A Boat Watermaker's Working: All You Need To Know

Marine watermakers are devices that convert seawater into safe, fresh drinking water. They are used by seafarers to ensure a constant supply of potable water while at sea. Watermakers are also referred to as desalinators and are particularly useful for long-distance ocean cruisers. They can be expensive to acquire and maintain, but they reduce the need for large water tanks.

Watermakers use reverse osmosis to convert seawater into drinking water

The heart of any marine watermaker is a process called reverse osmosis. Reverse osmosis is the principle where we reverse natural osmotic pressure to separate the saline content from seawater, thereby producing fresh and drinkable water. Popular brands of yacht watermakers typically make from 2 to 150 litres per hour of operation (0.53 to 41 gallons) depending on the model. There are strong opinions among small boat cruisers about the usefulness of these devices. The arguments may be summarised as: A watermaker uses only a small amount of fuel to generate a large amount of water, eliminating the need for large, heavy water tanks. The user is independent of shore-based water supplies, which is especially important in remote areas. They provide safe water when shore-based water is of uncertain quality. Some designs are portable and can be converted to manual operation in an emergency.

Most cruising boats are likely to fit a powered device that does the hard work for you and produces enough for all the boat’s fresh water needs. Broadly speaking, these fall into two main categories: those that produce the necessary pressure by using a traditional high-pressure pump, and those that use a dual piston Clark pump known as an energy recovery device (ERD).

Watermakers are expensive to acquire and maintain

The process of reverse osmosis involves a high-pressure pump forcing seawater through a membrane that allows water but not salt to pass through. This can be achieved through a traditional high-pressure pump or a dual piston Clark pump, known as an energy recovery device (ERD). Depending on the design, watermakers can be powered by electricity from the battery bank, an engine, an AC generator or hand-operated.

Watermakers designed for small boats and yachts rely on the same technology, and popular brands typically make 2 to 150 litres per hour of operation. Some argue that watermakers are useful as they use only a small amount of fuel to generate a large amount of water, and they provide safe water when shore-based water is of uncertain quality. However, there are strong opinions among small boat cruisers about the usefulness of these devices. Some designs are portable and can be converted to manual operation in an emergency.

Watermakers are portable and can be converted to manual operation in an emergency

Watermakers are devices that use reverse osmosis to obtain potable water from seawater. They are often referred to as "desalinators", and can be expensive to acquire and maintain. However, they are valuable because they reduce the need for large water tanks on long passages. Watermakers can be powered by electricity from a battery bank, an engine, an AC generator, or hand operation.

Some watermaker designs are portable and can be converted to manual operation in an emergency. These devices are typically handheld and manually powered. To use them, you immerse the inlet filter into a bucket of seawater and pump by hand to produce safe drinking water. This type of watermaker is often found in offshore liferaft kits and can provide enough water to keep someone alive.

Watermakers can be powered by electricity, an engine, an AC generator or hand operation

Watermakers are devices used to obtain potable water by reverse osmosis of seawater. In boating and yachting circles, they are often referred to as 'desalinators'. They can be expensive to acquire and maintain, but they are valuable because they reduce the need for large water tanks for long passages.

Most cruising boats, however, are likely to fit a powered device that does the hard work for you and produces enough for all the boat’s fresh water needs. These fall into two main categories: those that produce the necessary pressure by using a traditional high-pressure pump, and those that use a dual-piston Clark pump known as an energy recovery device (ERD).

Watermakers are used by long-distance ocean cruisers

Watermakers use the principle of reverse osmosis to separate the saline content from seawater, producing fresh and drinkable water. This process involves using a high-pressure pump to force seawater through a membrane that allows water but not salt to pass through.

The amount of water produced by a watermaker depends on the model, with popular brands typically making between 2 and 150 litres per hour of operation. Watermakers can be powered by electricity from the battery bank, an engine, an AC generator, or hand operation. Some designs are portable and can be converted to manual operation in an emergency.

Watermakers can be expensive to acquire and maintain, but they are valuable for long-distance ocean cruisers as they provide a constant supply of potable water and eliminate the need for shore-based water supplies, which may be of uncertain quality or unavailable in remote areas.

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