Rainman Desalinators



Rainman Desal Units are simple and robust system is designed for ease of use and low maintenance. The fresh approach to desalination eliminates unnecessary componentry and electronics. Not only with the cost of a Rainman Watermaker be lower than other systems, but the design and high build quality reduces ongoing maintenance.

Flexibility – choose to install your system or run it portable, allowing you to reduce weight whilst not cruising.

Reliability – using simple pumps and no electronics maximises the uptime of your watermaker.

Economical – modest initial price and low maintenance requirement minimises life cycle cost.

High output – Up to 140 litres per hour

Investment Retention – If going for the portable unit you can keep it when you change boats and also use for camping and caravaning


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 pressurizes the source water, and a Reverse Osmosis Unit, which desalinates the water with a membrane, removing impurities and creating fresh potable water. The PSU comes in 240v, 12VDC or Petrol option and can be paired with single 21″ membranes up to twin 40″ membranes.

The optional Rainman flow gauge allows our system to be used in brackish or fresh water applications.


Although the Rainman watermaker was originally designed as a portable system not requiring installation, many of our customers choose to partially or fully install the system in their boat. The variations can range widely, including the installation of both the pressure supply unit and reverse osmosis case to installing one or the other of the units.

If you want to permanently install your system, do not require future portability, and want a minimum footprint installation, the Rainman Naked watermaker is a good option.  Any of the electric pressure supply units can come in the Naked configuration.

This system has the same internals and performance as the traditional Rainman system, with an integrated lift pump so there is only one motor to switch on.

The Rainman Naked system excludes the blue shells, and includes a variety of valves and hardware useful for your installation.

Three main components (pump/motor, prefilter, RO unit) can be mounted separately from each other.  The valve/gauge controls are to be mounted remotely, so the watermaker can remain out of sight.

Installation Guide


Using 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, for caravanning, camping and fishing trips. You can even use Rainman as a salt water pressure washer with our optional pressure gun attachment.

PSU Type / RO Unit High Output Compact Economy
AC Electric 1250 watts AU$ 7,504
100-140lph (26-37gph)
AU$ 7,073
50-70lph (13-18gph)
AU$ 6,134
50-70lph (13-18gph)
Petrol (Gas) 1 hr, 700ml, 0.18gl AU$ 8,958
100-140lph (26-37gph)
AU$ 8,527
50-70lph (13-18gph)
AU$ 7,588
50-70lph (13-18gph)
12VDC 32 amps Not
AU$ 6,789
26-34lph (7-9gph)
Accessories and Spares Price
Rainman Autoflush Kit AU$474
Pre-Filter Cartridge (5 micron) AU$11
HM Digital COM80 Hydrotester AU$58
Impeller Replacement AU$53
Brackish Water Flow Gauge AU$466
Pickle Solution Mix – 1kg (2.2lb) AU$40
40″ RO Membrane (Filmtec) AU$443
21″ RO Membrane (Filmtec) AU$428
5 metre high pressure hose AU$111