How to maintain a dormant water maker?

[RickyEM]

How do folks maintain a dormant water maker, one that is not used for years?

I have received different advice from the manufacturer of my unit Parker (Village Marine Little wonder) from change preservative every 3-6 months to fresh water flush every week (that too much preservative can damage the unit).

Of course, I don’t want to do anything on too frequent a basis!

I left preservative in my unit for last two years doing nothing, and have been told that my membrane is probably damaged as a result and that I should just wait until I recommission the unit for use and replace the membrane. In that case, should I just let the old preservative sit until I replace the membrane? Replace preservative every six months? Fresh water flush every week (not there every week so can’t do that)….

[belizesailor]

At 2 years, I agree the membrane is probably shot. Some seals may be ruined too. No way to know except to fire it up and test it (purge it first of course). You need to refresh the pickling soluton anyway so I would go that route.

Propylene Glycol is becoming a favorite for picklng because it is easier on seals etc.

[RickyEM]

Thanks

I am assuming I will have to replace the membrane when I want to use it again.

So I do a fresh water flush and put in new preservative now; what should I do in say 6 months. Continual cycles of new preservative for a membrane that is probably shot?

A tech guy at Village Marine told me

"I would recommend fresh water flushing once a week instead of preserving the unit. The preservative chemical is food based and safe, but if it is used numerous times it could do more harm to the unit. Fresh water flushing is the best option for a dormant system. "

But I can't always do a fresh water flush every week as sometimes I am away from the boat for months...

[DeepFrz]

You may be interested in this video.

https://www.youtube.com/watch?v=JDi6Ld5o8ns

[hellosailor]

Sounds like it would be less work and less money in the long run to decommission the unit and take it apart. Throw out the old membrane, clean and dry everything, close it up to prevent critters from nesting in it. Then when you want to put it back in use, buy a set of all new o-rings and a new membrane. Since o-rings degrade over time and probably will need to be replaced at some point regardless of the care...
Break it down, seal it up, then you can ignore it for however long is necessary, and start with a reliable unit when you re-commission it.

[senormechanico]

My Spectra is at least 17 yrs old.
I use it every summer in the PNW for several months.
I purge it with product water in the fall.
I refresh it in the spring with product water.
I use it every summer in the PNW for several months.

Rinse and repeat.
Original membrane and it puts out to spec.
TDS runs in decreasing numbers from 200 PPM after about 3 minutes from startup.
Then I save the water.
If I run it for an hour, I get down to around 120 PPM.

What's not to like about this scenario?
Granted, I'm not in the tropics, but...

[Kenomac]

Originally Posted by belizesailor

At 2 years, I agree the membrane is probably shot. Some seals may be ruined too. No way to know except to fire it up and test it (purge it first of course). You need to refresh the pickling soluton anyway so I would go that route.

Propylene Glycol is becoming a favorite for picklng because it is easier on seals etc.

Ours was pickled with the Spectra preservative for six years continuously with no ill effect on the membrane. We unpickled it, and used it for 18 months without an issue with ppm tests in 300-500 range. Well within the acceptable range.

Eventually, we rebuilt that unit and changed the membrane at that time.

[JDeachman]

Senormechanico: What is "product water"? Is this different from pickling.

[zstine]

Originally Posted by softdown

....

I would try to flush it with chlorinated tap water before storage. If you don't have chlorinated water handy, use a little bleach in some clean water.....

NO BLEACH OR CHLORINE! The chlorine will destroy the membrane. You never run bleach/chlorine through an RO membrane and that is why most manufactures put a carbon filter on the water flush line. There's a chance yours is not dead. As others have said, sometimes a pickled unit can go years without a problem. You don't know until you test it. I'm no expert, but I would flush with fresh water, then re-pickle with either the manufacture's solution or 100% food grade propylene glycol... maybe run a test with some salt water and see if it is good before flush and pickling?

[Kenomac]

Originally Posted by softdown

I would try to flush it with chlorinated tap water before storage. If you don't have chlorinated water handy, use a little bleach in some clean water. I would think iodine would also work.

You are trying to kill off a runaway bacterial explosion while it is stored. There are likely a number of products that would work. The question is what is safe for the membrane. Chlorine and mild bleach are ok with normal membranes.

NO, NO, NO!
A 100% sure way to kill your membrane.

[softdown]

Originally Posted by Kenomac

NO, NO, NO!
A 100% sure way to kill your membrane.

Do tell........I have professionally installed many, many R/O systems and membranes. Adams Aquatics, thats me, has been running for 24 years now. Installing and maintaining R/O for 23 of those years.

And your professional water purification background is? Let me guess....
https://en.wikipedia.org/wiki/Desalination

[Kenomac]

Originally Posted by softdown

Do tell........I have professionally installed many, many R/O systems and membranes. Adams Aquatics, thats me, has been running for 24 years now. Installing and maintaining R/O for 23 of those years.

And your professional water purification background is? Let me guess....
https://en.wikipedia.org/wiki/Desalination

I place my trust in the Spectra recommendations aka Tellie on this forum and Rich at RO on this forum.

Please explain why your recommendations differ from the other manufacturer's recommendations by 180 degrees? Why do you recommend the exact opposite?

[Cheechako]

Your membrane may be shot, but often that's not a huge deal unless your manufacturer uses a proprietary one that they overcharge for. I worry a bit about leaving the pickling solution in the hi pressure pump. Will it corrode inside the piston pump?
If I were leaving a unit for a very long time I would consider removing the membrane, pickling it in a sealed bag, and flushing the system with fresh water or maybe even "safe" anti freeze left in for storage.

[donradcliffe]

Originally Posted by softdown

Do tell........I have professionally installed many, many R/O systems and membranes. Adams Aquatics, thats me, has been running for 24 years now. Installing and maintaining R/O for 23 of those years.

And your professional water purification background is? Let me guess....
https://en.wikipedia.org/wiki/Desalination

You may install R/O systems, but the rest of us can read.

From the Katadyn manual on preserving the membrane

(Caution: Never use chlorinated freshwater. This may damage the membrane.)

Those instructions weren't in the manual 20 years ago and it cost me a set of membranes.

[Tellie]

opc orn: I'll let Rich, he loves this kind of stuff.opcorn :