid because the gasket is never perfect after some period of use. We decided that this will not do and started experiments. I will skip all the failures and come straight to our solution:

Pick-up pipe: Buy a 3/4" PVC adapter from pipe to thread. Cut a hole in the lid that just fits this adapter and use sanding and JB weld to fit it into the lid, with threads facing up. Now put the lid on the tank and measure the distance to the bottom of the tank through the adapter (to the top of the adapter). Cut a piece of 3/4" PVC pipe (schedule 40) to that size and fit it to the adapter with PVC cement. It will be too long. Keep cutting off small pieces until it is about 1 cm (1/2") above the bottom of the tank. That's it, no strainers, just $1.- worth of PVC. Now mount a 90 degree PVC elbow thread to hose-barbs on the adapter using Permatex no. 1 as thread sealant. This part is never going to wear out and will never clog.

Float switch. Use the cheapest Rule switch you can get: the type with that hinged plastic float. Buy 3 of these (add 2 to your spares). The trick is to mount this switch at the bottom of the pick-up pipe. We made a mini-bracket out of King Starboard and attached that to the pipe with hoseclamps. We actually used monel wire with our spiff Clamptight tool but hoseclamps will do. You probably have to cut some slits in the bracket to pass the hoseclamp through, this is why you need a Dremel or (and) Rotozip tool aboard.
Drill a little hole for the wire through the lid, pull the wire through and fasten it to the pipe with plastic wire ties. Mount a small terminal-block on top of the lid, put the expensive heat-shrinked terminals on the two wires and connect them to the terminals. Put a little dot of silicone where the wire comes through the lid (both sides). Done.

Discharge pipe: we already had a 1.5" hose coming to the tank so we fit a 1.5" PVC coupler (female thread to female thread) in the lid just like for the pickup tube. We mounted a 90 degree PVC elbow (thread to barbs) on top to accept the incoming 1.5" hose. We mounted a straight 1.5" thread-to-barbs fitting on the underside of the lid plus a piece of hose. That piece of hose will not be straight, it will have a bend from being rolled up. Use that to your advantage and mount it so that anything entering the tank falls on top of the float-switch. I know that Nigel Calder writes to keep the float switch as far away from pick-up tube and discharge hose as possible. I also know I had a lot of failures before finding this solution... believe me, this is what works. The float-switch is auto-cleaned and everything will work great.
There's one more thing to this: if you ever need to take the lid off, you have that 1.5" hose attached to it's top making your life miserable. You can't put the lid aside. We solved this with a very smart coupling from Good Turns. It has right-hand-side thread on one end and left-hand-thread on the other. You turn it one way and it couples the hose, the other way and they come apart without using knifes, heat-guns, dremel etc. We had to hunt on-line stores to find one but it's worth it.

80% of trouble solved, 19% to go: you need to find a solenoid equipped with a timer. We used one off an old Raritan electric head (it times how long it flushes after pressing the flush-switch). I see it in the catalogs so it's there. Mount that solenoid between float-switch and pump so that the pump will continue pumping after the float-switch switches off again. This timer can be set using a mini screwdriver. This trick only works with the Whale Gulper pump because it can pump water-air mixture or even just air (like manual bilgepump, it's the same thing). Start filling the tank until float switch activates. As the pump evacuates the water, it will start drawing air but still pump liquid too. At this point, it will pump nasty stuff that floats in the tank. Adjust the timer so that the pump stops when it is only pumping air (clear hoses help a lot here). The gulping sounds go neatly with the Gulper pump and they also let you know all is okay in there.

1% trouble left.... can't get rid of it but this is what we do for maintenance: once every 6 months we open the Beckson-lid, shine a light in and yell Bah! Hose it down, close the lid and done. 5 minutes.

After two years the float-switch failed. Replaced in 30 minutes incl. changing mounting holes because Rule decided to upgrade and change the switch. That's why you need to buy 3 the exact same ones ;-)

We have this setup for over 4 years now and no more trouble. I think the upgraded float-switch is better because it still works but that might also be because I now have the exact same ones as spares lined up.

cheers,
Nick.

Thank you for the very detailed reply - sounds like a great solution indeed.

For the box - I was planning on using just ply, putting fillets in each corner to add strength and make it round to reduce build up and then coating inside/outside with epoxy - you mention glass as well - any particular reason? The sump should be strong enough by itself?

I also love the LHS/RHS thread idea, but being in Australia, we have very poor access to anything "out of the ordinary" without going to a specialist supplier and placing a special order - and everything is ludicrously expensive. So I can manage the lot, except this part I imagine.

On your discharge line from your Gulper - do you have it go up to an anti-siphon loop? My sump is about 50cm below the waterline, and I have a choice of mounting the pump up to even 1.5m above the waterline or anywhere in between but can only discharge up to about 50cm above the waterline (transom under counter) - but there is not a straight downhill run. The other option is to discharge amidships near the WL...

Actually, I haven't decided on discharge locations for the bilge pumps either, so I guess the exact question can be applied to both scenarios. (As additional info I have two sets of bilge pumps - "daily" and "emergency" - daily is in the bilge, remote mounted Gulper again, and emergency is about 20cm above, 2 x rule 2000's).

