Click for Lurssen Click for JetForums Click for Nordhavn Click for Westport Click for Nordhavn

watermaker pre filters

Discussion in 'Watermakers' started by ArielM, Sep 6, 2011.

You need to be registered and signed in to view this content.
  1. ArielM

    ArielM Senior Member

    Joined:
    Jul 8, 2010
    Messages:
    179
    Location:
    Los Angeles
    I have a sea recovery water maker with a pre filter and oil water separator. What is the technical difference between the two filters? The oil water separator looks JUST like the pre filter except it has a sock over it. Are there any other differences? I assume the sock is the oil absorbing agent so in theory shouldn't i be able to use two oil/water separators as opposed to one of each filter?

    I could be really off on this so please let me know what you think.
  2. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    13,980
    Location:
    Fort Lauderdale
    The ordinary filter takes out debris before hitting the oil/water seperator so that the oil/water seperator doesn't get clogged with debris quickly. I beleive the oil/water seperator is a finer filtering medium and would clog too quickly without the pre-filter in front of it.
  3. madkaw

    madkaw New Member

    Joined:
    May 29, 2009
    Messages:
    2
    Location:
    Ft. Lauderdale, FL.
    The oil/watater seperator is plumbed opposite to the pre-filter, water enters from the center and exits to the outside. Need to connect input hose to the outlet.
  4. ArielM

    ArielM Senior Member

    Joined:
    Jul 8, 2010
    Messages:
    179
    Location:
    Los Angeles
    If that was the case then why does the oil/water separator have the sock on the outside? i thought the sock was an oil absorbing agent?
  5. Capt Bill11

    Capt Bill11 Senior Member

    Joined:
    Feb 27, 2006
    Messages:
    1,450
    Location:
    Sarasota/Ft. Lauderdale FL

    Have you asked Sea Recovery?
  6. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    13,980
    Location:
    Fort Lauderdale
    I have always seen them plumbed in series, first to the pre-filter to capture large debris and then to the oil water seperator, and yes the sock is an oil absorber. So the water runs into the prefilter, then out to the oil water seperator, through that and then on to the membranes.
  7. Pascal

    Pascal Senior Member

    Joined:
    Feb 29, 2008
    Messages:
    6,706
    Location:
    Miami, FL
    You should have 2 prefilter, first a 25 micron then a 5 micron

    I dint recall where the oil separator should be since we don't have one on the boat i run. Check the manual it s in there (I m not on the boat so invent check)

    If the cartridge inside the sock is a pre filter you need to know how many micron it is
  8. Capt Bill11

    Capt Bill11 Senior Member

    Joined:
    Feb 27, 2006
    Messages:
    1,450
    Location:
    Sarasota/Ft. Lauderdale FL
    He may be talking about the large Sea Recovery filter/separator units. If that is the case you have a large "junk" filter and then a large oil/water separator. It's different than some other setups where you have 2 small prefilters and than an oil/water separator.

    Lower left corner.

    cs_modular_dimen.gif
  9. ArielM

    ArielM Senior Member

    Joined:
    Jul 8, 2010
    Messages:
    179
    Location:
    Los Angeles
    Ya i have the commercial pre filter and then the oil/water separator. Capt J is also right in that it is in series.

    now i have a few oil water separators and no pre filters (spares). I dont see why i can't use this oil water separator filter in BOTH the pre filter canister and the oil/water separator. now from a financial standpoint i can understand the pre filter is cheaper and it wouldnt make sense to do what i am saying but since i already have 4 of these oil/water separators i dont see any technical reason not to.

    Commercial pre filter is 5 micron not sure about oil/water separator.
  10. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    13,980
    Location:
    Fort Lauderdale
    Because using an oil/water seperator without a pre-filter, the oil water seperator will quickly clog with debris. Also the debris may stop the oil/water filter from filtering the oil. A lot of times you can usually find the pre-filters at your local hardware store in the water department in both 25 and 5 micron unless yours is a larger one.
  11. Capt Bill11

    Capt Bill11 Senior Member

    Joined:
    Feb 27, 2006
    Messages:
    1,450
    Location:
    Sarasota/Ft. Lauderdale FL
    Are you somewhere where you can't get the filters sent to you? Or you need them right away? Because you could wash out the pre-filter in a pinch and get some more life out of it.

    Otherwise just order some new pre-filters.
  12. Pascal

    Pascal Senior Member

    Joined:
    Feb 29, 2008
    Messages:
    6,706
    Location:
    Miami, FL
    It also depends on wherE you are. I don't know how the water is out on the left coast but in new England for instance we need a 50 micron plankton filter (washable SS element ) which needs cleaning every 5 to 7 hours. The smaller 5 and 25 pre filters also needs to be replaces at the same time

    Yes the 5 and 25 can be cleaned but I don't find that they last as long after that

    In the bahamas, i take out the plankton element and we get 25 hours or more from the pre filters

    We had no room in the ER for the commercial size filters unfortunately

    I m surprised that you only have 5 mic prefilter but maybe on the left coast you don't need the 25...

    Btw a good source for the charcoal and PH filters is filterfast.com MUCH cheaper than sea recovery and identical brand. Unfortunately they don't have the pre filters
  13. ArielM

    ArielM Senior Member

    Joined:
    Jul 8, 2010
    Messages:
    179
    Location:
    Los Angeles
    great site but i dont think they have the commercial pre filter. sea recovery charged 5x more then these filters are worth simply because they make off sizes.

    Do you know a good place to buy the membranes when the time comes? I have the aqua series 600gpd. I was told that i mine is a standard 2.5'' and that there are a few other companies that will work with mine.

    i had heard from a dealer that SR changed the size of the membranes on their newer units so you have to buy their membranes.
  14. Capt Bill11

    Capt Bill11 Senior Member

    Joined:
    Feb 27, 2006
    Messages:
    1,450
    Location:
    Sarasota/Ft. Lauderdale FL
    They don't last long after you clean them. But if you are in the middle of no where and short on filters it's better than nothing.

    Go to http://www.waterfilters.net and get the spun poly filters they have a much larger surface area so they last a long time.