3 Best Watermakers for Sailboats (Reviews & Buying Guide)

best watermakers for sailboats

With a boat surrounded by water, there’s surely no such thing as dehydration out on the sea. Right? Well, not exactly. There’s way too much salt in seawater, and your kidneys would have to work overtime to filter it out. And to do that, they would need more water, which explains why copious amounts of seawater is toxic to humans.

So before you take a sip of that salty brine, why not pass it through a watermaker? The best watermakers for sailboats can take seawater and turn it into potable drinking water, giving you an infinite water supply to keep you hydrated and healthy on extended excursions.

What is a Watermaker?

Otherwise called a ‘desalinator’, a watermaker takes salty seawater and passes it through a process called reverse osmosis. This happens by pushing the water through a semi permeable membrane that allows the water molecules to pass through, but restricts salt, bacteria, and other organic material.

The clean, drinkable water is then passed into a water tank where you can then collect water for use. The remaining brine that was left during filtration is then tossed overboard and discarded. What’s nice is that these machines don’t use any chemicals, so there’s no risk of water contamination or pollution.

Some machines also use a pre or post treatment of the water using things like filters, sand, activated carbon, remineralization, or microfiltration to guarantee safe drinking water.

The Benefits of Watermakers

watermaker for sailboats

Modern-day technology has made it possible for manufacturers to develop more compact, efficient watermakers than ever before. This has also significantly driven down prices, making them far more accessible to sailors of all backgrounds.

Today, watermakers are recognized as a sailboat essential, especially for people who frequent the waves for long periods of time. Some of the benefits of these machines include:

Efficient Speed and Fuel Consumption

Yes, you read that right. Consider this - just 1 gallon of water weighs 8.3 pounds. If you’ve got 10 gallons on board, that’s equivalent to 83 pounds. A hundred gallons, and you’ve got an extra 830 pounds on board.

Watermakers allow boat owners to shave down their total weight. This lets you sail more efficiently, allowing faster speeds and lower fuel consumption which is important when you’re planning to sail long distances.

More Floor Area

Without a watermaker, you’d have to find room on board for the several tens or hundreds of gallons you need to bring with you. That also entails finding a place on your boat to store these water vats, which would obviously require significant room.

The watermakers of today are compact and lightweight. They can be either modular or self-contained, giving you different options to match your boat’s floor plan and use as little space as possible.

Safe Sailing

To ensure safe sailing, some studies have found that dehydration might actually be the reason for poor sailing performance. With dehydrated captains feeling lightheaded, achy, tired, and confused, it becomes increasingly likely to run into an accident that could endanger the lives of the people on board.

A watermaker guarantees that there will be fresh potable water at the ready any time you might need it. This doesn’t only curb the chances of dehydration, but also provides a solution for a variety of health conditions including diarrhea and various types of infections.

Extended Sailing Duration

You’ll only be able to sail for as long as your supplies on-board last. As your drinking water runs low, you’ll find yourself having to find the nearest dock to replenish supplies every so often. That’s if there are docks and shores you can access throughout your route. But what if there aren’t any?

Having the necessary equipment on board to extend your supply also means that you won’t have to rely on on-shore facilities to see you through your trip. This gives you more independence and flexibility as well as reducing the need to calculate complicated logistics.

Easier Boat Maintenance

Whether you’re underway or parked at the dock, your watermaker can help streamline boat maintenance by bringing freshwater straight to your vessel. With no need to collect buckets of water to lug back on board for a washdown, you can cut back the time and effort it usually takes to keep your boat clean.

Lots of boat owners even use their watermaker to give their boats a quick clean while they’re out at sea. This helps get rid of accumulated filth and dirt, reducing the need for a tedious deep clean once you get back to the dock.

The 3 Best Watermakers for Sailboats

Back in the day, watermakers were a luxury for the rich and the capable. But today, they’re incredibly affordable and easily accessible. Needless to say, manufacturers have also taken liberties with designing their own machines.

For you, that means an endless list of watermaker bets that could easily screw up your choice. So to help narrow down your options and lead you to the right one, here are our top 3 vetted picks:

1. Katadyn Power Survivor 40E Watermaker Desalinator

katadyn power survivor watermaker desalinator

Small yet powerful, the Katadyn Power Survivor 40E is a reliable workhorse designed for boats with a small crew population of 2 to 3. This modular unit provides 1.5 gallons of water per hour, and draws only 4 amps from a 12-volt system, making it one of the most energy efficient desalinators out there.

This ‘Energy Recovery’ system works to desalinate seawater at just a fraction of the energy used by other watermakers in the same segment. Thus the device gets its name: Power Survivor.

Silent and lightweight, the machine lets you separate its primary system components so you can install the device seamlessly even in tight or awkward, irregular spaces. Most of its parts also come with a 3-year warranty, giving you that extra peace of mind versus damages and malfunctions.

AMPAC USA SeaPro Saltwater Desalination RO Watermaker

Able to produce 100 gallons per day, this watermaker was designed for use on small power boats or sailboats. Its super quiet automatic operation features intuitive controls that let you start and stop the desalination process with the push of a button.

Equipped with a noise pulsation dampener, the sounds produced during operation are negligible at best. This lets you run the machine in the evening to store up clean water for the next day without having to disturb your crew’s peace and quiet.

For boats with limited space, the SeaPro comes in a modular design that’s perfect for tight floor areas. It also comes in a partially mounted compact frame option that lets you fit the desalinator in place with little time and effort.

Rainman 12 Volt DC Watermaker

According to Rainman, their 12 Volt DC Watermaker consumes the least energy, able to filter 9 gallons of water per hour. The design touts a two-part system -- one pressure supply unit and another reverse osmosis unit. The former lifts the seawater from the source, while the other performs the desalination process.

What’s unique about Rainman’s watermaker is that the design gives you the option to install the unit directly to your boat, or to keep it handy as a portable watermaker system. This offers immense flexibility, allowing you to set up or take down your system as your situation calls for.

Aside from all of that, the Rainman Desalinator also features a streamlined control panel that makes everything easy to understand and operate at a glance. It also comes equipped with its own LED salinity sensor that tells you when water is good enough to store in your tank.

Choosing the Right Desalinator Watermaker

Not quite sure which one is right for you? Here are a few factors worth taking into consideration when buying a watermaker.

Size and Installation

There are two major options: modular and self-contained. The modular system lets you take the unit apart to install each part at a different part of your boat. This one’s ideal for boats with limited space. The self-contained system has the entire unit built together, which means it has to be installed as one piece.

Gallons Per Hour

How big is your crew? More people means you might need a watermaker with a higher GPH. Smaller machines capable of 1.5 to 2 GPH might be good for crews of 2-3 persons. But larger boats may need several hundreds of GPH to meet all of the crew’s needs.

Non-Proprietary Parts

You’re going to make part replacements one way or another. See to it that you’re buying a machine that uses non-proprietary parts so you can purchase the necessary replacements anywhere online.

Warranty and Services

In case anything happens to your watermaker, who will be there to help you fix it? Check the warranty coverage and see how long the manufacturer is willing to cover it for damages and malfunction. It’s also important to make sure there’s a nearby service center to cater to your needs in case of damage.

Water You Waiting For?

The best watermakers for sailboats offer to give you a virtually endless supply of clean drinking water when you need it. But there are a ton of choices on the market, so it pays to know what you’re getting before you shell out that cash. Consider our bets for the best desalinators for your sailboat, and keep your crew happy, healthy, and hydrated all along the way.

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