If you don’t find the answer to your question, feel free to contact us.
Can I use this system in Brackish and Fresh Water?

The Rainman Desalination Systems were designed for turning seawater into pure, fresh drinking water. However, it will also turn brackish or contaminated fresh water into fresh, pure drinking water, in minutes.

Turning brackish or fresh water into pure drinking water is much easier than converting saltwater. It does not require the same 800 PSI to accomplish. You simply need to dial back (regulate) the pressure so as not to over whelm the capacity of the R.O. membranes. This can be avoided by keeping the pressure needle in the Green spectrum on the pressure dial and not allowing it to roam into the RED spectrum.

Installing the optional “brackage water flow gauge” will help you determine the maximum allowable output for your R.O. filter system, quickly and easily.

Can I drink the water?

YES! The Rainman Desalination System was designed exactly for that purpose. This system will produce water that is 99.9% pure water.

How long will the membranes last?

The life expectancy of the R.O. filters will be determined by a host of variables such as:

The quality of the water being run thru the filters. If you are making water in an area that has a lot of petroleum products (gas or oil), you will shorten the life of your filters.

The care and maintenance of the filters. If the filters are “Flushed” with fresh water and pickled when not being used, you will receive the maximum life expectancy.

The total run time or number if gallons produced will of course effect the life expectancy.

If reasonable care and maintenance is followed, the average boating user can expect between 6-8 years of productive life of the membranes.

Can I run this unit with my generator?

It depends! The Rainman Electric 115V 60Hz unit requires the use of a Honda 2KW generator (or bigger). The Honda generator produces the initial surge required to start the motor. Some other name brands of 2KW generators may or may not have the initial power required. Any brand generators larger than a 2KW will work just fine.

How easy are in-field repairs if they become necessary?

Our objective is to keep the system non-proprietary, so we used common industry parts and fittings for the system design wherever possible. All the key components are readily available from within the pressure supply unit using typical spanners (wrenches) and other tools one would expect to be in a common tool bag. Although we recommend servicing by qualified technicians, owners with mechanical aptitude should not have a problem maintaining the unit.

How easy is the system to operate?

Very simple. You bring the pressure supply unit and RO membrane case on deck and attach the high pressure hose between them. Put the take-up and brine discharge hoses in to the sea and the fresh product water hose in to your tank. Start the electric or petrol motor and close the valve on the RO unit until pressure hits about 55 bar (800 psi). You will now be making fresh water. See the quick reference card or operations manual for more complete details (example documents for petrol/gasoline version).

How long will a Rainman system last?

With proper care and maintenance, a Rainman desalination system is designed to last over ten years for average pleasure craft use. Usage and maintenance patterns will obviously affect longevity.

Is installation necessary?

The beauty of this system is that no installation process is required. You can choose to install it if you wish, or keep it as a portable appliance. More information on the pros and cons of installation.

Many watermakers have two pre-filters, why does Rainman only have one?

Many watermakers have a 20 micron followed by a 5 micron pre-filter. They are typically installed below deck and in difficult to reach areas, so changing filters is a cumbersome and messy task. Rainman is often run on deck and is more easily inspected and accessed. This makes changing filters very easy, so we decided to keep the system more portable and go with a single 5 micron pre-filter. We can make custom modification to include dual pre-filters upon request.

What about an energy recovery pump to make operation more efficient?

Several very creative designs exist for energy recovery pumps. However, we feel they are unnecessarily complex and expensive for the gains they provide. Greater complexity often means more maintenance and chance of failure in the future. We chose to use top quality materials in a design that is as simple as possible, eliminating complex valve systems and O-rings where we could. We have also found that as the cost of power comes down (generators, solar, batteries, etc.), people are shifting their preference towards high reliability and simplicity.

What are the advantages of Rainman over other types of watermakers?

While there are many quality manufacturers of desalination equipment on the market today, a Rainman desalinator offers a unique solution. Advantages include:

  • Portability – you can reduce weight of your boat while not cruising and also keep your investment if you change boats
  • Simplicity – our minimalist design means fewer complex parts to require maintenance or fail
  • Less expensive – our system costs less to buy and maintain than other watermakers, so the total life cycle cost is reduced
  • High output – depending on chosen configuration and operating conditions, our system can provide up to 140 litres per hour
What care is required for my Rainman system?

Apart from pickling the RO membrane when necessary and changing the pre-filter when dirty, we recommend changing the oil in the pump and motor after the first 10 hours of use and every 50 hours of use thereafter.

What consumables should I keep on hand for the system?

With proper care, your Rainman desalination system will last for years. It is advisable to keep spare pre-filter cartridges and pickling concentrate on hand. The Jabsco lift pump has a rubber impeller blade that will require changing every few years, depending on use. While the belt is designed to last for years, some people will have a preference to keep a spare for extended cruising. See our consumables & spares page for more details. Obviously the petrol pressure supply unit will require fuel as well.

What does “pickling” the membrane mean, and how is it performed?

“Pickling” the membranes is a necessary process used to protect your RO membranes when unused for a period of time. Rainman is the simplest system on the market to pickle because the pickup hose can be placed in a bucket of pickle solution. In built systems require a complex three way valve system. See our owners manual for details on how to perform the pickling.

What is the sound level of the system while it’s running?

The petrol (gasoline) system is slightly queieter than a Honda 2kVA generator running at maximum load. Our AC systems make a loud hum, while our 12VDC systems make a quiet hum.

What is the warranty of my system?

Rainman desalinators come with a two year return to base warranty against manufacturing defect. The Honda motor in the petrol pressure supply unit is covered by a three year Honda warranty. As we are a Honda OEM, you can bring your Honda motor in for service to any Honda dealer globally.

What storage requirements exist for the system?

The pressure supply unit should be stored as near to upright as possible to keep the engine properly oriented. The RO membrane case can be stored in any orientation, but the temperature should be between 5°C (40°F) and 35°C (95°F). Note that if the membranes are not pickled, cooler temperatures will allow longer storage before bacteria begins growing. Do not allow the membranes to freeze.

Why are there fewer valves and gauges than other systems I’ve seen?

Rainman Desalination set out designing the system to be as simple as possible, without unnecessary bells and whistles. While many measurements may be somewhat interesting, the only necessary gauge is pressure at the RO membrane and the only necessary valves are one for controlling that pressure and another relief valve for safety.

Why is there an air bubble in my pressure gauge?

Liquid filled gauges are the highest quality and most durable ones available. The air bubble is part of design, and exists to allow the glycerine fluid to expand and contract as the temperature fluctuates. The purpose of the glycerine fluid is to dampen needle movement.