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In this article, we dive into our experience with boat watermakers aboard Satori. In particular, the Rainman High Output watermaker and the legacy Little Wonder 200gpd unit. We also took Rainman’s challenge to go from fresh out of the box to making fresh water in 10 minutes!

In this article, we will cover:

  • Rainman’s deal for Sailing Satori viewers
  • Our experience with the legacy Little Wonder watermaker
  • Effects of making water on our boat systems
  • Why we chose the Rainman High Capacity unit
  • (Video ) 10 Minute Challenge; Kelly vs. Rainman
  • Pros and Cons of Rainman High Output unit
  • Our Future watermaker plans

Rainman Satori Gift Pack – Over $100 value!

Since the release of our 10-minute Challenge Video, we have worked out a deal with Rainman’s distributor out of Florida, SeaTask. They are offering all Sailing Satori viewers a special gift pack any Rainman System, worth over $100!

Enter promo code SATORI and automatically get 5 spare pre-filter, a TDS meter, and a Rainman t-shirt.

Click here to see what they offer –  SeaTask Group – Rainman Watermakers

Full Video

Something You Should Know

Before I get into reviewing the Rainman Desalinator, it’s only appropriate that I take a step back in time, and share my experiences with our old watermaker. Yes, I had a watermaker before the Rainman. For many cruisers, just the idea of having a water maker is a luxury. If you don’t want to read my little history lesson, I’ll tell you that this thing is awesome. The last time I measured; we were getting 36 gallons of fresh water per hour. But it’s not perfect either. It’s somewhat big and heavy, two significant challenges on a sailboat. We also have to run the generator every time we use it. The loud, smelly, neighbor-terrorizing generator.

Picture of Rainman watermaker

Rainman setup on Satori’s aft deck

I will be completely honest and tell you that we are not good at conserving water. I mean we try, but it just seems to disappear, evaporate, aliens beamed it out of our tanks at night…who knows! It just means we have to run it more often. For our old 12V unit, this means we would run the batteries down, and the fridge would die. For the Rainman, this means I have to haul it on deck and set it up more often. Big, heavy, work, lazy. It sounds like a drag doesn’t it? Well, not really.

Little Wonder

When I bought Satori (2014), a 1989 Morgan 44 Sailboat, she came equipped with an older model water maker (12V Little Wonder 200 gallon per day), which was installed in 1999. For the first few years of dock life, I didn’t have much use for it. In the back of my head, commissioning the existing water maker seemed like a huge task. I knew it had not been used for at least five years, and I had no idea if it had been properly pickled. Satori holds over 200 gallons of fresh water, so my weekend trips along the gulf coast of Florida and the occasional trip to Key West meant that it would stay unused

Picture of little wonder pressure pump installed under sink

Little Wonder Pressure pump installed under sink

In 2017, the goal of full-time cruising was the light at the end of the tunnel, and the light was blinding us. This meant it was time to dust off the old water maker and see what this thing could do. It was at this time I realized that I had no clue how it worked. The unit was installed partly under the galley sink, and partly in the main bilge area. The feed hose was run to the bow, where is shared a seacock with the front head. There was a spaghetti mess of stiff, 20-year-old hoses that I knew nothing about. Though I did know they always seemed to be in my way.

Shakedown Shakeout

After a little light reading (the manual), I was able to replace a few hoses and make some sense of things. After a call to the local distributor, I was surprised that he told me to just fire the damn thing up, right there in the marina. Sure enough, with that old membrane and my hack-plumbing job, it was making water! Pretty good water too, around 500ppm. That was very encouraging!

picutre of Little Wonder pressure vessel installed under sink

Little Wonder pressure vessel installed under sink

Before we started fulltime cruising, we did a two-week shakedown trip from Tampa Bay to Key West and the Dry Tortuga Islands. This was the real test of the water maker… not to mention my entire electrical system. The Little Wonder continued to make water, though the quality of the water slowly decreased throughout that trip. By the end, the water quality was over 1000ppm. It was borderline Drinkable and not that enjoyable. But this told me what I suspected for years. I needed a new membrane.

Cruising for a Bruising

Fast forward six months, and we had started our cruising journey. We survived Irma in Fort Myers Beach and were on our way south. I waited until now to install the new membrane because I knew it would not get much use while we were still at a dock. You think you know your boat, but you don’t! Not until you spend at least six months disconnected from shore. This was when the systems began fighting each other.

Solar vs. Batteries vs. Refrigerator vs. Water maker!

