The Importance of a High Output Water Maker Boost Pump

A common question I get by email is about the boost pump.  Do I need one?  What does it do?  Why is yours standard with the water maker and others offer it as an option? What if I mount everything below the water line, do I need one then?  The question are common enough that I thought a video addressing the issue would be useful.  So on a rainy December day while on the Morro Bay, CA mooring ball I pulled out my video camera and started talking about the topic.

Seven Seas Cruising Association Melbourne, FL GAM

While at the Seven Seas Cruising Association in Melbourne, Florida I had the privilege of meeting Sherry, who was picking up here 20 gallon per hour water maker to install it herself!



Where Can I Run my Cruising Water Maker?

The short answer is if you you would swim in the water, then you can run your water maker there.

For a little more details, I put together this YouTube video on where you can and shouldn’t run your cruising boat water maker.


Sailboat Watermaker Installation on a Crealock 37

Small Sailboat Watermaker Installation

Hi Righ, here are several photos showing the installation of your water maker on Lagniappe, our Crealock 37.   I was concerned with where I could mount the various components but everything other than the control panel fit nicely in the engine room on the port and starboard bulkheads.

 System works great and served us well last season in the Bahamas. 

 Thanks for your support and guidance during the installation and commissioning. 


 Greg & LizAnn Mulvany

S/V Lagniappe

Crealock 37


Here are some photos of Greg’s installation. First I have to compliment Greg on having such a darn clean and nicely laid out aft engine compartment.  I’m sure it was fun to hold the motor up on the bulkhead for mounting, but what a great job of using “wasted space” to mount gear.  The installation highlights that you can mount the motor on a vertical bulkhead by rotating the pump on the motor 90-degs.

watermaker high pressure pump


From thhis angle you can really see how every inch of space was used for the water maker.

Watermaker on a small sailboat


Greg mounted the remote panel in the lazarette and this photo shows his 1/4″ red sample hose that is used to test the product water quality before sending the water to the tank.  If you look closely, you can see the white float in the flowmeter and the PSI pressure gauge is set to 800psi, so the unit is running.

water maker lazarette panel location


It may seem obvious when you see it, but I like this photo because it shows Greg using his product water sample line to easily refill his on-deck water jugs.   Our Hudson Force 50 carries 450 gallons of water, but we still keep a 5 gallon water jug on deck for emergencies or to share with our friends that don’t have a watermaker!

Marine watermaker filling a sailboat water jug





Tartan 37 Water Maker Installation

When I heard one of our water maker clients was making a stop over in Morro Bay, of course we had to have some cockpit drinks with them and snap a few photos of their SeaMaker 30 water maker installation.  I have to admit that Lewis on SV Eleutheria did an installation job that puts some professional boat yard installations to shame.  The happy crew is on their way to Mexico and their great use of space on their 37ft boat allowed them to install a 30 gallon per hour water maker without giving up much storage space.  They will be powering their water maker using the trusty Honda UE2000i generator and at $900 with free shipping over the internet  for the Honda, I wouldn’t want to go cruising without one!

Here’s a shot of the beautiful cruise ready boat on a Morro Bay mooring ball.


Where do put the control panel?  How about making use of some wasted space behind the campanion way ladder?

Small boat watermaker installation Tartan 37


The 5 and 20 micron prefilters and Valving and Cleaning assembly are both mounted on the starboard cockpit locker forward bulkhead.

Sailboat watermaker prefilters mounting location



The High Pressure pump and motor are mounted on a shelf in the starboard cockpit locker and you can see the RO Pressure Vessels mounted up high in the cockpit coaming.

Sailboat watermaker high pressure pump mounting location

A favorite mounting location of mine for the RO Pressure Vessels is tucked up in the cockpit coaming.  It’s typically wasted space so you don’t lose valuable storage space.  Notice how nicely Keith tabbed the fiberglass mounting feet of the pressure vessels right to the hull.  Nice and clean installation.

Sailboat water maker pressure vessels




Water Maker Installation and a Dedicated Through Hull

A common question about water maker installations is if you need a dedicated through hull.







