I have had both DC and AC powered watermakers, and used both of them extensively for years each. In fact I have not taken on dock water for probably 5 years now of “stay aboard” status. Not full time, but not a weekend warrior either.
The DC model was a Katadyne unit. It was very reliable and produced about 7 gallons per hour.
The AC model was put together using off the shelf parts. It was engineered and marketed by Cruise RO. It produces 40 gallons per hour.
Lets get the DC vs AC issue out of the way up front. I see ZERO advantage to a DC watermaker for any boat that has a decent reliable generator. No ambuguity here, Zero advantage of DC.
Why??? Thats simple. DC watermakers are low output. That means you are going to have to run that watermaker more than you probably want to hear it. Yes you can hear the watermaker running. My Katadyne DC unit was louder than my generator. It was a single piston design and you could hear it “thump, thump, thump” when running. Yes AC watermakers are also noisy. My AC watermaker is about the same level as noise as my Northern Lights Generator. The differencer is that I can make in an hour what it takes all day from the DC unit.
I can also run my watermaker from my inverter and actually do that when underway quite a bit.
The question then becomes modular or stand alone. Stand alone systems are GREAT. Hook up the inputs and outputs and you have water. How cool is that! The devil is in the details though. Stand alone units have all the controls on the front of them. Do you have a place to put it where you are comfortable getting to the front every time you turn it on or off? Do you want to crawl into some deep dark place every time?
Yes you can get a standalone model with a remote panel. That is fantastic, but it comes with a price. If you go with a standalone model and a remote panel just make sure the model you get has a high pressure adjustment capability either automatic or from the remote. This is critical and is more expensive than one might imagine.
The other choice is a modular unit. With these you get separate components that you plumb and wire together to make a watermaker. This allows you to have your panel anywhere you can get hosers and electrical to. This also allows you to be creative with your component placement.
The challenge to a modular system is you are going to have to be more technically inclined than with a standalone system. The work is not all that difficult, but it is work involving plumbing, and wiring, some of it high pressure plumbing.
I opted for a modular system. I am technical by nature and found that it was pretty enjoyable to install, and learn how watermakers work. I installed my panel in the salon because I use it every day and I didn’t want the trouble of moving stuff out of the way to get to the lazarette, or to get down into the engine room just to make some water.
I opted for a 40 gallon per hour unit because I knew from my Katadyne watermaker experience that my usage is about 40 to 50 gallons per day. Yes we like to take showers every day. Yes we like to do dishes and not have to be concerned with turning off the water while we brush our teeth. We also fish and like keeping the cockpit clean using nice fresh water.
We also like clean clothes, so the onboard washing machine gets used frequently.
I also opted for a unit that has zero proprietary parts. Why? that is simple. I do not want to be dependent on my watermaker manufacturer for the rest of the units life. I want to be able to shop for replacement parts where I want to shop for them, and not be locked in to any one brand.
Who did I buy my system from? Rich over at Cruise RO that’s who. Great small business run by a cruiser who uses his products and cares about his customers.
