Installing a watermaker on your boat
Installing a watermaker on your boat

Having a reliable source of fresh water is essential for long-term sailing trips. Learn about the different types of watermakers and how to install one on your boat to ensure a continuous supply of fresh water while exploring remote locations.

Installing a Watermaker on Your Boat

As you embark on your sailing adventure with your family, one of the most important aspects to consider is having a reliable source of fresh water. While you can carry a certain amount of water on board, it’s not always feasible to store enough for long voyages. This is where a watermaker comes into play. In this article, we will discuss the importance of watermakers, the different types available, and how to install one on your boat.

Why You Need a Watermaker

A watermaker is a device that converts seawater into fresh, potable water through a process called desalination. This is essential for long-term sailing trips, as it allows you to have a continuous supply of fresh water without having to rely on shore-based sources. Some of the key benefits of having a watermaker on your boat include:

  • Self-sufficiency: With a watermaker, you can produce your own fresh water, reducing your dependence on marinas and other shore-based water sources. This gives you the freedom to explore remote locations and stay at sea for extended periods.

  • Safety: In case of an emergency, having a watermaker on board can be a lifesaver. If your water supply becomes contaminated or runs out, a watermaker can provide you with the fresh water you need to survive.

  • Convenience: A watermaker allows you to produce fresh water on demand, eliminating the need to ration your water supply or make frequent stops to refill your tanks.

  • Cost savings: While the initial investment in a watermaker can be significant, the long-term savings can be substantial. By producing your own water, you can avoid the high costs of purchasing water at marinas and other shore-based sources.

Types of Watermakers

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

Reverse Osmosis (RO) Watermakers

Reverse osmosis is the most popular and widely used method of desalination. RO watermakers work by forcing seawater through a semi-permeable membrane, which filters out the salt and other impurities. The result is fresh, potable water.


  • Highly effective at removing salt and other impurities
  • Produces high-quality, great-tasting water
  • Available in a wide range of sizes and capacities


  • Requires a significant amount of energy to operate
  • Can be expensive to purchase and maintain
  • Produces a large amount of brine (waste water) that must be disposed of

Distillation Watermakers

Distillation watermakers work by heating seawater to create steam, which is then condensed back into fresh water. This process effectively removes salt and other impurities.


  • Effective at removing salt and other impurities
  • Can operate using waste heat from your boat’s engine, reducing energy consumption


  • Produces lower-quality water compared to RO systems
  • Can be slow and inefficient, especially in cooler climates
  • Requires regular cleaning and maintenance to prevent scaling and corrosion

Electrolysis Watermakers

Electrolysis watermakers use an electric current to separate the salt and other impurities from seawater. This process is less common than RO and distillation, but it can be an effective option for some boaters.


  • Low energy consumption compared to RO systems
  • Produces high-quality water


  • Less effective at removing impurities compared to RO and distillation systems
  • Can be expensive to purchase and maintain
  • Requires a reliable source of electricity to operate

Choosing the Right Watermaker for Your Boat

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

  1. Capacity: Determine how much fresh water you will need on a daily basis. This will depend on the size of your crew, your water usage habits, and the length of your voyages. Choose a watermaker with a capacity that meets or exceeds your daily water needs.

  2. Energy consumption: Consider the amount of energy your watermaker will require to operate. If you have limited power resources on your boat, you may need to choose a more energy-efficient option, such as a distillation or electrolysis system.

  3. Space and weight: Watermakers can be bulky and heavy, so make sure you have enough space on your boat to accommodate the system. Keep in mind that larger-capacity watermakers will generally be larger and heavier than smaller-capacity models.

  4. Budget: Watermakers can range in price from a few thousand dollars to tens of thousands of dollars. Determine your budget and choose a system that fits within your price range.

  5. Maintenance: All watermakers require regular maintenance to ensure optimal performance and longevity. Consider the maintenance requirements of each system and choose one that you feel comfortable maintaining.

Installing a Watermaker on Your Boat

Once you have selected the right watermaker for your needs, it’s time to install it on your boat. While the installation process will vary depending on the type and model of watermaker you choose, here are some general steps to follow:

  1. Choose a location: Find a suitable location on your boat to install the watermaker. This should be a well-ventilated area with easy access for maintenance. Make sure there is enough space to accommodate the system and any additional components, such as pumps and filters.

  2. Install the components: Follow the manufacturer’s instructions to install the various components of your watermaker, including the membrane housing, pumps, filters, and control panel. Be sure to secure all components properly to prevent damage from vibration and movement while underway.

  3. Connect the plumbing: Connect the watermaker to your boat’s existing plumbing system, including the seawater intake, fresh water output, and waste water discharge. Be sure to use high-quality hoses and fittings to prevent leaks and ensure a reliable connection.

  4. Connect the electrical system: Wire the watermaker to your boat’s electrical system, following the manufacturer’s instructions for proper voltage and amperage requirements. Be sure to use marine-grade wiring and components to ensure a safe and reliable connection.

  5. Test the system: Once everything is installed and connected, test the watermaker to ensure it is operating properly. Check for leaks, monitor the system’s performance, and make any necessary adjustments to ensure optimal performance.

  6. Perform regular maintenance: To keep your watermaker running smoothly and efficiently, be sure to perform regular maintenance as recommended by the manufacturer. This may include changing filters, cleaning the membrane, and inspecting the system for wear and damage.


Installing a watermaker on your boat is an essential step in ensuring a reliable source of fresh water for your sailing adventures. By understanding the different types of watermakers available, choosing the right system for your needs, and following the proper installation and maintenance procedures, you can enjoy the freedom and self-sufficiency that comes with producing your own fresh water at sea.