Interview with the watermaker. The secrets of an increasingly popular onboard accessory


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HP Watermakers - SCA 100 Kilo
HP Watermakers – SCA 100 Kilo

The watermaker is the accessory of the moment. More and more boat owners want it on board their boats, partly because it is now so common to use the boat not only for day trips, and partly because there is more and more space on board. For on the one hand, boats are getting larger and larger, and on the other hand, many prefer outboard motorization even where inboard would be planned, freeing up space-for example, for the watermaker. We find out with Gianni Zucco, co-founder of the Italian watermaker HP Watermakers, the secrets of this accessory through 7 questions.

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1) Why is a watermaker on board important?

2) How does the reverse osmosis desalination process work?

3) How has the technology of onboard desalinators evolved?

4) Why are HP Watermakers’ desalinators really automatic?

5) What is the difference between desalinator and water softener? Is the water produced drinkable?

6) Is it possible to install a watermaker on an already sailing boat and from what size?

7) How can I evaluate with a competent technician the possibility of installing a watermaker?


Gianni Zucco - co-founder of HP Watermakers
Gianni Zucco – co-founder of HP Watermakers

1) Why is a watermaker on board important?

If you want to have the total onboard experience, without having the anxiety of water tanks emptying, without having to be careful not to overdo the showers…in short, to experience the sea in comfort without the stress of having to dock to replenish your water supply, the watermaker has become, with the power generator, an essential accessory. It is no coincidence that HP Watermakers has forged a partnership with Mase and GenSet, leading manufacturers of power generators and gensets respectively, to which we have given the name ‘Together We Boat’: a strategic alliance based on common vocations for cutting-edge technology, business dynamism and improving the quality of life on board.

2) How does the reverse osmosis desalination process work?

It should be pointed out immediately that reverse osmosis technology is practically the only one adopted in recreational boating. On large ships, and thus on megayachts as well, evaporation of engine cooling water is also used to make distilled water that is then mineralized, but it is an expensive and uncompetitive technology for the vast majority of pleasure boats, which is normally used on commercial vessels. The principle of reverse osmosis, on the other hand, is very simple: you draw water from the sea, compress it inside osmotic membranes that separate salt water from fresh water. This is the finest water filtration technique, The membranes used in reverse osmosis are generally made of polyamide, a substance chosen primarily for its water permeability and relative impermeability to various dissolved impurities, including salt ions and other small molecules that cannot be filtered out.

3) How has the technology of onboard desalinators evolved?

The first reverse osmosis desalinators are over forty years old. For many years the technique of their construction has undoubtedly been refined, but no substantial progress has been made in simplifying their use. From the above description, it is quite intuitive that a manual desalinator requires continuous work on both pump pressure (depending on salinity and seawater temperature, which, as you can well imagine, are constantly changing during navigation) and membrane maintenance (flushing). These are the two operations that the vast majority of desalinators (about 80 percent) still require to be done manually, so with a minimum of skill, but most importantly, care. Then there are semiautomatic models where membrane washing is automated at each end of the production cycle, but human intervention is still required because the pressure regulating valve remains, installed at the end of the circuit if not manually opened, does not allow the washing water to flow out and thus the salts remain inside the membranes, crystallizing over time. Finally, there are the fully automatic desalinators where both operations are done automatically without the need for intervention by the sailor or shipowner. HP Watermakers was the first to develop automatic watermakers 20 years ago, while also remaining present in the non-automatic model segment.

4) Why are HP Watermakers’ desalinators really automatic?

HP Watermakers' BiBi system integration.
HP Watermakers’ BiBi system integration.

The term automatic is often misused, and desalinators are certainly no exception. In HP Watermakers, when we talk about automatic we mean a real ‘appliance’ that can be operated with a few simple commands, just like an air conditioning system. To do this, we developed the patented RP TRONIC system, which is the watershed between manual and automatic desalinators because it made it possible to automate the regulation of seawater pressure on osmotic membranes. In practice, the high-pressure pump sends seawater to the membranes, and the RP TRONIC valve downstream of them ensures that the pressure is kept constant at 60 bar; if this does not happen, freshwater production suffers. Especially when sailing, with a manual valve it would require constant checking by having to go down to the engine room each time. In fact, in the case of increased salinity, production would inevitably decrease and pressure would increase to the point of shutting down the plant due to too high a pressure, while at an increase in temperature the opposite phenomenon would occur, i.e., pressure would drop, as would plant productivity. It is therefore understandable how much the two elements interact with each other and can affect the smooth operation of the desalinator. HP Watermakers is the only manufacturer to have developed and patented an automatic system to ensure continuous pressure regulation consisting precisely of the RP TRONIC valve as early as 20 years ago. A similar argument can be made for the automatic flushing of the membranes, which is standard on HP Watermakers desalinators: RP TRONIC, which like all pressure control valves is located at the end of the circuit as if it were a closed faucet, opens automatically, allowing all the salt water to drain out of the system but especially out of the membranes. This is also important because, if not rinsed properly, the salt deposited on the membranes will crystallize in the long run, requiring chemical flushing to restore them to full efficiency, an eventuality that is the norm with a manual valve. But HP Watermakers’ attention to the durability and efficiency over time of its desalinators goes even further: in fact, thanks to the AMCS (Automatic Membrane ConservingSystem), another HP Watermakers exclusive, during each shutdown and flushing cycle a dispenser injects a few drops of sodium metabisulfite onto the membranes, an inert compound that is harmless to the membranes, but essential to prevent bacterial growth and thus the creation of mucilage, which is always possible considering the absence of chlorine. With all these systems, the lifetime of the membranes can be up to 10 years.