[akio.kanemoto]

Originally Posted by Christian Van H

This is what I was referring to: Marine : Whale Pumps 12V Henderson Plumbing Bilge Diaphragm Submersible Pressure Water Systems Marine Caravan RV Shower Drain Portable Sanitation Purging Groundwater Solutions Voltage Electric

It's first on my short list for sumps...

I wonder what switch they use?

[akio.kanemoto]

Originally Posted by LtBrett

I have a water witch and I would have some concerns about using it in a greywater system. The johnson switch uses the same sensing technology, and it may have similar weaknesses. Specifically, when there are contaminants around, the switch either will not turn on or will not turn off (that scares me). If oil gets on the contacts, it won't turn on. If antifreeze gets on the contacts, it won't turn off. I solve the problem by keeping a pretty clean bilge and periodically wiping the contacts. But I concluded that these types of float switches are not as impervious to liquids as the manufacturer leads you to believe. The Johnson unit may work, but I would dig a little deeper. What is the state of the art in black water switches?

Brett

Actually googling a little bit further, while there are positive reports on the Water Witch, I haven't really found much in the way of positive reports about the Ultima.. sounds like a dud indeed. :\

[s/v Jedi]

We tried something similar too (filling up the tank before emptying it) but decided it's better to get rid of that muck a.s.a.p. That actually helped as the muck gets less time to stick to the tank/float etc. The shorter you have it in the tank, the cleaner it stays.

We also have manual override switches at every sink and used those a lot when the float-switch was seized in muck with the old system. I completely forgot about them until reading Pelagic's message ;-)

cheers,
Nick.

[Christian Van H]

Originally Posted by akio.kanemoto

Actually googling a little bit further, while there are positive reports on the Water Witch, I haven't really found much in the way of positive reports about the Ultima.. sounds like a dud indeed. :\

You have found positive reports of electronic sensor type switches being used successfully in grey water sumps?

[s/v Jedi]

Originally Posted by akio.kanemoto

On your discharge line from your Gulper - do you have it go up to an anti-siphon loop? My sump is about 50cm below the waterline, and I have a choice of mounting the pump up to even 1.5m above the waterline or anywhere in between but can only discharge up to about 50cm above the waterline (transom under counter) - but there is not a straight downhill run. The other option is to discharge amidships near the WL...

We are blessed with standpipes for discharge aboard Jedi. The standpipe we use for this pump is vented by some drains from the pilothouse above it. I don't think you need a vent as long as the thru-hull is above waterline.

cheers,
Nick.

[akio.kanemoto]

Originally Posted by Christian Van H

You have found positive reports of electronic sensor type switches being used successfully in grey water sumps?

No, only for bilge applications. :\

[akio.kanemoto]

Originally Posted by s/v Jedi

Aha! No need to worry, you can buy drains that do the job. They are made by ForeSpar and sold by Lewis Marine in Ft. Lauderdale (there will be others but not WM... maybe they can order them). They are even in their catalog somewhere, if you manage to decode their indexing system. They are for super-shallow installation height, you can't see from the outside that they have a trap but they do. When we empty the galley sink after doing the dishes, they make a nasty sound and even spit some water out because our gray water tank has no vent ;-)

cheers,
Nick.

[IMG]file:///C:/DOCUME%7E1/Umar/LOCALS%7E1/Temp/moz-screenshot-7.jpg[/IMG]
Do you mean the right angle SW-2 fitting on page 16? (right angle drain)

http://www.forespar.com/onlineCatalo...lonCatalog.pdf

Or you mean there's one with an actual mini-trap as well? That would really be impressive!

[s/v Jedi]

The Forespar SW-4 is what we have. I'm doubting that waterlock feature now because I don't see it in the description and realize it might happen on the connecting manifold (2 drains into one hose for draining on both tacks). The manifold is just a T and hose and might come up a bit before going down to the tank. You could do that to as these fittings save a lot of room.

Now we have that catalog open: on page 4 is a Marelon valve. This is what many people use for seacock but it isn't, it's just a valve. The problem with handle breaking is this valve. The cause is that it has two parts that can be un-screwed for access to the ball seals for maintenance. If these two parts are to tight, you can hardly move the handle anymore, so they are overtightened in that case. Many people (incl. me until I found out by accident) don't realize it has the two parts and they get overtightened when fittings are screwed into the valve.
On page 6 are the real sea-cocks. They have the mounting-flange and are 1 part only. I never had a problem turning these and love them!

On Page 17 is the Lanocote which is perfect for turnbuckle threads and valves.

cheers,
Nick.

[boden36]

We have a sump for the shower with a Rule electric pump. You need grates like the one that goes in the kitchen sink to catch the hair and bits at source, rather than in the tank. The tank must be accessible for a periodic clean and the pump easily removable for the same reason.
Use Rule hinged floats as in an earlier post. If you use two floats ( one for lower level, and one for upper level) and a relay to create a "latching circuit" the pump will turn on when the tank is full and then pump the tank empty. This stops the pump stopping and starting all the time.
Regards, Richard.

[Christian Van H]

Just an update guys...I bought the Whale sump tank at Defenders open house, and also spoke to the Whale Rep there. Turns out that Whale changed the sensor in the tank recently. Instead of a float switch, it now uses a solid state sensor without the need for a relay. This new sensor DOES NOT have bare metal contact points and, according to Whale, will not foul. One other cool feature; the sensor is mounted to the screw out inspection plate. Unscrew the plate and the sensor comes right out with it. Well worth the $130 I paid, I believe!