sail-world.com
 
 
News Home Video Gallery Photo Gallery

 

Sail-World.com : DIY – The World's Cheapest Watermaker.

DIY – The World's Cheapest Watermaker.

'Watermaker diagram'   

We were in a Red Sea anchorage, sitting in a magnificent desert seascape, surrounded by a shore of wildly coloured sand, waiting for a gale to pass. Our American cruising friend Bob, on Yacht Aplysia, with his wife Steph have been cruising the world for many years now.

We were sitting on Blackwattle chatting, and the conversation came around to watermakers.

'How much does yours produce?' I asked.

'About 100 litres'

'Wow', I replied, 'We couldn't afford any such luxury – ours produces only 13 litres, but we get along okay.'

I remember Bob's laugh. 'Well, I made it my myself, and it cost very little – come on over this afternoon and I'll draw you a diagram, so you can make one too.'

I was doubtful. 'I'm not very mechanically minded,' I remarked, uncertainly.
'Well, it's actually very easy – you'll see.'

And that's how I came upon this remarkable invention.

For long range cruising, or even a three week holiday, we think a watermaker is an essential item on a boat. The commercial variety range in price from approximately US$3,500 to US$11,000 for a water production rate of 40 -140 litres an hour.

Bob tells me that this design has been passed around the long range cruising community for the past few years. It produces 100 litres per hour, for, with diligent buying, a cost of approximately US$2,000.

Apart from the cost savings, the other great thing about the design is that you can spread the component parts around the boat in any convenient location, some in the engine room, for instance – they don't have to be in one spot, taking up a lot of stowage room, as the commercial variety does.

The diagram shown is a schematic. The parts are all commonplace and easy to obtain from most marine hardware suppliers. The diagram is self explanatory but the following is a quick run through of the component parts:

1.The thru' hull fitting should ideally be a dedicated three quarter inch fitting.

2.A sea strainer or screen connected to the hull fitting by a three quarter inch line, which will continue on to the pressure pump.

3.After the screen, which is intended to remove solids such as seaweed, is an optional feed pump, whose purpose is to ensure that airlocks do not occur in the system.

4.Following the feed pump is a Y-valve with a free tail, which is used for cleaning and pickling the system. This tail usually has a small filter on the bottom, and is inserted in a bucket with the pickling solution.

5.This is followed by a filter which should be a 20-30 micron filter. Some filter housings have a by-pass valve which allows you to eliminate the Y-valve and have the cleaning and pickling pipe going to this system directly.

6.The filter is followed by an optional vacuum gauge, followed by

7.A 1,500 psi high pressure pump, not 2-3000 psi as stated in the diagram, which will be run at 800 psi and can be either electrically or engine driven. CAT pumps are suitable for this purpose.

8.The membrane and pressure vessel, which in this case is a 42 inch long system, is connected to the pump by a high pressure line, which continues to the pressure valve

9.From the membrane, a quarter inch plastic line goes through a flow meter to a Y-valve which can be connected to the water tank for drinkable water, and optionally, to the sink.

10.From the other side of the membrane and pressure vessel connected by a high pressure line is a pressure gauge to 1,000 psi, followed by a

11.Pressure valve with optional bypass at 1,000psi.

12.From this valve, a quarter inch line continues through a flow meter and a

13.Y-valve which will discharge overboard, or to the cleaning bucket.

It is quite a simple unit to build, and with proper maintenance should give 100 litres per hour for many years,

My final comment is that, no matter what watermaker system you have, good care and maintenance is essential to ensuring long life and good drinkable product. . We have regularly cleaned the membrane with both alkaline washes and acid washes when necessary.

Whenever the watermaker is not going to be used for three days we have pickled it to ensure that algae growth does not occur on the membrane.

We have had our watermaker on the boat since 1995, and believe that the careful maintenance is the reason we have had very little trouble. We installed a new high pressure diverting valve this year, 2007.

Editor's Note: If you wish to print the diagram, click on the image below to achieve a larger size




by Ted Nobbs

  

Click on the FB Like link to post this story to your FB wall

http://www.sail-world.com/index.cfm?nid=33568

12:31 AM Wed 9 May 2007 GMT






Click here for printer friendly version
Click here to send us feedback or comments about this story.


