Watermaker Problems - Spectra Failure and a New Install

It's no secret that we've had problems with our Spectra Newport 400 Mk II water maker. Twice in three years we've had to shell out about $5000 to repair it. Trust me, we maintain it correctly. We religiously flush it every 30 days as required and we've never even preserved it, something that can cause issues. It was new when we purchased Calypso 3 years ago. This thing just breaks.

I'll admit, I'm easily seduced by high tech systems with the sweet automatic/electronic features but this one is a fail, in my opinion. Especially when you cruise offshore, your gear cannot be scheduled for a regular repair. It needs to work. Let's get into it.

Spectra support answers the phone when you call and they do take you through a emailed troubleshooting process but it's really more like a repeating algorithm that goes nowhere in the end. It took two weeks of daily emails back and forth to get nothing done. And you get one step per day, you'll get a response tomorrow and so on.

Then we contacted the "Spectra Guy" of Florida, J.T. Halden who was super awesome, friendly and helpful. In one step he was able to identify the first issue (below) but we still couldn't break the issue down to a single component over the phone. We ended up ordering all the parts (again) and will replace the parts in order until it's repaired.

Just some background, I am a Powerplants and Fuel Systems mechanic on F/A-18 A/B/C and D fighter aircraft. I'm accustomed to working with high tech and complex systems, so this shouldn't be too difficult. Right?

Let's break it down Barney Style.

The Discrepancy:

In both instances we've had an issue it starts with a loud feed pump while operating, which is air cavitation inside the pump, and we've had reduced water flow. The feed water (raw water going through the system), the brine discharge water and the product water (the fresh water we're making) are all low. They're low by a lot. The product water should be up around 15 gph, we're currently at 7 gph and falling. The PPMs in the product water are also higher than usual. Normally at 300ppm, were around 650ppm. Probably due to the low pressure.

I first checked all voltage throughout the system, it all was great. Over 12.5V everywhere so we're moving on.

Step 1. The Boost Pump.

This little guy is the first part in the system. The raw water comes in a nearby through hull and goes through that strainer to clean it from weeds, etc. Then the boost pump (black pump attached to the right side) pushes the water further to the pre-filters and the feed pump.

The first step was to check that this little boost pump was pushing water, it was not. It was getting the correct voltage and the little magnetic impeller inside was spinning but water wasn't flowing. It must've been weak. How did I know that water wasn't flowing? Mr. Halden recommended removing one of the pre filters where this pumps to and then to run the water maker in manual. That powers the boost pump and we should have water flow freely to the pre-filter. We didn't, no water existed at the pre-filter. So, I ordered a new pump! Of course, Spectra didn't have any pumps, they are all on backorder somehow. So I found an off brand pump to buy. I installed it, and boom! Water is pushed to the pre-filters like a champ! Did it fix the problem though? Nope...Next!

Step 2. The pre filters and feed pump.

This is the main housing for the water maker. This houses the circuit board, the pre-filters and the feed pump inside. The Boost Pump that we just repaired above sends water to the rear pre-filter (blue lid on the right), first through the 20 micron and then through the 5 micron pre-filter (closer in the photo) before continuing on to the Feed Pump inside the white box itself.

I ordered the feed pump, I received half of it. Spectra had the lower section in stock, actually called a Vane Pump which is the pump itself. The motor that drives the pump is out of stock and backordered. See a trend? I wasn't happy when I got the box and only half of the pump was there. Then finding out that they send them in two parts and the motor for it is about $2500.00 more, this wasn't mentioned and I didn't order it when they finally did mention it. It wouldn't be in stock for months anyway. Spectra said they recommend trying the lower part first since they can't get a motor, then to replace the motor as a last resort. It's pretty crazy that their troubleshooting is for you to