5) What is the difference between desalinator and water softener? Is the water produced drinkable?

To simplify, the desalinator separates transforms salt water into fresh water, starting with seawater while the softener sequesters calcium molecules from ‘water, preventing the formation of the scale molecule; and in boating it can be used to treat dock water. As for the potability of the water produced by a desalinator, it is not certified because a declaration from a third party would be needed, and it is unthinkable in the sea, where conditions are constantly changing; it is certainly purified water and therefore drinkable although it must be remembered that it is stored in tanks in which it is necessary to activate protection from the bacteria that inevitably form. It is therefore advisable to have a second pass before drinking it, and in this regard HP Watermakers has developed the GENIUS system, the water dispenser that is connected directly to the on-board drinking water supply and produces fresh and/or sparkling water for food use, using ultrafiltration membranes and silver ions. In addition, installing a UV sterilization system at the tank outlet can protect all freshwater distribution lines on board.

6) Is it possible to install a watermaker on an already sailing boat and from what size?

HP Watermakers' Water Package on board a yacht
HP Watermakers’ Water Package on board a yacht

Anything is possible: many new boats leave the yard without a watermaker, the installation of which is usually left to the dealer before delivery or after the first season when the owner realizes that the watermaker has now become indispensable. On an older boat, the space in the engine room should be checked and, if necessary, a sea socket should be applied. We have made installations on boats with a rather cramped engine room, ‘hanging’ the watermaker from the canopy with brackets almost above the engines. As for the size of the boat, consider that our smallest model HP SCA100 KILO, designed specifically for small- to medium-sized boats, is capable of producing 100 l/h with a consumption of 1 kW and weighs only 60 kg; therefore, it can also be installed without particular problems on a dinghy or daycruiser. All our models are ready for full automation thanks to RP TRONIC compatibility; if anything, to be checked is the compatibility with on-board systems and thus the possibility of being able to take advantage of our Part- NET interface, which is fully compatible with on-board electronic systems from brands such as Raymarine, Garmin, Furuno, Simrad, B&G and Lowrance. Part-NET allows the user to control the entire desalination system-including pressure and all other operating parameters-from the in-dash plotter, or even from smartphones when an Internet connection is available, without any manual intervention.

7) How can I evaluate with a competent technician the possibility of installing a watermaker?

To check the feasibility of an installation aboard one’s boat, it is undoubtedly necessary to contact qualified personnel. That is why in HP Watermakers we have paid special attention to the development of our worldwide network. From Dubai, the point of reference for the Middle Eastern market, to Fort Lauderdale, Florida, a key garrison for the United States, Canada, Mexico and the Caribbean, not forgetting the Maldives and South Africa, joined by 56 other dealers operating in as many countries around the world. In Italy, our network makes use of about 80 (number) dealers distributed throughout the country. At each of these locations, boat owners will be able to find technical staff ready to recommend the best solution for their boat, take care of the installation, and, of course, ensure timely after-sales service. On the peace of mind of technical support, another of our exlcusive systems also contributes: it is called BiBi and is the world’s first and only Internet interface for automatic desalinators. BiBi can be optionally installed on both new and aftermarket systems, and thus technical support on the desalinator is implemented remotely, notifying the type and extent of any malfunction in advance and communicating directly with the user through real-time notifications. BiBi also communicates with HP’s operations center to assist the user in an alarm or emergency situation and can send an alarm report to the authorized HP service nearest the user. The system connects the desalinator to the Internet and works through a cloud application on which users can log in via a dedicated password, so they will have access to desalinator control and full diagnostics. It will then be possible to turn the machine on or off, reset alarms, monitor its operation, and have all the data of its operation via any device with an Internet connection. Finally, with BiBi it adds one year to the watermaker warranty, so for a total of four years with priority service.



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