News - USA and the World





































America's Cup Book Review: Winging It - Oracle Team USA's comeback *Feature by Richard Gladwell Sail-World.com/nz,




Rolex China Sea Race 2014 - nip and tuck for IRC honours by RHKYC and Guy Nowell, Sail-World Asia, Hong Kong


























HUD Vision: An interview with Afterguard Marine’s Alex Moret *Feature
ISAF Sailing World Cup Hyeres - US Sailing Team ready for action
Volvo Ocean Race - Dongfeng Race Team first official qualifier
Springtime boat buyers need to take care of a few key things
ISAF Match Race Rankings for 16 April 2014
ISAF Sailing World Cup Hyeres – World’s best to race on French Riviera
Rolex China Sea Race – Fleet off to a clean start
America's Cup: Expected de Ridder penalty should be reduced *Feature
World Youth Sailing Week – Second edition officially presented + Video
Rolex China Sea Race - Sailing classic returns
Les Voiles de St Barth – Fired up for battle
CNN Mainsail Down Under for the 75th JJ Giltinan Trophy - 18ft skiffs
Volvo Ocean Race: North Sails on outfitting the Volvo 65
Image gallery: James Cook High's Royal encounter on Steinlager 2 *Feature
Volvo Ocean Race - Maersk Line named shipping partner
Congressional Cup - Victory for Taylor Canfield and crew
SSV Oliver Hazard Perry joins America's Tall Ship fleet + Video
2014 Halifax – Saint-Pierre Ocean Race
Oyster Regatta Antigua - Glorious conditions prevail on final day
WWA Pro Card Qualifier - Pro Cards earned at Freedom Wake Park
Christmas Caribbean Rally - Top class sailors to compete   
Earth Day boater tips   
Anna Tunnicliffe - from CrossFit to Extreme 40's   
Charleston Race Week - Photos by Chris Howell   
Image Gallery: Stratis SL33 flies on the Waitemata   
Audi Melges 20- Sperry Topsider Charleston Race Week - Light final day   
Clipper Round the World Yacht Race - PSP Logistics prepares for USA   
ISAF Sailing World Cup Hyères - Crème of the crop to compete   
Congressional Cup: Luna Rossa makes podium in first event   
Int 14 World Championships 2015 launch new event website   
International Optimist Regatta Clinic and Team Race - Register now!   
Congressional Cup: World top rankers finish that way in Long Beach   
Sperry Top-Sider Charleston Race Week Day 3 finale   
America's Cup: Gino Morrelli outlines the new AC62 design   
Doyle Sails New Zealand signs Andrew Brown as One Design Manager   
America's Cup: Dean Barker's Blog - A sail with the Duke and Duchess *Feature   
29er World Youth Sailing Week Easter regatta - Day 1 and 2 overall   
C Thomas Clagett Jr Memorial Clinic/Regatta - Entries start to roll in   
50th Congressional Cup: See the delayed coverage and media conferences   
Clipper Race 10 Day 27: Closing stages - Qingdao to San Francisco   


For this week's complete news stories select    Last 7 Days
   Search All News
For last month's complete news stories select    Last 30 Days
   Archive News







Sail-World.com  


















Switch Default Region to:

Social Media

Asia

Australia

Canada

Europe

New Zealand

United Kingdom


http://www.sail-world.com/event_images/image/Twitter_logo_small.png http://www.sail-world.com/event_images/image/FaceBook-icon.png  http://www.sail-world.com/event_images/image/RSS-Icon.png

United States

Cruising Northern

Cruising Southern

MarineBusiness World

PowerBoat World

FishingBoating World

 

Contact

Commercial

News

Search

Contact Us

Advertisers Information

Submit news/events

Search Stories/Text

Feedback

Advertisers Directory

Newsletter Archive

Photo Gallery

 

Banner Advertising Details

Newsletter Subscribe

Video Gallery

Policies

 

 

 

Privacy Policy

 

 


Cookie Policy

 

 



This site and its contents are © Copyright TetraMedia and/or the original author, photographer etc. All Rights Reserved.  Photographs are copyright by law.  If you wish to use or buy a photograph contact the photographer directly.
X6XL WAS US