Katadyn Powersurvivor 80E
We purchased a rebuilt Katadyn 80E watermaker for about $2000 and were assured that it had been totally rebuilt with new membranes. I would not recommend buying used equipment like this again, and we would have been better off buying a brand new unit for about $3900.
When we came to use the watermaker on the Atlantic crossing it gave disappointing results. We later found out that it had been rebuilt with the wrong membranes, and $540 and a season later, we finally had good water after replacing the membranes with genuine Katadyn parts.
The unit makes about 3.5 gallons (13.32 liters) per hour and we would run it, while the engine was running about 2 hours per day to fill a separate 30 liter bladder tank under the galley sink. We could then transfer it to the main tanks or use it directly out of the bladder tank.
We had a valve under the sink that would allow the first few minutes of reject water to dump out of a spigot into the sink and then divert to the tank once we were sure we had good water.
We bought a Hanna TDS (Total Dissolved Solids) meter with which to test the salinity of the water for about $15. You fill the cap with the water to be tested, and then dip in the TDS meter to measure the PPM (parts per million) of solids remaining in the water.
When you first switch on the watermaker the TDS is up at about 990 PPM (pretty salty) and gradually reduces over the next few minutes to about 200 PPM or less which is good water. Regular tap water off the dock usually weighed in around 500 PPM and bottled (bought) water at around 90 PPM.
As a matter of interest, distilled or deionized battery water varied at around 22 - 68 PPM.
One of the most critical components of the watermaker installation is the prefilter, which needs to be installed where it is convenient to change the filter daily. Mine was mounted on a bulkhead directly under the cockpit seat. Almost every morning I would unscrew the filter, pour out the water and put in yesterday's, cleaned, and sun dried filter.
I would tie the tail of a cockpit sheet through the old filter and throw it overboard (while underway) to give it a thorough rinsing. Then I would let it sit in the sun to dry to become tomorrow's new filter.
I think I am still on the same two filters after two long seasons, even though I have many extras onboard.
We only made water when at sea in clean water.
If you are going to be in a marina or not able to use the watermaker for a week, you should "pickle" it. This consists of adding a spoon of biocide to a bucket of non-chlorine water (either water maker water, or even sea water,but not tap water) and then switching the cleaning valve and 3 way input valve to allow you to suck the biocide from the bucket rather than from the sea. It only takes a minute to do if the three way valve and pick up tube is in a good location.
When in use, volumes of water pass through the watermaker, but only a trickle of fresh is saved. The remaining reject brine water I routed to a breather overflow vent in the side of the cockpit, just above the cockpit drain. This way I could see, from the waterflow , that the watermaker was running properly.
Before leaving Florida I bought a cruisers service kit which consists of extra filters, spare parts and O-rings, extra biocide and some special membrane cleaner. Under normal circumstances, you should not need to clean the membranes for many years and is not recommended unless you really have to.
We found that 30 liters a day of water was quite sufficient for cooking, washing dishes, and some very conservative and quick showers for the two of us.
With guests onboard we normally recommended a swim, with a shampoo soap up, followed by another swim, and maybe a rinse with the sun shower on deck.
We also chose to use mostly bought, bottled water for drinking, though we could have used watermaker water.
Howard [ Just Imagine ] 01-Jan-2008
Plumbing Diagram (Technical)
The diagram below is less complicated to operate than it looks.
The electric pump draws the water from one of three main tanks in the salon, or, via a 3 way valve, directly from the watermaker day tank.
The pump can be used to transfer water from the day tank to the main tank or vice versa using the 3 way valve and one of the other two transfer valves.
For the first few minutes, the reject product water from the watermaker goes to a spigot in the galley sink where it can be tested. Once the water is tested OK, the three way, reject valve is switched to allow the water to go to the 30L bladder, day tank.
When the day tank is full, it overflows through the hand pump in the galley sink. The hand pump can also be used to draw water from the day tank, or it could be transferred to the main tanks.
Howard [ Just Imagine ] 12-Mar-2008