Trying to fix a Katadyn water maker

[HisseO]

Hi all,

I'm trying to put back to life an PowerSurvivor-80 from PUR/Katadyn.
This is an old unit that I don't have any history on how it was maintained.
I'm struggling to identify if the failed part is the membrane or if the pump is not putting enough pressure.

Here is the tests I have done, you will understand why the answer to the above question seems not so obvious (at least for me):

1/ I'm running the test at home with tanks of Tap water and another tank of Sea water.
2/ Motor seems running fine and Amp consumption is inline with expectation
3/ Self priming works, and after couple of minutes no more bubble are returned from the membranes
4/ When running the PowerSurvivor from Tap water tank, The Product Freshwater Output is about 12L/h (3gal/h), inline with the specs.
5/ But when running the PowerSurvivor from Sea water tank, there is no product of Freshwater on output. eventually I get couple of drops after minutes, and those drops are salty.

I know that Salt water requires more pressure, but how can I figure out if I need to replace the membrane or if I need to service the pump?

Thanks in advance for your help.
FreD.

[GordMay]

Greetings and welcome aboard the CF, Fred.

Gary Albers ("ishipaco") literally wrote the book, “How To Survive With A
PowerSurvivor Watermaker”

"How To Survive With A PowerSurvivor Watermaker"
A Mariner’s Guide to the Installation, Use, Maintenance and Service
of PUR Reverse Osmosis Watermakers from Recovery Engineering, Inc.
By
Gary E. Albers, aboard S/V 'ISHI'
Here ➥ https://www.cruisersforum.com/forums...?do=file&id=38
Or ➥ https://manualzilla.com/doc/6007661/watermaker-book

[HisseO]

Thanks Gord, this is indeed great source of information, and I already had this book and went through it, but can't find answer to my particular problem :-(

[donradcliffe]

The pressure required to produce RO flow is greater than the osmotic pressure, which is proportional to the concentration of the salt in the sea water tank. Typical sea water RO operating pressures are 800 psi. Are you using real sea water, or did you mix up a salt solution?

There is no pressure control on the Katadyn pump, and running it on tap water is bad for the membrane, but you should have gotten a much higher flow rate.

The membrane can also be ruined by exposure to chlorine in tap water.

https://www.wqa.org/Portals/0/Techni...ts/2016_RO.pdf

[davil]

have you taken the membrane out of the case?
been an old unit and no record of use/maintenance more likely the membrane is gone for lack of care.
I am in the process of plumbing my Power Survivor 40 that I owned for about 22 years in two different boats.
I have it pickled for the last few years and I thought the membrane should be ok
IT WAS NOT!!!looked nice and shining BUT on touch will fall apart.
I rebuilt the unit with the rebuild kit and found the same results as you. That is when I opened the casing and found the membrane was no good!
Have to replace the membrane and now all is well.
good luck

[Lepke]

You need about 900 psi to make water from sea water. Usually there's a gauge, if not add one. For membrane long life, when starting, pressure needs to be increased gradually. Membranes need to be pickled if unused for more than a few days. Membranes can become restricted with organic or mineral deposits, both can be removed with proper cleaning unless they've been there a long time. When cleaning, don't exceed membrane's allowable temperature.

Membranes are rated at 77°F. Colder water, less output, warmer water, more.

[HisseO]

Originally Posted by donradcliffe

The pressure required to produce RO flow is greater than the osmotic pressure, which is proportional to the concentration of the salt in the sea water tank. Typical sea water RO operating pressures are 800 psi. Are you using real sea water, or did you mix up a salt solution?

There is no pressure control on the Katadyn pump, and running it on tap water is bad for the membrane, but you should have gotten a much higher flow rate.

The membrane can also be ruined by exposure to chlorine in tap water.

https://www.wqa.org/Portals/0/Techni...ts/2016_RO.pdf

I'm running with real sea water I collected 2x days ago.
In order to not take risk with chlore with tap water, I have left the tap water tank outside for 2x days, so hopefully the remaining chlorine was destroyed by the sun.
Are you saying that with the tap water I should have got much more water produced?
=> the problem could be a clogged membrane or not enough pressure.
Can a membrane get clogged?
Because the unit was left years unused, it's possible the membrane eventually dried. What would be the result with a dried membrane?

