Stump the Chump - a Water Maker Failure

Stump the Chump - a Water Maker Failure

Friday 19th - Sunday 21st January 2024

There used to be a fun radio show on NPR called “Car Talk” and the two brothers who hosted it had a section in the program where they would follow up with a listener, who had called in some weeks previously with a perplexing car problem, and see if they got the solution correct. They called this section “Stump the Chump”. I need a marine program like “Car Talk” to phone into about our water maker (desalinator / reverse osmosis system). 

Up until this point we have been going into marinas to fill up with fresh water, but in Dominica, our next destination, this won’t be possible. Our Spectra 380c water maker is original to the boat and as such is 25 years old, well beyond life expectancy, plus it’s been over 5 years since we last used the system. We did “pickle” the system back in 2018 (i.e. flush through with fresh water followed by RV antifreeze) but I was expecting some problems getting it up and running, and was even prepared for the likely scenario that the critical membrane was shot. It took me some time reading over the instruction manuals to remind myself how to get it going. The former owner installed an automatic operating system that by all accounts was a complete nightmare. It caused him endless problems and he hated it! However, there is a manual override and the basic system is pretty simple - two priming pumps in parallel (only one of which is needed), a high pressure Clark pump, the membrane and a bunch of hoses, filters and manual valves to select input sources (seawater or from a bucket) and output destination (overboard or to the collection). The first thing to do was simply switch on one or other (or both) of the priming pumps and circulate seawater throughout the system to clean out the old “pickling” fluids. However, when I switched them on … nothing! Some of the electrical connections looked less than stellar, so I cleaned those up, and made sure the12v supply was okay. In doing so I burned out a 15A mini-auto fuse in the control unit, for which I had no spare, but was able to source at the local hardware store. With that replaced I confirmed the power supply …  but still nothing. I subsequently took apart one of the pumps, which looked fine on the water side of things and also on the electric motor side. It appears that perhaps some capacitor or other electronic gizmo inside the pump has burned out, but it’s surprising that both pumps would fail. At this point I have closed the lid on the unit and given up. I am stumped! Any ideas out there?

Cotinga has two fresh water tanks that hold 120 gallons. When Gloria and I are being frugal, we can make that last 3 weeks or so. We have now taken the low tech approach and purchased two additional 5 gallon ferry cans, to add to the two we already owned. (We also have a couple of collapsible jerry cans - great idea, but full of holes, leak like sieves!) Anyway we took our containers into the commercial dock and purchased 100 liters of water (for 3 euros), so now have full tanks plus some extra. We plan to just keep filling jerry cans as often as we can. 

Tomorrow we are heading south to Dominica. It’s about a 20 nm passage and after our experience getting here we are quite nervous. The winds which are currently 15-20 knots from the south-east are supposed to back to north-east by tomorrow morning, which will be helpful in putting us on a a beam reach, but the winds also increase to 20-25 knots with seas of 6ft plus, which could make it gnarly. We would be happy to stay a little longer in Les Saintes but the conditions are supposed to intensify further during the week, and the dinghy ride to town is challenging enough under current conditions. We have not seen a free mooring off the town the whole time we have been here.

Our broader plan is to cruise Dominica and Martinique for the next few weeks, then make our way back north to Antigua for end March, leave Cotinga in Jolly Harbor marina and fly home for the first two weeks in April. We will then resume our journey south to Grenada. So this will give us an opportunity to return to our favorite spots, including here, and hopefully hit some destinations we have missed.

Mike

Our Water Maker ... the membrane is the long tube at the top, the high-pressure Clark pump is the short tube under the Spectra label and the two black cylinders below are the priming pumps. 

A view of Ilet a Cabrit from the main island. we are moored with the group of boats to the left of the Island (iPhone photo)

An evening view of the Bourg des Saints, the main town with the 60-boat mooring field in front, shot from the top of Ilet a Cabrit.

The beautiful Baie de Pont-Pierre on the north-east side of the main island

Window shutters in an old, rundown building

A cruise liner anchored off Ilet a Cabrit after sunset ... shot from the top of the island with a 30 s exposure and varying the focal length of the lens

A large, 5-spreader sailboat anchored in teh channel off Ilet a Cabrit