Choosing the right watermaker for your boat
Choosing the right watermaker for your boat

Ensure a reliable source of fresh water while sailing by choosing the right watermaker for your boat. Our guide covers the different types available, factors to consider, and tips for installation and maintenance.

Choosing the Right Watermaker for Your Boat

As you embark on your sailing adventure, one of the most important considerations is ensuring you have a reliable source of fresh water. While you can certainly stock up on bottled water or rely on rainwater collection, a more sustainable and convenient solution is to invest in a watermaker. In this article, we’ll explore the ins and outs of watermakers, including the different types available, factors to consider when choosing one, and tips for installation and maintenance.

What is a Watermaker?

A watermaker, also known as a desalinator, is a device that converts seawater into fresh, potable water. It does this through a process called reverse osmosis, which involves forcing seawater through a semi-permeable membrane that filters out salt, bacteria, and other impurities. The result is clean, fresh water that’s safe to drink, cook with, and use for personal hygiene.

Types of Watermakers

There are several types of watermakers available, each with its own set of advantages and disadvantages. The main types include:

Manual Watermakers

Manual watermakers are the simplest and most affordable option. They require no electricity and are operated by hand, making them ideal for small boats or as a backup system. However, they have a low output, typically producing only a few liters of water per hour, so they may not be suitable for larger boats or families with high water consumption.

Electric Watermakers

Electric watermakers are the most common type found on cruising boats. They run on your boat’s electrical system and can produce a much higher output than manual models, typically ranging from 20 to 200 liters per hour. However, they can be more expensive and require a reliable source of power, which may be a concern for those relying on solar or wind energy.

Engine-Driven Watermakers

Engine-driven watermakers are powered by your boat’s engine, making them a good option for those with limited electrical capacity. They can produce a high output, similar to electric models, but may be less energy-efficient and require more maintenance due to their connection to the engine.

Modular vs. All-in-One Systems

Watermakers can also be categorized as modular or all-in-one systems. Modular systems consist of separate components that can be installed in different locations on your boat, allowing for greater flexibility in terms of space and installation. All-in-one systems, on the other hand, have all the components housed in a single unit, making them easier to install but potentially more difficult to fit into tight spaces.

Factors to Consider When Choosing a Watermaker

When selecting a watermaker for your boat, there are several factors to consider, including:

Output Capacity

The output capacity of a watermaker is measured in liters or gallons per hour. To determine the appropriate capacity for your needs, consider your daily water consumption, which may include drinking, cooking, bathing, and washing dishes and clothes. As a general rule, plan for a minimum of 20 liters (5 gallons) per person per day. Keep in mind that it’s better to choose a watermaker with a higher output than you think you’ll need, as this will allow you to run it for shorter periods and conserve energy.

Power Requirements

Consider the power requirements of the watermaker and how it will fit into your boat’s existing electrical system. If you’re relying on solar or wind power, you may need to upgrade your system to accommodate the additional load of an electric watermaker. Alternatively, you could consider a manual or engine-driven model that doesn’t require electricity.

Installation Space

Watermakers can take up a significant amount of space on your boat, so it’s important to consider where you’ll install the system and whether you have enough room. Modular systems offer more flexibility in this regard, as the components can be installed in different locations to maximize space.

Ease of Maintenance

Like any piece of equipment on your boat, watermakers require regular maintenance to ensure they continue to function properly. Some models are easier to maintain than others, so consider the availability of replacement parts, the complexity of the system, and your own comfort level with performing maintenance tasks.


Finally, consider your budget when choosing a watermaker. Prices can range from a few hundred dollars for a basic manual model to several thousand dollars for a high-capacity electric system. Keep in mind that the initial cost of the watermaker is only part of the equation; you’ll also need to factor in the cost of installation, maintenance, and any necessary upgrades to your boat’s electrical system.

Tips for Installation and Maintenance

Once you’ve chosen the right watermaker for your boat, follow these tips to ensure a smooth installation and ongoing maintenance:


  • Carefully read the manufacturer’s instructions and consult with a professional if you’re unsure about any aspect of the installation process.
  • Choose a location for the watermaker that’s easily accessible for maintenance and has adequate ventilation to prevent overheating.
  • Ensure that all components are securely mounted and that hoses and fittings are properly connected to prevent leaks.
  • Install a pre-filter to remove larger particles from the seawater before it enters the watermaker, prolonging the life of the membrane.


  • Regularly inspect the watermaker for signs of wear or damage, and replace any worn or damaged parts as needed.
  • Clean or replace the pre-filter as needed to ensure optimal performance.
  • Periodically flush the system with fresh water to remove any buildup of salt or other impurities.
  • Replace the reverse osmosis membrane as recommended by the manufacturer, typically every 3-5 years or when the output quality begins to decline.


Investing in a watermaker can greatly enhance your sailing experience by providing a reliable source of fresh water on board. By carefully considering your needs and preferences, you can choose the right watermaker for your boat and enjoy the freedom and convenience of having fresh water at your fingertips. With proper installation and maintenance, your watermaker will serve you well for years to come as you explore the open sea with your family.