Desalinators for Boats: Expert Guide and Recommendations

Dessal

⏳Estimated reading time: 5 minutes⏳

Quick Summary

A marine watermaker or desalination system is a reverse osmosis system designed to convert seawater into potable water on board. The correct choice primarily depends on the boat's length, the number of people on board, the available energy consumption, and the usage profile (coastal, long-distance, or oceanic cruising).

What is a boat watermaker and how does it work?

A marine watermaker is a water treatment device that uses reverse osmosis (RO) to remove salts, microorganisms, particles, and even contaminants from seawater, producing safe drinking water for consumption, cooking, and hygiene on board.

To learn more: reverse osmosis.

Which watermaker to choose according to boat type?

1.      Boats up to 10–12 meters (1-4 people)

Technical recommendation:

  • Production: up to 35 l/h
  • Power supply: 12 V or 24 V DC
  • Typical use: couples or small crews (1-4 people)

DESSAL experience: For these types of boats without an onboard generator, prioritizing low consumption and system reliability is key. Here, we unequivocally recommend a SolarMaax 200 (32 liters/hour) energy recovery system, manufactured in Canada.

2.      Sailboats and catamarans 12–16 meters (4-8 people)

Technical recommendation:

  • Production: 35–50 l/h depending on number of occupants
  • Power supply: 12 V / 24 V DC
  • Typical use: medium and long voyages

DESSAL experience: Here, the balance between production and consumption is essential. Our recommendation here is a SolarMaax 340 (53 liters/hour) energy recovery system, with the improved Clark pump.

3.      Vessels 18-26 meters (4-12 people)

Technical recommendation:

  • Production: 50-150 l/h depending on number of occupants
  • Power supply: 12 V / 24 V DC or AC with generator
  • Typical use: medium and long voyages

DESSAL experience: If consumption is the priority, the recommendation would be a SolarMaax 750 (118 l/h). If you have a generator, our recommendation will be the same as in the next section.

4.      Vessels over 26 meters or intensive use (more than 12 people)

Technical recommendation:

  • Production: >150 l/h
  • Power supply: AC with generator
  • Typical use: charter, professional use, large crew

DESSAL experience: When the sailing program is international, the budget allows it, and a fully automatic 230 V watermaker is sought, priority is usually given to equipment from manufacturers with a consolidated global presence. In the field of watermakers for boats, similar to the automotive sector, users often clearly identify with certain manufacturers. In this regard, some may opt for an Aquamatic from Sea Recovery or a Legend from Blue Water, both manufactured in the United States. Their main added value lies in the wide international availability of spare parts and the ease of finding technical service in different parts of the world, an especially relevant aspect for long-distance navigation.

For those who sail mainly in Spain and Europe and are looking for a robust, reliable solution with an excellent quality-price ratio, DessaLine is a highly recommended alternative with its manual or semi-automatic models. The brand has a wide network of nautical businesses and collaborators in Spain, offers remote technical assistance, and provides specialized training in marine watermakers, facilitating both commissioning and long-term maintenance.

Common mistakes when choosing a marine watermaker

  • Buying solely on price without considering electrical consumption
  • Underestimating the actual fresh water production needed
  • Ignoring the availability of technical service
  • Not adapting the system to the navigation profile

According to the experience of DESSAL Marine Tech, a specialized distributor for over 20 years and a manufacturer, more than 60% of serious breakdowns are due to poor initial equipment selection, inadequate installation, or very deficient maintenance.

Why are technical service and real experience key?

A watermaker is not a household appliance: it is a critical system on board. In navigation, the difference between theory and practice is enormous.

DESSAL Marine Tech:

  • Designs and manufactures its own systems
  • Is an authorized technical service for leading brands
  • Installs and maintains equipment on real boats
  • Adapts each system to the specific vessel

Frequently asked questions:

·         Which watermaker is best for a sailboat?

The best watermaker for a sailboat is a low-consumption DC reverse osmosis system, correctly sized according to length and crew, and installed by a specialist with real marine experience.

·         Which watermaker is best for charter?

Here, the comfort of the crew must be prioritized. For productions starting from 150 liters per hour, we recommend a 230 V watermaker with piston pumps.

·         How much water does a marine watermaker produce?

From 30 l/h on small boats to more than 300 l/h on large vessels or for professional use.

·         Does a watermaker consume a lot of electricity?

Not necessarily. Modern, well-designed systems can operate with consumption compatible with solar panels and adequate battery banks.

Expert Conclusion

The best watermaker is not the most powerful or the cheapest, but the one best adapted to the boat, its use, and the available energy. DESSAL Marine Tech always recommends a personalized selection over standard solutions.

The recommendations in this article reflect the technical judgment of DESSAL Marine Tech, specialists in marine watermakers and onboard water treatment for over two decades.

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