We were undersized on solar (250 w), our batteries were old and acting half their size (2 – 4D Gel 350 ah total), the refrigerator ran seemingly non-stop (Danfoss BD50 icebox conversion unit), and the watermaker needed to be run 2-4 hours every day. It’s a vicious cycle, run the water maker, even at high sun, and you steal all the juice the batteries needed to recover from the night before. This causes the refrigerator’s low-voltage protection to kick in, and the freezer thaws all of your Hungry Man TV dinners you stashed for your Gulf Stream crossing. Maybe you shouldn’t have spent your sleepless night binging on Golden Girls re-runs on YouTube.

picture of man replacing membrane on Little Wonder watermaker

Nick replacing membrane on Little Wonder

We replaced our batteries in Marathon, Florida and upgraded solar in Luperon, Dominican Republic. The struggle got better but remained. Kelly’s FOWO (Fear Of Water Outage), was in full effect. We got better at conserving, but it’s not one of our strong points. We know cruisers that claim to go a month on 50 gallons. That seems insane; I think we drink more than 50 gallons a month!

Not Enough Water!

I spent a month with just me on board, and the water maker was perfect. I’d run it every other day for a couple of hours. If you do the math, you would think that adding one more person (and a 5 lb Chihuahua) would only mean running it every day for a few hours. But for some reason, it doesn’t work that way. Add a Girl to the equation, and the shower factor goes up exponentially. Yes, she insists that I shower every day, at least when we’re in close quarters. Then you have her “hair washing” days, dog baths, proper meals, the addition of dishwashing, etc.

A single dude or couple of dirty hippies doesn’t need a water maker, no offense to the clean hippies. But we said from day one that we wanted this to be a comfortable lifestyle. We are in this long term, so we wanted to live a step above glorified camping. The most significant factors contributing to the “camping feel” is access to water, electricity, and laundry. A watermaker, or should I say, the right water maker can help solve all of these problems for us.

Rainman Watermaker

While cruising, one of our buddy boats (Valhalla) had a Rainman. I already knew about the Rainman, and it’s over 30 gallons per hour capacity, but I was all about the everything being 12 volts and running off solar, even though Satori came equipped with an 8KW diesel generator. Rainman is set up as a portable system, designed to run off of a 2000W generator.

picture of girl turning on the Rainman Watermaker

Kelly doing the honors – flipping the switch on the Rainman Watermaker

They would store the two unit system in an unused berth, then pull it out once a week to fill their tanks using their Honda generator, then store it again. One of the draws of this system is that there is no installation required. We were envious! Even if they completely ran out of water in their tanks, they could be showering again in 10 minutes! With the way the system is set up, we could have just borrowed it from them for a few hours, a novel idea! But alas, I was too proud.

Picture of girl holding a drill on a sailboat (Satori).

Kelly ready to take the 10-Minute Challenge!

After our first season cruising, we put serious consideration into upgrading to the Rainman. Flat out, water makers are expensive! Some fully automated units can run as much as $15,000. Another draw to the Rainman system is that it is one of the most affordable units on the market at $5000 for the high capacity unit. Surprisingly, these machines can be quite simple, and that’s precisely how Rainman has kept their price relatively low. Just as a comparison, the newest version of our installed Little Wonder 5-6 gallon per hour unit costs about the same as the Rainman 30 gal per hour unit. Chalk it up to the “marine” marketing system. If it’s for a boat, triple the price. It appears that Rainman has bucked the trend in this respect and created a quality product at a fair price.


By the writing of this article, we have been using our Rainman for about two months. We love it, but like anything else, it’s not perfect. Here is a list of our Pro’s and Con’s:


  • It’s Fast – 100 gallon in about 3 hours. Yes, please!
  • The Price – Compared to other like products on the market.
  • Easy to Use – No frills, no fuss.
  • Sexy – The cases are sleek and good looking.


  • Weight – This may be the case with all watermakers, but it’s probably more noticeable in the portable unit.
  • Size – It’s pretty big, so you need to have space onboard. Luckily it comes in 2 pieces.
  • Generator – it has to be run with a generator, though Rainman makes a 12v version but it doesn’t have the same capacity.
picture of rainman wateramaker in sailboat head with hoses running out the window

Rainman watermaker setup to run inside with hoses out the port window

The Rainman gets high marks in our book. Our biggest complaint is not the setup specifically, but instead hauling the two bulky cases onto the deck. We began running all the hoses out the portlight, which made the process much more manageable. Now, we have taken that experiment and expanded on it. We have decided to take our guest head, located in the v berth (take a tour of our boat here), and converted it into a watermaker room. And with all that water making ability, we have also added a compact washing machine.

Rainman Satori Gift Pack – Over $100 value!

