Water Everywhere

Rainman watermakers are a compact and portable solution designed to generate a fresh water supply from salt or brackish water.
Our system consists of a Pressure Supply Unit (PSU) which pressurises the source water, and a Reverse Osmosis Unit, which desalinates the water with a membrane, removing impurities and creating fresh potable water. The optional Rainman flow guage allows our system to be used in brackish or fresh water applications.

Built to last

We use only top quality components from the best manufacturers: Honda, DOW FILMTEC, General Pump, Jabsco. Our filters, membranes and replacement parts are non-proprietary for ease of service worldwide.


Our system can easily be transferred between boats or used in remote land based locations. You can even use Rainman as a salt water pressure washer with our optional pressure gun attachment.

Petrol or Electric

The Rainman Pressure Supply Unit (PSU) is available with a Honda petrol (gasoline) engine, or multiple electric options. Two AC options operate at either 230V/50Hz or 115V/60Hz, and a lower power 12VDC version

Petrol Pressure Supply Unit

Our original petrol (gasoline) version of the pressure supply unit, perfect for those who want a completely self-contained watermaker without reliance on electricity of any type.

Electric Pressure Supply Unit

AC: 230V/50Hz or 115V/60HZ electric Pressure Supply Unit is optimised to run from a Honda 2kW generator or larger. DC: Our 12VDC system operates at lower power and lower output and is ideal for running from solar / battery power.

Reverse Osmosis

Our Reverse Osmosis systems utilise DOW FILMTEC membranes and couples with a Rainman Pressure Supply Unit.

High Output Reverse Osmosis Case

Two 40" reverse osmosis membranes.

Compact Reverse Osmosis Case

Two 21" reverse osmosis membranes.

Economy Reverse Osmosis Unit

Single 40" reverse osmosis membrane.

The Rainman Advantage

Our simple and robust system is designed for ease of use and low maintenance. This fresh approach to desalination eliminates unnecessary componentry and electronics.
Not only will the initial cost of a Rainman watermaker be lower than other systems, but the simple design and high build quality reduces ongoing maintenance costs.

Flexibility - choose to install your system or run it portable, allowing you to reduce weight while not cruising.
Reliability - using simple pumps and no electronics maximises the uptime of your watermaker.
Lower life cycle cost - not only will the initial price be lower, but ongoing maintenance cost is minimised.
High output - up to 140 litres per hour (37 gph).
Investment retention - keep your watermaker when youchange boats.