watermaker

[ebs001]

Posters have correctly pointed out that you must have sufficient freshwater for the necessities on board for the duration of the trip. After taking that into account a watermaker allows you the luxury of using water for non necessities like a shower, washing dishes in freshwater etc. While some draw as little as 4 amps (the Pur 40E) they make less water per hour so you just run them longer. A better way to look at watermakers is amps per gallon. I personnally would buy the largest watermaker that I can afford. Any watermaker is a luxury and like most luxuries it is not necessary for survival but it will sure improve your quality of life on an extended cruise. Also be aware they are power hogs so you must have the means of replenishing those amp hours.
I bought a Katdyne 80E for last years cruising in the Bahamas and I was extremely happy with the purchase. We spent 5 months on the hook so the convenience of readily available freshwater was wonderful and sure enhanced our cruising experience. I wouldn't leave home without it.

[GeorgeB]

I did the San Francisco to Oahu trip this summer and here are a couple of observations. We budgeted one gallon of water per day per person. In your case, I calculate 72 gallons, assuming an 18 day passage (What kind of boat are you sailing and will you be in race mode?) In reality, we used much more water as you use more water than you think in cooking and making coffee. And when we were in the tropics, we were also drinking copious amounts of it too. We washed dishes (and ourselves) in salt water, but did fresh water rinses (sparingly). You should plan on using more than the gallon per person per day factor. We also had a Sprectra Ventura 200T watermaker on board. Depending on how you install it, you may not be able to make water close reaching or surfing at speeds (eg. the siphon action along the hull or the system ingesting air/foam and creating a “vapor lock”). We were fortunate insomuch that our thru hull was on the port side (Stb tack most of the way). We could make the 6 gallons per hour rate as long as our boat speed was below ten (we did not have a scoop on the water intake). The watermaker consumed approximately 9 amps/hour and the start-up and shutdown (flush) operations took about 40 minutes to an hour. Needless to say, this was a big energy hog. The other problem is you have to run it every five days unless you pickle it. Pickling is another involved process that eats up a lot of amps too. We ran ours three times during our 12 day passage.

[sailingdog]

One other way to estimate water usage is the way the ISAF does it. IIRC, they require 1 gallon per person per 100 miles for the voyage. Four people with a voyage of 2600 miles would work out to 104 gallons of water. This would give you a bit more of a safety margin than some of the other budgeting methods.

[camaraderie]

I believe the bat is a 33 foot Morgan OutIsland from his earlier posts...not a particularly close winded or fast boat and the distance is at least 2800 miles since you need to get south before heading west too much. That is why I was looking at a minimum of 3 weeks and more likely four.

[sailingdog]

Good point Cam... didn't look at the pilot charts or cornell tonight, since I don't have the books with me. Call it 120 gallons then.

[kennyarmes]

thanks to all i think i will increase my water tank and use the watermaker as a backup

[Omatako]

Originally Posted by camaraderie

At $3k plus installation and spares for a 3 week trip...even that one is pretty steep Andre.

I never considered the possibilty that the boat and it's watermaker were destined for only one more trip . A trip to Maui ordinarily would result in another from there and so on.

Andre

[Jim H]

Sorry to restart an old thread, but I appreciated the quality of this discussion.

I've noticed that some cruisers pack a lot of bottled water (dozens of smaller units per person) in parts of the boat, with a budget of 2-3 per day per person. Tank water is used for cooking, and seawater for washing in the galley sink.

When we talk about putting bladders under settees for more fresh water, would packs of smaller bottled water also make sense, unless they chafed into a leaking mess?

Even when we spend days aboard our boat now, we mostly do the bottled water route, using the bottles for drinking teeth brushing,etc., even though the water system is new and filtered, etc.

[blueskyonmars]

i know i may get flack for telling you this but i use a home unit in my boat. My wife and i have been out for three months at a time and we only hold 80 gallons of water. the home unite works fine and we have never gotten sick from useing it. I still make sure to not depend on it fully and regulate our water use big time. We have gone 6 weeks with out a fresh water shower but hay that crusing. any way here is the link to what i use. its only 300 $

freedrinkingwater.com

[SVAuspicious]

Originally Posted by Jim H

I've noticed that some cruisers pack a lot of bottled water (dozens of smaller units per person) in parts of the boat, with a budget of 2-3 per day per person. Tank water is used for cooking, and seawater for washing in the galley sink.

I've been using tank water for everything for the last three years. I do make an effort to keep the tank and lines clean.

On passages I carry several gallon jugs of drinking water and a large number of smaller bottled water containers (350 or 500ml depending on what I can source). The intent of the jugs and bottles is as both a reserve and a "get-home" supply in the even of a fresh water leak from the tanks.