Hi Dan - It sounds like your problem may be rooted in the HP switch as you sate, but I am curious if anyone on board was able to watch in the engine room to determine if the first event to occur was the high pressure pump shutting down.  

Is it possible that the HP motor capacitors need replacing?   That would be easy to check if you have a capacitance meter.  

Are you drawing the same current with the water maker on as you did in the past? 

Just a thought.  

-James

SV Soteria 

SM2K347

On Nov 11, 2020, at 08:33, Dan Carlson <carlsdan61@...> wrote:

Good morning all,   On sv BeBe, SM#387,  I have the original Dessalator 230v 160LPH water-maker. 

Today was the first time I this season that I have tried to run the water maker (as we were in the muddy Chesapeake Bay with  ready access to decent city water..).  The membranes had been auto-flushed with fresh water for 2 minutes, twice per week while away and I had tested that both the low and HP pumps were functional through the initial start-up sequence. 

I started up the water-maker according to procedure with the pressure control valve initially all the way anti-clockwise (no pressure) and the  product water diverted to a sink faucet.   The low pressure pump kicked on and the low pressure gauge read the typical 12 o-clock reading.  After the typical delay the high pressure pump kicked on and the low pressure guage dropped slightly to about 10:30 (as typical).   After the "green" light came on I began to very slowly increase the pressure with the needle valve.   I stopped when I just reached just below the green zone on the HP gauge and product water began to come out of the faucet.   During this time the product quality lights had gone from green to amber when water began to flow and then back to green after a few seconds of product flow.   I began my usual 30 second count after the product quality light turns green before sampling and testing the water quality with my tongue and TDS meter, before I would then divert the water to the fresh water tank.  All during this time I was watching both the high and low pressure gauges for any fluctuation and none was seen.  I had given the water a taste test and was about to pull the sample for the TDS check when the water-maker shut down with the red "alarm" light.  I turned off the water-maker switch, and the 230v breaker, re-set the pressure control valve, and  checked for any obvious leaks or ? in the engine room.   After those checks I went through the same sequence and had the exact same shutdown approximately 30 seconds after the water quality light went back to green.   On the third try when I turned the water-maker switch back on it went directly to alarm mode. 

After searching the Amel Desallator manuals on-board, and searching this forum I also performed the following troubleshooting: 
1) removed the panel in the locker and checked for any noticeable corrosion, 
2) I checked the fuse in the Desallator control box and it was tight and did not appear to be blown, 
3) checked for any tripped breakers or appearance of any burning around the relays,
3) I checked for any corrosion around the TDS probe and it appeared in good condition. 
4) There is a reference in the Desallator manual to an adjustment screw on the HP switch but neither of the switches in the manual resembled the switch on the back of the panel.   There is a screw in the back of this switch and I made a small attempt to turn it but did not force any movement.  (Picture attached)  Does anyone know if this HP Switch can be adjusted?   Or if it is recommended to remove it and possible clean it out?   Or further tests. 

- At this point I believe that the indications are that there is probably an issue with the HP Switch, but I would like confirmation from others or suggestions of other troubleshooting steps.   
- are there further steps to  either adjust the HP switch or clean the HP switch? 
- In the forum there were comments that owners had disconnected and run the water-maker without the HP switch in the circuit, but I would also like a little more confirmation and advice on how to go about this before taking this next step.   
- Also, at this stage when I turn the water-maker on it goes directly to the Alarm state.  Is there a re-set button that I have not found? or is that indicative of a failed HP switch. 

As background:  twice last season I did have the water-maker shutdown in a similar manner.  Once after it has been running some time (45 minutes? ) and another time shortly after start-up.   In neither case was I immediately attending to the water-maker and it subsequently re-started with no issues and no root cause found at the time. 

Thanks and regards,  Daniel and Lori Carlson on sv BeBe, SM #387
<HP Switch.jpg>