Watermaker Service/Cleaning RO membranes

[oceanjake]

I have no experience with watermaker service. My boat has a village marine LTM-800 and the system pressure has been increasing over time and now suddenly is running at almost zero pressure without a drop in salinity. I'm going to dig into things....kind of sounds like the membranes are shot and maybe have holes in them? But...going through things, what steps should one take to give a system a once over? What do you clean membranes with in the event that they are intact?

 

[Pascal]

With zero pressure you re not going to get any drop in salinity. What happens when you turn the regulator to increase pressure? gauge doesnt move? Any change in sound?

In pressure regulation is automatic, try to set it to manual mode

 

[Dan Mapes]

Zero pressure on the gauge says the regulator valve is not closing. The membranes are being bypassed. If the pressure control is automatic that part of the system has failed or its controller is inoperative. If you can go manual, ensure you bring the pressure up slowly. Do not start the pumps with the bypass valve set to production mode.

 

[oceanjake]

I can tell from these replies that I need an education in operation of these things.

The equipment I have has two valves. Each valve has a setting for cleaning and production. I was told to start with both in cleaning, then turn one to production and follow with the second. When the second valve was turned, the pressure on the gauge used to go from 0 to around 800 relatively quickly. Now, it will sometimes go up and sometimes not. In either case there is an audible difference in the pump that is proportional to the reading on the valve. Sometimes it will stay at zero regardless.

The system has an electronic bypass valve that diverts water to the holding tank when it reads below 500ppm. Normally it starts out around 1900ppm and works down from there. Currently it's flashing "1" which indicates high salinity (above 2000).

Since the system was not pickled when I purchased the boat and I know the previous owner was not religious about starting and cleaning it I figure I should at least learn about what I have and take it apart and look for failure over the harsh california winter.

I really appreciate the advise of those that understand this type of equipment. Great forum.