A Watermaker, What Fun!

Now… for you techies out there:  How about a water maker installation?

Dremel tool cutting the high pressure hose.  Nice sparks, huh?

I searched on the web.  I talked to experts and liars on the docks; hard to tell the difference.  I read books and magazines.  I considered the Cruise RO and the Spectra.  The Cruise Ro uses standard parts which are easily replaced and it uses the ubiquitous Honda 2000 generator as a power source.  The Spectra is the gold standard of 12 volt systems and there are folks in Mazatlan and La Paz who can service it.  But I’d done business with the folks who make the Hydrovane wind vane system and respect that design for being simple and sturdy.  You might say their systems are overbuilt.  But on a boat, tough and simple is a good thing.  So we went for the EchoTec, from the makers of the Hydrovane.   I ordered it with lots of emails back and forth with a guy named Will and had it delivered to Connie’s sister’s house in Phoenix.  We picked it up there a few weeks ago.  Price tag?  Let’s not go there.  Look it up yourself. 

At the border we got the green light… twice, so we did not have to show our paperwork proving that the unit was for a boat imported into Mexico.  When you go through customs in a car, you pull to a stop light and randomly get a red or green light.  If red, you pull over for inspection.  If green, you boogie on your way.  We boogied. 

Back at the boat in Mazatlan, we stashed all the water maker parts under the port side settee then did the crossing of the Sea of Cortez over to La Paz.  Once anchored there in the bay we started in on the installation.  This install is right up my alley.  It’s just a bunch of lightweight plumbing, some electrical, and a fair amount of mounting things to bulkheads and cabinetry.  I had about eight different gizmos that had to be connected together.  The great thing is that all this stuff does not have to be in one place.  You can spread it all out using the extra spaces under cabinets and floorboards.  

 

Reverse Osmosis Membrane in the port side settee

I started with the big stuff.  The largest item is the compressor and motor. This is a heavy dude and has to be firmly bolted down on its rubber mounts.  I found space under the port side settee.  Then there is the four foot long reverse osmosis membrane.  It fit in forward of the compressor.  I cut a square out of the teak under the settee and mounted the control panel down low, close to the compressor but where I could see it clearly.  There is a space under the floorboards near the mast that has about 24 inches of clearance.  That worked well for the pre-filtration system and the post treatment.  Back in the galley I had an unused thru-hull so that’s where I put the sea strainer and boost pump.  

 

Thru hull, strainer, and boost pump

So here is how it works.  The sea water comes into the boat through a valve.  It passes through a strainer and goes to a little pump that gives it some pressure to push the salt water through the various filters.  The pressurized sea water goes through a 20 micron filter then a 5 micron filter.  Now it is pretty darn clean.  But wait. Sometimes you want to back flush the system with clean water so we also mounted a fresh water carbon filter that you can switch on when you want to flush.  The carbon filter uses clean, not salty, water from the fresh water tanks to flush the system.  Carbon removes chlorine.  There is a hint of chlorine in our 150 gallon water tank.  Chlorine harms the reverse osmosis membrane so it has to be removed if flushing with dock water or other chlorinated water.  And then when you leave the water maker unused for the summer you have to push a pickling solution into the membrane.  So we have a valve and hose to do that.  To summarize, there are three options providing liquid to the pump and membrane:  The filtered salt water, for making water, the fresh water rinse with chlorine removed by the charcoal filter and the connection to the pickling solution for when you want to store the water maker for the summer.  

After all that foldoral and fiddle dee dee the water gets to the big mamma high pressure pump.  This is a big dog of a unit sucking 20 to 38 amps per hour, depending on how far you turn the pressure valve.  The pump pushes the salt water into the membrane.  If you choke the exit of the membrane tube with the pressure valve it forces the water through the membrane instead of bypassing to an exit.  Only pure water can go through the membrane.  The salt stays and is carried away with the reject salt water.  What comes out of the membrane tube is one hose carrying very salty water and one hose carrying 100 per cent fresh water.  The salty water goes down the drain and back to the sea.  The fresh goes to a little faucet at the galley sink where you let it run for a while and you taste it to make sure it is good. Then you flip a valve and the water is diverted into the 150 gallon fresh water tank. 

The result?  Clear, clean, water........ water

We took about four days to hook everything up, taking our time to make sure everything was connected properly and that the layout was as straightforward as possible with few hard bends in the hoses and no place for air pockets to form.  Since we were deep in the bilge we found lots of other things to do, removing extra wiring and cleaning up things.  Connie became the hose installer with her head down in the bilge or under the sink running the low pressure hoses and pulling electrical wiring. 

We fired it up this afternoon and let it run for a while to get all the air out of the system and then it started cranking out pure fresh water.  High Fives! We bought the 260DML unit that can run at 13 gallons per hour at 38 amps and when I cranked the pressure valve, sure enough we got 13 gallons per hour output.  But, as Will had said, we could adjust the pressure valve and drop down to 8.5 gallons per hour and the draw goes down to about 20 amps.  

With the solar bringing in about 15 amps on a sunny day we can run the water maker with about a 10 amp deficit making 8.5 gallons per hour.  (The refrigerator and other systems will be drawing about 5 amps.)  When we are motoring (and have lots of power) we can ramp it up to full capacity and make 13 gallons per hour.

So far, so good.  We are another step closer to being off the grid.  Our solar panels are providing us with lights, navigation, refrigeration, and now water.  We are only carbon hogs when motoring the sailboat or running the outboard engine on the dinghy.  But more importantly, we can say goodbye to marinas and fuel docks where we usually fill our water tanks.  We can go up into the Sea of Cortez or across the Pacific Ocean for that matter and not worry about water water everywhere but not a drop to drink!