Lagoon 450 F achieves watermaker redundancy with Rainman (French Polynesia)

lagoon 450 watermaker raroia french polynesia
Lagoon 450 F at Raroia Atoll, French Polynesia

Here is an informative story from Martin, a Danish Rainman customer that inherited one Rainman on a used boat, then ended up purchasing two more Rainmans on his newer boat. One portable and one installed, providing full watermaker redundancy.

Customer Story

I sailed from Denmark in 2017 in my 40 foot monohull, an Aphrodite 40 from 1986. I was 27 years old and had planned to sail around the world for about 3 years. I had spent a lot of time and money to outfit the boat for this trip. A watermaker was of course part of the plan, but back then I was not aware of how much water a cruiser actually uses. Back then I chose a [energy recovery watermaker brand]  30 litre/hour, 12 volt. That fit my budget at the time, and the 12 volt low consumption was good for my old boat. The boat only had 400 AH of gel batteries with 400 watts of solar. Power availability was limited.

After 1,5 years sailing from Denmark down the coast of Europe to the Canaries and on to Capo Verde, we crossed the Atlantic in December 2017 and began to really use the watermaker. After some months in the Caribbean we began to have some issues with the watermaker, losing pressure and it developed a few leaks. Eventually crossing to French Polynesia from Panama, I decided to upgrade to a bigger watermaker. I actually ended up making a much bigger decision. Taking the step from sailing for a limited period of 3 years, to saying I wanted to do this for as long as I could. I sold my boat in Tahiti and used all my savings to buy a 2017 Lagoon 450F that was also in Tahiti. I bought the boat and it already had a Rainman 12V 30 litre/hour watermaker on it that was two years old. It was a good machine with no problems, but on the new boat I had paying crew of 3-6 people on board. With my rule of using the boat as my home, keeping saltwater in the sea, having a clean ship, washing machine, dishwasher, etc., I decided to upgrade for a new Rainman 220VAC 140 litre/hour. I purchased it in Fiji six months after I bought the boat. It took me an hour to semi install it with seawater intake from a through hull, but still having the brine and product water as loose hoses.

lagoon 450 f redundant rainman watermaker
Redundant Rainmans – Note the intake hose on cased system is plumbed in

Now we are in French Polynesia again, and after 4,5 years of cruising I decided to do some upgrades. One of the things as a full time cruiser is that sometimes you can go around and worry about if the engines fail in a rough passage into the atolls, or the generator works tomorrow, or the watermaker. Even though they may be new, things can fail. On a couple of friends’ boats they have had problems with their generators and watermakers amongst other things. Furthermore, because of our water consumption I was tired of going outside to the locker on a daily basis to put the hoses down and turn the watermaker on. I wanted the convenience of a Rainman Naked with Autoflush and Control Panel.

My idea was that every time we run the engines or the generator I want to quickly and easily turn the watermaker on and make as much water as possible. Just for maybe 30 minutes while charging the batteries, I could easily turn the watermaker on and make another 70 litres of water, where before I sometimes did not want to do that because it was a hassle or the weather was bad. I also wanted to be able to double the amount of watermaking if necessary, so we might run the generator with both Rainmans and produce 280 litres/hour. After a trip with a lot of saltwater spray, we wash the boat from top to bottom and wash some clothes, which might use 600-700 litres of water. By the time we are done cleaning, our tanks are almost full again, without too many hours on the generator.

Then for my stomach and stress level, its amazing to have two units in case one fails. I can’t overstate how much that extra unit has done for my peace of mind. Our boat is kept in mint condition with very few brake downs, but every time I can eliminate a problem by having redundancy, I prefer to do it. My next project is to eliminate the use of a generator.

The new Rainman Naked is fully installed into the boat and I love it. It is fitted with the Control Panel and Autoflush as well. The pressure supply units are installed forward of the salon, before the trampolines, in a storage compartment which many uses for fenders, ropes etc. I find the room perfect for the units. I can get down there very easily and it’s an outside “wetroom” (it’s never wet, but it can take it much better than the inside of the boat). If any spills are made doing maintenance or changing filters, I simply rinse it with freshwater and wipe it up. The membranes fit perfectly out there too, leaving plenty of room for our tools. The big plus is that the noise is kept outside of the living area. The distance from the HP pumps and membranes are under 1,5 meter to the through hulls and control panel. It was surprisingly easy to install because my Lagoon already had a tube with freshwater hoses going to the deckwash outlet at the trampoline. While I am sitting here writing this, the Rainman is running and the sound from it is not at all irritating. It’s good because it’s the sound of a healthy working machine on Casablanca.

lagoon 450 f watermaker rainman control panel
Rainman Control Panel Installed On Lagoon 450 F

Our monthly consumption is 7000 litres of water, 6-8 people on board and never in a marina. This includes drinking water, washing clothes (20-40 loads per month), washing of the boat, rinsing the dinghy after each trip if windy and big waves, etc.

We even help other cruisers. About a month ago, a fellow cruiser’s watermaker broke down with ten people on board. We delivered 500 litres of water by an extension hose while at anchor. Its amazing to be able to do that.

We have just signed papers on a new Lagoon 50 with delivery from factory in a year. We are installing same Rainman watermakers, maybe 2 naked installations fully installed with control panels for them both. Lagoon only gives the option for a 100 litre/hour watermaker, which is too small for us. The redundancy is important to me. I would rather have two units than one big one, in the same way I like the fact that the cat has two engines.

lagoon 450 f cruising romance proposal
Good spot for a proposal
Love Story Footnote

When I left Denmark in 2017, I sailed alone. When I arrived in Tahiti for the first time 2018, I met Ann. Two years younger than me, she was also sailing in her own boat with one crew onboard. We continued to sail together side by side all the way from French Polynesia through Niue, Tonga, Fiji, Vanuatu, Papua New Guinea and on to Indonesia. We then decided to move in together. Selling her boat and sailing straight back (Corona virus closed many borders) to French Polynesia upwind. 6500 NM and 8 weeks later we were in French Polynesia again. Our home. And I asked her to marry me.

lagoon 450 f marriage engagement yacht
Martin and Ann


Helpful Links

» Product information: Rainman AC (Electric) desalinator

» Rainman Control Panel

» Rainman Autoflush System

» Iaorana Yacht Services – French Polynesia

» Rainman watermaker dealers in Oceania