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Frequently Asked Questions - Sales

Why do I have to fresh water flush my watermaker?
Seawater contains two things that can shorten the life of any RO membrane; minerals and living organisms. If seawater is allowed to remain in contact with the membrane, minerals will begin to adhere to the surface; a fresh water flush will actually dissolve many minerals and stops this from happening. Seawater is also full of microscopic life and as the oxygen is consumed when the system stops, these organisms begin to die and decay. This decay causes bio-fouling which smells bad and will also lead to low-oxygen corrosion that will attack the stainless steel components critical to the function of any watermaker. Fresh water flushing virtually eliminates all these problems.
How does Reverse Osmosis work?
Reverse Osmosis is a filtration process that will separate individual water molecules from an undrinkable feed water source like seawater. In the case of seawater desalination high pressure is required (600+psi) to force individual water molecules through the Reverse Osmosis (RO) membrane while flushing salts, minerals, viruses, bacteria or any other contaminant down the drain. Using seawater or contaminated brackish feed sources, a properly designed RO system can provide pure, safe and great tasting water.
What makes Spectra different?
Spectra has spent years developing our patented high pressure intensifier pump technology with integrated energy recovery that allows us to create the high pressure required for RO based desalination, 600 - 1000psi (45 - 69Bar), using a low pressure, 60 - 200psi (4 - 13.8Bar) pump that will operate off your boat's 12 volt battery. Our unique technology allows us to produce pure water using less than half the energy required by standard RO systems, which means our systems can work off standard 12v DC solar or wind driven power systems. After 30 years in the Marine Industry we understand the onboard environment, so we engineer our equipment be robust, efficient and reliable and we offer unmatched after-sales support.
What is “energy recovery”?
Traditional methods of Reverse Osmosis Desalination require power hungry pumps, high pressure valves, and brute force to generate the pressures required to make pure water. The high pressure waste stream in a traditional system goes down the drain so all the potential energy is lost. “Energy Recovery” refers to a method by which our systems can capture and re-use the high pressure waste stream before it goes down the drain thereby significantly reducing the load on your ship's batteries and/or generator. In most situations Spectra's proprietary technology allows us to operate on less than half of the energy required by these traditional systems, the end result being that you get more water for less energy.
What does the MPC 5000 do?
It's a completely automated control system designed specifically to manage the operation of a Spectra Watermaker. It monitors the condition of the filters, automatically diverts the product water to your tank when the water quality is acceptable, fresh water flushes itself after running, and shuts itself down if anything bad happens - like sucking a jellyfish into the sea-strainer. The MPC 5000 will also automatically fresh water flush your system at a predetermined, and adjustable, interval when it is not in use, making your life easier, protecting the membrane and your investment at the same time. When connected to tank switches the system will operate automatically, turning itself on and off as the tank level demands, and then flushing itself in between run cycles. This is true industrial level automation.
Can I use solar panels to power my watermaker?
Spectra Watermakers were built to run on solar power! Our watermakers are designed to run on 12v batteries, without the generator running. We build a full line of DC watermakers ranging from 6.5 to 420 gallons per hour (24.6 to 1590 liters per hour) of fresh, potable water. All equipment is designed to avoid high start-up loads with soft start technology, energy recovery to reduce the operating power required, and automated controls to make operation as efficient and as simple as pushing a button.
Can I run a Spectra Watermaker on my inverter?
Yes you can! In certain situations it is advantageous to use an AC watermaker. Our AC powered systems are built using a soft-start motor speed controller so the starting loads are very low; this means that most inverters are more than capable of starting and operating your AC watermaker without ever turning on the generator. Our Technical support desk can fill you in on the details.
What is the Z-Brane, and does it really work?
The Z-Brane uses electrostatic charge technology to reduce or completely eliminate the need for chemicals for cleaning or storage of your watermaker. By placing a positive charge on all the molecules in the membrane everything stays in suspension and will not accumulate on the membrane surface (kind of like two magnets will repel each other). The Z-Brane is a simple solution to system maintenance.
How long does a membrane last?
The life a membrane is directly dependent on how well it is cared for, which is why our many of our systems include automatic fresh water flushing. Keeping the membrane clean and stored in fresh water during voyages can add years to the service life of any membrane. Proper long term storage, or pickling, is also important for longevity. A well maintained reverse osmosis membrane can easily last 5 to 6 years, we have some customers with 10 year old membranes.
How much water do I need?
The simple answer is “more than you think”. In reality, it depends on how many people are going to be on the boat, where you plan to go and for how long, and what the weather's going to be like. Most of our customers find that the ease of use, the quietness, and the convenience of our systems gives them the security to drink more water, take more showers, wash their decks down with fresh water instead of salt; all in all, they consume a lot more water than they ever dreamed they would have. The most common mistake when purchasing a watermaker is to underestimate your needs so our best advice is to be realistic with how much water you will use, and when in doubt buy a larger capacity system.
What is the Clark Pump?
The Clark Pump is one of our patented technologies, and is not actually a pump, but a pressure amplifier. The beauty of the Clark Pump is in the simplicity of its design; by recycling the high pressure brine waste stream to help pressurize the seawater coming into the system, this allows our systems to use a low pressure feed pump in order to generate the 600 -1000psi (45 - 69Bar) required inside the membrane to make pure water. Even better, the watermaker runs off the battery (no generator!) and is almost silent so you can enjoy a quiet evening in the cockpit without ever hearing your watermaker.
What is the Pearson Pump?
The Pearson Pump is another of our patented technologies designed for higher output systems and just like the Clark Pump, recycling the high pressure brine waste stream back to the pump to help pressurize the seawater feeding the membrane substantially reducing the energy required to make water. The Pearson Pump technology was developed to meet the demands of the land based solar powered desalination markets, larger yachts, and those customers that need the ultimate in energy efficiency and water production. The pumps are constructed of super duplex stainless steel and corrosion proof composites for a lifetime of trouble free performance. With pumps ranging from 75 Gallons per Hour (284Liters per Hour) up to 420 Gallons per Hour (1590 Liters per Hour), the Pearson Pump delivers high volume reverse osmosis desalination with industry leading energy conservation technology.
I've heard the Clark Pump cycling can harm a membrane, is this true?

We started selling systems in 1998, and as many of our early customers are still using the original membrane installed (13 years later!), it is safe to say that this myth is unfounded! There is no evidence that suggests that either the Clark Pump or Pearson Pump have any negative impact on the longevity of the membrane or the permeate quality. Some lab tests have indicated that pulses in the feed water stream can actually help extend the life of the membrane.

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