A 12v to 120v Water Maker Swap Out

Mark on SV Reach has been out cruising for a few years with a 12v DC 8GPH water maker and decided it was time to upgrade to a higher output water maker.  So after shopping around, he bought our 30 gallon SM30 water maker.  As many cruisers with 12v DC low output water makers find out, you just can’t have enough water while out cruising.  You can check out his installation photos on his blog at SV Reach Blog Click Here.

Water Maker Installation: 1997 Hunter 40.5

SV Gypsy Wind a 1997 Hunter 40.5 all ready to head South to Mexico and Beyond on the 2013 Baja Ha-Ha Cruisers Rally

The bulk of the water maker is installed in a hanging locker.  High Pressure Pump, prefilters, and the valving and cleaning assembly.  To save space, the two 3-way valves were removed from the Activated Carbon filter and mounted remotely.  A nice easy idea.


Remote panel mounted outside the locker.  Most of our panels come with switches for the Hp and Boost pumps, so this panel is not standard.


Due to space limitations, the client could not use our standard 40″ (SW30-2540) RO Membrane, so we used a 21″ x 4″ Membrane to save space.  These SM30-4021 Membranes are more expensive and have flow limitations to consider but with  large enough Hp Pump they can be a good solution for a tight installation

Water Maker Hose Run Lengths



A benefit of a modular sailboat watermaker is that the individual water maker modules can be mounted as far apart or as close together on your boat as space dictates (I’m assuming you don’t have a 300ft Mega Yacht and want to spread the Modules from stern to bow).  A plumbing run of 10 feet between the modules will not have a negative effect on system performance.  We oversized the sea water boost pump to supply the high pressure pump, which makes sure your high pressure pump gets plenty of sea water flow.


All SeaMaker water makers come standard with 30ft of low pressure sea water inlet connection tubing, 30ft of low pressure brine discharge tubing and 30ft of low pressure fresh drinking water tubing.  For the high presure connections on the water maker, we provide a 3ft and 5ft high pressure hoses to connect high pressure pump to the RO membrane pressure vessel assembly and then to the remote panel.  Although we have found that most water maker installation can use these standard high pressure hose lenghts, we can supply two 30ft high pressure hoses without a loss in system performance.



Converting a Spectra to a Cruiser RO Water Maker

After years of operating their Spectra DC water maker, Tom contacted Cruise RO Water Makers to talk about converting their Spectra water maker our concept of a “Keep it simple” high output AC 120V unit.

Dear Rich,
We replaced the membranes supplied by you in November 2013 in our Spectra Newport 700. We are now considering replacing the unit with one of yours and I was hoping to use some of the Spectra parts that we already have. We have the seastrainer, 50,20,5 micron filters, FWF filter, pressure vessels ( 2 @ 40″ ) and membranes. I believe we would need the boost pump, high pressure pump and motor and the control panel. Could you provide us with a price to make this conversion and any comments you may have.
Thank you,

Tom’s project highlights the truth that all marine water makers operate on the same principal of delivering a flow of high pressure sea water to a Reverse Osmosis membrane.  The sea water first needs to be prefiltered to remove solids before sending it onto the high pressure pump.  Our water makers use an industry standard stainless steel piston pump to generate the pressure while a unit like Spectra uses a proprietary energy recovery Clark pump.  We control our water maker with manual valves while a unit like Spectra uses electronic controls.  When you strip things down to basics all marine water makers operate on the same basic design criteria but have different approaches to put the principals into practice.

Being a cruiser owned company where the owners and designers answer the phone calls and emails, it is common for us to integrate our parts and “KISS” design concept into other manufacturer’s parts and systems.

As a growing number cruisers are coming to the realization that they need to run their generators to keep up with the power demands of their low output 12/24v DC water makers many are deciding to upgrade their water maker.  As an example, if your 12/24v DC water maker uses a single 40″ RO membrane an upgrade could turn your low output unit in a 20 Gallon per Hour water maker or if like Tom you have two 40″ RO membranes you can have a 30 gallon per hour water maker!

Dear Rich,
With your help we finished the conversion our Spectra Newport 700 water maker on our 48 Krogen to your unit.  We did not use anything electronic since we wanted to use your approach to simplicity. As you can see by the photos the system is simple and easy to service. We are looking forward to many years of trouble free service.