SCHENKER WATERMAKER TECH CLASS 5 (SERIES):

(The Doomsday Switch aka The Bypass Switch)

As a KISS GUY “Keep It Simple Stupid”, I must admit that I like being able to start, stop and control the watermaker from the comfort of the chart table. While cruising with my Cruise RO Piston Pump watermaker, I had to crawl into cockpit lazarette to manually adjust system pressures at the start and stop of each run. But my body just doesn’t get into and out of that locker as easily as I once did. So I’ve grown to appreciate the simple push button on/off controls of the Schenker Basic panel and every time I commission a Schenker with a Touch Screen control panel, it just puts a smile on my face at the ease of operation. As a tech/data nerd, I also love seeing all the system operating data the Touch Screen control panel displays. I will even let leak out here for you tech enthusiasts that the Touch Screen panel models will soon interface with the Raymarine/Garmin/B&G/Simrad Multi-Function Displays, so even more data and ease of operation is coming.

Electronics are great, but what happens if they Fail? Do you lose the ability to make water if a Touch Screen, Circuit Board or MFD goes out in the middle of no-where? That’s what we will be addressing in today Schenker Tech Class, what I like to call “The Doomsday Switch”.

Now the Schenker team in Italy officially calls this the “Bypass Switch” inside the electrical control box and may not like my renaming it in such dramatic terms, but I think my name is more memorable if that “Doomsday” scenario of an electronic failure was to ever happen with your watermaker controls.

Since Schenker watermakers don’t require any user pressure adjustment, all the watermaker needs to make water in a bare bones form is a working: Feed Pump, ERS, 5-Micron Prefilter and Accumulator. As convenient and cool as all the system controls are to automating the watermaker and making it easy to run and maintain, you can bypass all of the system controls (hence the more professional name of “Bypass Switch”) and make water completely manually if you ever need to do so. The “Bypass Switch” also is used during the Pickling and Membrane cleaning process and is also quite handy when troubleshooting and venting air out of the system to keep the unit from shutting down due to an “Under Pressure Alarm”. But it also gives you an important manual back-up if you were to ever lose the system electronics.

I was recently working with a cruiser in the Bahamas who had a “water intrusion incident” that flooded the electrical control box on his ZEN30. The watermaker circuit board was fried and as we all know, getting parts to the Bahamas is a challenge, to say the least. So with a little help, the cruiser was able to run his watermaker manually, by using the Bypass Switch. He left the Bypass Switch in the on Position so that when he turned on his watermaker breaker, the Feed Pump turned on and he was able to make water.

Now, some Words of Caution about running in Bypass or “Doomsday” Mode. You have bypassed your Pressure Sensors so if there is a blockage in your ERS or watermaker plumbing lines, bad things can happen, like over pressurizing lines causing hose clamps to pop-off and spray water on your expensive Quatro 3000 Inverter/Charter (been there, done that). So when running in Bypass Mode, you MUST pay attention to the watermakers operation especially during system start-up to make sure everything is working correctly. On units with Auto Product Water Diversion to send the product water to your ships tank, the diversion valve won’t function, so you will need to re-route the product water manually to your ships tank. And finally, when running in the Bypass Mode, you lose your ability to automatically fresh water flush the watermaker at the end of the run or by using the Autoflush timer feature. So you now need to fresh water flush the watermaker manually. But this is easy because also on the control board you will find an EV Bypass Switch (or Fresh Water Flush Solenoid Bypass Switch). When you flip this switch it sends power to the solenoid valve and will fresh water flush the system for you manually with your feed pump running, just like normal.

So in the famous words of Captain Ron that we all know to be true: “If it’s gonna happen, it’s gonna happen out there boss”. But at least if it happens to your Schenker watermaker controls, you will know how to deal with it and be able to keep making water until you can get to civilization to make repairs.

Cheers Rich Boren aka “Cruise RO Rich” Rich@CruiserServices.com

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