Water Maker Long Term Non Use

[mcerdos]

I purchased a boat with a 15GPH engine driven water maker. I do not plan to use this feature for at least two years. But when I do use it, I want it to operate correctly. I do not really want to pickle with with chemicals. My thought is to remove the membrane and filters and replace them with new ones when I want to reboot the system. Any issues with this?

The manufacturer's site only speaks to pickling the membrane with chemicals for up to 6 months. I would prefer not to have poison anywhere in my water system.

Thanks for the advice.

[FSMike]

If the boat's going to be in the water in a suitable area then use the watermaker regularly even if you don't need it. If that's not possible for a two year period prayer will probably be necessary. Even pickling according to the mfg's instructions is like as not to fail after that length of time.

[Astrid]

My thought is to remove the membrane and filters and replace them with new ones when I want to reboot the system. Any issues with this?

I don't see anything wrong with that plan. I believe Tellie is our forum expert on watermakers and if he chimes in, pay close attention to his advice.

[s/v Jedi]

I don't think you need to view the pickling solution as poison.

We have not pickled our membranes ever. When not used, we just rinse them with fresh water; the first time very thoroughly, then every 4-6 weeks repeat. Manufacturers will only allow 2-week periods under warranty.

You can't kep a new membrane in it's packaging for 2 years. The packaging holds pickling solution so needs refreshing every 6 months.

cheers,
Nick.

[Astrid]

True the membranes do have a shelf life, so to speak. Use them or lose them.

[Tellie]

Originally Posted by mcerdos

I purchased a boat with a 15GPH engine driven water maker. I do not plan to use this feature for at least two years. But when I do use it, I want it to operate correctly. I do not really want to pickle with with chemicals. My thought is to remove the membrane and filters and replace them with new ones when I want to reboot the system. Any issues with this?

The manufacturer's site only speaks to pickling the membrane with chemicals for up to 6 months. I would prefer not to have poison anywhere in my water system.

Thanks for the advice.

Hi mcerdos,
As s/vJedi says "Don't view the pickling solution as poison" But this is my advice. First run the system normally to make sure it is in good working order if you haven't already. Put in new pre-filters. Purchase about two gallons of Propylene Glycol-100. ( NOT Ethylene Glycol ) Give your system a good long freshwater flush first, then re-circulate the PG-100 throughout the system for about 30 minutes under no pressure. This will store your system for at least a year. The beginning of the second year just repeat this procedure again. I've had many watermakers that have been stored this way for over two years and were fine when re-commissioned. But the condition of the membranes were very good at the onset. Even if yours are older than five years and you had to re-place them in two years when you start to use your watermaker, I'd still highly recommend you do this. The reason is that PG-100 has great lubricating properties for the rest of your system, it's seals, O-rings, valves, plungers etc. Also, it will prevent any nasty growth inside the system because, no matter how hard you try, you will never get it totally dry inside if you put it in storage without the membranes. If you pull out your existing membranes and leave the rest of the system semi dry, in two years time just sitting there, chances are very good you'll have many other issues with the system besides the membranes when you re-commission the unit. Also, unless the membranes you take out are not 100% flooded all the time with a pickling solution they will dry out in a matter of days making them worthless. When you are ready to re-commission your unit just give it a good 30 minute flush under no pressure and you'll be fine. PG-100 is non toxic even if a minute trace is still in the system.

[chrisjs]

We had the same problem after our Bahamas trip. The RO membrane ran for 6 months and while still good will not be needed for a couple of years. Worst case it will need to be replaced. But in an effort to save it, after flushing the system with fresh water (no chlorine) I removed the cartridge housing with the membrane inside and filled the entire assembly with 2% sodium bisulphite. I have subsequently replaced the sodium bisulphite solution a couple of times and the assembly is now sealed tight with fresh bisulphite solution for long term storage in a cool place. Apparently, Filmtec membranes can be frozen and thawed carefully before use. Incidentally, sodium bisulphite solution is perfectly safe and routinely used for sterilizing baby's bottles and home-made preservative jars, wine and beer bottles etc., though I would not suggest drinking it!!!
Chris S.

[Amapola]

Membranes have a short shelf life so manufacturers don't stock large quantities. My dealer recommends not replacing the membranes until you are ready to use them.

[RDW]

Is PG 100 ok in an environment below freezing?

[Tellie]

Originally Posted by RDW

Is PG 100 ok in an environment below freezing?

Yes, it is an antifreeze solution used mainly for that purpose. In fact if the watermaker is going to be stored in climates that deep freeze it's exactly what you want to use.

[chrisjs]

I would check the use of any propylene glycol antifreeze carefully against the manufacturer's spec for the membrane. I believe that Filmtec (DOW) advises specifically against using antifreeze. They do indicate that freezing the membrane is OK. Problem is it is not OK to freeze the complete RO system. Consequently, I remove the RO membrane in its pressure vessel and store that separate from the drained down system.

[Tellie]

Originally Posted by chrisjs

I would check the use of any propylene glycol antifreeze carefully against the manufacturer's spec for the membrane. I believe that Filmtec (DOW) advises specifically against using antifreeze. They do indicate that freezing the membrane is OK. Problem is it is not OK to freeze the complete RO system. Consequently, I remove the RO membrane in its pressure vessel and store that separate from the drained down system.

While I agree caution is always a good idea, I have stored hundreds of watermakers and membranes with PG. Dow/Filmtec ships their membranes in a 18% by weight PG solution and a 1% by weight soduim metabisulfite solution. By far PG out performs any other solutions that even the major watermaker manufacturers use or produce. Spectra even prefers it over their own propriatary solution. But anyone who goes to the time and effort to remove their membrane vessels for storage is going to be someone who takes extra ordinary care of their watermaker and will probably have very few problems with it.
I like to experiment a bit. I'm certainly not doing so under any strict scientific standards, but I believe they represent a more real world enviroment. I have ten four inch tubes which I keep lightly used membranes in. I used to use metabisulfite a few years ago. Now I use exclusively PG keeping them totally immersed in a vertical position. I date them and record their TDS levels before storage. I have brought a few of them out after over a year of storage then bench tested them. I have yet to have one fail or have any significant difference in TDS readings before re-storing them. Not so with metabisulfite. Again it's not a scientific study, but in my results I have so many fewer long term customer issues using PG over SB.

[Matt sachs]

I know nothing about watermakers, but I think its important to repeat...Do NOT use Ethylene Glycol (car antifreeze). It can kill you. Propolene Glycol is not the same as Ethylene Glycol.

[missnmountains]

We pickled ours for a year once using the RV antifreeze. This stuff is used for all water systems on boats and RVs and is NOT poisonous. Our boat is kept in SW Florida.

Upon putting the WM back into service, I back flushed a few times, ran water for about 15 minutes out of our test port, and tested with a TDS meter. It was less than 200 PPM. And luckily tasted fine.

Ken

[Matt sachs]

Typically the primary ingredient in RV antifreeze is Ethyl Alcohol. Mix it with a little orange juice and lets party....