[GordMay]

J.T. HALDEN* of Halden Marine Service is one our CF resident watermaker experts. As a dealer, he’s very familiar with Spectra / Katadyn watermakers.
* aka: Tellie https://www.cruisersforum.com/forums...llie-9014.html

Halden Marine Service
293 SW 33 St. Ft. Lauderdale, Florida 33315, USA
Phone: +1 (954) 515-7077
Email: haldenmarineservice@yahoo.com
Private message on CF: https://www.cruisersforum.com/forums...o=newpm&u=9014

[HisseO]

Originally Posted by Lepke

You need about 900 psi to make water from sea water. Usually there's a gauge, if not add one. For membrane long life, when starting, pressure needs to be increased gradually. Membranes need to be pickled if unused for more than a few days. Membranes can become restricted with organic or mineral deposits, both can be removed with proper cleaning unless they've been there a long time. When cleaning, don't exceed membrane's allowable temperature.

Membranes are rated at 77°F. Colder water, less output, warmer water, more.

Thanks that's one of the problem with the simple PowerSurvivor system, there is no gauge, and I don't see any simple way to fit one. This is this unit with 2x membrane in series.
Obviously with a gauge I could determine if the pump is putting the expected 800psi.

[HisseO]

Originally Posted by davil

have you taken the membrane out of the case?
been an old unit and no record of use/maintenance more likely the membrane is gone for lack of care.
I am in the process of plumbing my Power Survivor 40 that I owned for about 22 years in two different boats.
I have it pickled for the last few years and I thought the membrane should be ok
IT WAS NOT!!!looked nice and shining BUT on touch will fall apart.
I rebuilt the unit with the rebuild kit and found the same results as you. That is when I opened the casing and found the membrane was no good!
Have to replace the membrane and now all is well.
good luck

Yes I have taken one of the two membrane out of the case (this unit has 2x membranes in serial) to check, and so far the membrane looks visually in good shape.
Having the membrane in hand is there a visible sign of failure I could see?
When you say on touch will fall apart, what does it mean? What should I look for?
Will do the same with the second membrane...

[davil]

Originally Posted by HisseO

Yes I have taken one of the two membrane out of the case (this unit has 2x membranes in serial) to check, and so far the membrane looks visually in good shape.
Having the membrane in hand is there a visible sign of failure I could see?
When you say on touch will fall apart, what does it mean? What should I look for?
Will do the same with the second membrane...

==========================================
the 40 unit has only one membrane so was easier to check one.
On inspection looked yellow on color (good) but when I touched started to peel off.
Not a scientific method BUT good enough for me.
Again, because you do not have any records the membrane remains the prime suspect in my view.
I think will be advisable to open the second membrane housing to check that membrane at least visually.
I scratched the surface with care and that is when just peeled off.

[davil]

well going back to my boat and try to finish the plumbing of the PowerSurvivor.
Incidentally, tap water as mentioned previously is not a good idea, I bought couple gallons of pure water in the supermarket for testing, use both the purified output hose AND the saline waste output into the containers and reuse it, I am cheap but after buying a new membrane did not want to risk it.

[HisseO]

Originally Posted by davil

==========================================
the 40 unit has only one membrane so was easier to check one.
On inspection looked yellow on color (good) but when I touched started to peel off.
Not a scientific method BUT good enough for me.
Again, because you do not have any records the membrane remains the prime suspect in my view.
I think will be advisable to open the second membrane housing to check that membrane at least visually.
I scratched the surface with care and that is when just peeled off.

I have opened the 2nd housing and the membrane is in the same shape as the first one. Nothing crumbles when I gently try to scratch it.
You mentioned that after servicing the pump, you had the exact same issue as me:
It was not producing any water when using sea water source and eventually producing water when using tap water source? Correct?

[HisseO]

Here is a picture of the 2x membranes.
There are traces of oxydation on the side where water is feeding the housing, probably a bad signe, but the membrane itself doesn't show any oxydation.

[davil]

Originally Posted by HisseO

Here is a picture of the 2x membranes.
There are traces of oxydation on the side where water is feeding the housing, probably a bad signe, but the membrane itself doesn't show any oxydation.
Attachment 235713

===============================================
tough call
visually my membrane looked better (uniform yellow and shiny)
and yet was no good
intriguing that tap water will go thru and sea water will not.
hate to be in your shoes as the cost of the membranes is so high but cannot think of any ways to call it.
have you try to run your fingernails so gentle?