Since the release of our 10-minute Challenge Video, we have worked out a deal with Rainman’s distributor out of Florida, SeaTask. They are offering all Sailing Satori viewers a special gift pack any Rainman System, worth over $100! Enter promo code SATORI and automatically get 5 spare pre-filter, a TDS meter, and a Rainman t-shirt. Click here to see what they offer –  SeaTask Group – Rainman Watermakers

The Future for Our Rainman Watermaker

Yes, we build a laundry room on our boat! In the weeks to come, we will create a video and an article about our laundry room conversion. Make sure you subscribe to our YouTube channel and sign up on our mailing list. You’re going to want to see this!

picture of rainman watermaker and washing machine installed in a sailboat bathroom

Satori’s installation of Rainman watermaker in the converted laundry room

10-Minute Challenge – Video Transcription

Intro (Rainman Watermaker)

Hey, guys, I’m Nick and today we’re talking about the Rainman water maker. This desalinator takes seawater and turns it into fresh drinking water. This beast makes 30 gallons an hour. We’re going to challenge Rainman’s claim that you can go from fresh out of the box brand-new unit to making fresh water in 10 minutes. Keep watching! (Rainman Watermaker)

Nick discussing the Rainman Watermaker

Right out of the box Rainman appears to give you everything you need. There’s not any additional pieces or installation needed. That’s kind of the draw of this unit. The only setup you need to do is to replace the oil plug with this, which is like a breather plug. My first impressions are that it’s an attractive setup. I like the plastic casing. I like how everything’s clean and neat and setup in just two units. There are no sharp corners. Everything’s pretty easy, and the handles are built right in.(Rainman Watermaker)

The thing I am surprised about is it’s heavier than what I expected and a bit larger as well. So now when I’m thinking about where I’m going to do my semi-permanent install, I’m going to have to think about it a little more. Some of the spaces I hadn’t intended in storing this won’t work. So I’m going to have to get creative. Pulling this thing in and out of a cramped space or in and out of the companionway which can get a little bit narrow. It’s not something I would want to do every day. Which is why I think it’s good this thing makes so much water so quickly. It’s kind of a thing you can do once a week if needed. Also, it’s a motivation to get this thing installed. (Rainman Watermaker)

Nick explains how the Rainman Watermaker works

You have the pressure unit that is a pressure washer pump. It feeds the Membranes, which are the pressure vessels where the water gets filtered. Inside the high capacity unit, we have two 40 inch membranes. It also comes with all the hoses you need. The gauge is already attached and some optional mounting hardware if you want to do a permanent or semi-permanent install like I plan to do. (Rainman Watermaker)

Time to test the machine!  (Rainman Watermaker)

All right so it’s time! We’re ready to use this water maker for the first time. We’re going to challenge Rainman’s claim that you can go from brand-new out-of-the-box water maker to making water in how long? Just 10 minutes! 10 minutes! It’s actually super easy. The set up from when you get it new is almost the same as any other time you use it except for you have to change an oil plug in there. We’re going to test it anyway. going to find out if we can do this. We’re going to have Kelly do the whole thing by herself. Why is that funny!(Rainman Watermaker)

Well Kelly’s not the most mechanically inclined so it might be easier if I did this.10 minutes is probably no problem but we’re going to test how easy this product is to use with Kelly behind the wheel of it. Nervous? No! Do you feel pressure? Maybe a little. I’m not super confident but okay. If I’ve done it before, then it would be no problem, but this is my first time. I’ll help I’ll coach you. Okay! (Rainman Watermaker)

Nick explains what to do  (Rainman Watermaker)

Here are all right the tools that you need for the job. You’re going to need this wrench and this replacement plug. Then that drill behind you with the screwdriver bit. Okay, so first step is to replace this breather plug. There’s a little access panel. Open that up, change the plug, and then you connect the hoses for the system. (Rainman Watermaker)

Do I need this right now? You will after you open that up. Then you connect all the hoses and plug it in. I brought an extension cord over there so you could just plug it in. The generator is already running. I don’t know if that’s cheating or not? We already got the generator running so you can just plug it in. This thing runs off typically a Honda 2000 generator, but we have an onboard generator. We’ll start the timer. On your mark, get set, go! (Rainman Watermaker)

After the 10 Rainman Watermaker minute challenge

Now we have water coming out! Did I do it? I think you did it! Nine minutes and 20 Seconds! Oh yeah! So that was super easy! I’m surprised actually how simple that was and how simple this machine is to use. We’re going to do an install. What I call a soft install. In the weeks to come, I’m going to transform our front bathroom, our unused guest bathroom too, wait for it. Oh, a water maker/laundry room! Subscribe now if you haven’t already, hit the little bell, so you get a notification because you’re going to want to see our laundry room conversion! That’s right, a sailboat with a laundry room! (Rainman Watermaker)

10 Minute Challenge! Kelly vs. Rainman Watermanker! (Sailing Satori) OTH:8