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My Rix SA-6 Diesel

Discussion in 'Compressors, Boosters & Blending Systems' started by rob.mwpropane, Nov 11, 2020.

  1. rob.mwpropane

    rob.mwpropane Contributor

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    Good day all. I recently for better or worse bought a Rix and am just starting to have the funds for the different fittings that I didn't know I needed after buying a filter tower (that I didn't really know I needed:)

    So obviously, not having any experience and buying stuff that I didn't really know about may not have been the wisest move but I'm here now. NOT having to drive 3 hours (45 min up and back x 2) to drop / pickup tanks will make it worth it in the end (I hope:))

    I chose this compressor as it was a newer model and looked in great shape. It's also oiless, so one less thing to have to worry about. It's ran from a Yenmar diesel engine which is great for me as we have diesel at the shop for days, plus it doesn't get sticky or turn like gasoline does. Maybe one day I'll convert to electric, but for now this is what I have.

    I'm starting to build a parts list and I think I've pretty much got it figured out, but I could use some pointers. I know I need a back pressure valve, but should I include 2 if there is a quick disconnect between the compressor and the filter tower?

    As you can see in the picture, I would remove the check valve and place that on the inlet of the filter tower and replace it with a BPV, and have another BPV after the filter tower. This way I can disconnect the tower and still keep it and the towers that came with the Rix under pressure and move the compressor. Any thoughts?

    My compressor came in a nice little box which it will probably stay in most of the time unless in use. I do not have a designated place in the shop to put it just yet.
     

    Attached Files:

  2. rob.mwpropane

    rob.mwpropane Contributor

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    Here is my other thread with more pictures, but I figured it would be easiest to start fresh.

    Filter Tower Question
     
  3. tbone1004

    tbone1004 Technical Instructor ScubaBoard Supporter

    # of Dives: I'm a Fish!
    Location: Greenville, South Carolina, United States
    18,663
    11,125
    that check valve may actually be a non adjustable PMV

    If you go that route, you will need a check valve on the inlet side of the tower as well as a PMV after the tower.
     
    NAM001 likes this.
  4. rob.mwpropane

    rob.mwpropane Contributor

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    Great...how would I tell what it is? IF this was a regular check valve my plan was to exchange it for a PMV and place it on the inlet of the external filter tower. Then add another PMV after the external filter tower.

    Does that make sense?
     
  5. rob.mwpropane

    rob.mwpropane Contributor

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    Here's another pic. I'll have to go later and see if it has any #'s on it.

    Is there any flaw with having PMV after the colecers, then quick disconnect, check valve, filter tower, then another PMV? The ones from August come pre set at 1800 psi, which I think is good. I guess the whole point is allowing the 3rd stage to build pressure right away and hold pressure even if the quick disconnect is undone. Thoughts?
     

    Attached Files:

  6. tbone1004

    tbone1004 Technical Instructor ScubaBoard Supporter

    # of Dives: I'm a Fish!
    Location: Greenville, South Carolina, United States
    18,663
    11,125
    The pic you send is of the OPV on the top which doesn't say anything. Look for part numbers or markings on the other brass bit.

    If it is a PMV, then leave it where it is, you need a PMV after the coalescers for them to actually do their job as well as seat the third stage so it doesn't hammer so leave it where it is. You want a check valve on the inlet side of the filter towers for disconnecting them.

    plumbing should be
    On pump
    coalescer
    PMV
    quick disconnect
    On filter
    QD with bleed valve
    hose
    check valve
    filters
    PMV
    hose
     
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  7. rob.mwpropane

    rob.mwpropane Contributor

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    The OPV is set to 3300 psi and sits on top of what I'm assuming is a check valve. All the pictures that I have seen I haven't seen a PMV that looks like that, but I understand that I know absolutely nothing (which is why I'm posting).

    Yes, everything else that you posted is exactly how I planned to do it. I guess my main question was "should I have a PMV after the coalescers and before the quick disconnect"....but if that is a PMV and not a check valve then I'm good.

    If that's "just" a check valve, then I'll move it to the inlet of the filter tower and replace it with a PMV. (and still have a 2nd after the tower of course).

    ****(On another note, to set the OPV higher I would install a gauge into the "T" to the left of the coalescers in the 1st pic of this thread, and use an allen wrench to tighten until it bled at the desired pressure? I was thinking take it to 4K...)
     
  8. tbone1004

    tbone1004 Technical Instructor ScubaBoard Supporter

    # of Dives: I'm a Fish!
    Location: Greenville, South Carolina, United States
    18,663
    11,125
    yes, you need the PMV because it will help accelerate seating of the 3rd valve piston. You could technically do the same thing with a ball valve if you never intend to run it without the filter towers, but I would rather spend the money on a PMV where you don't have to think about it.

    Set that OPV around 4500psi or so IMO. You want it a few hundred psi over what you intend to fill to.
     
    rob.mwpropane likes this.
  9. rob.mwpropane

    rob.mwpropane Contributor

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    That's the plan. Thanks...
     
  10. rob.mwpropane

    rob.mwpropane Contributor

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    Does a PMV also act as a check valve? For instance, if I have a PMV after the filter tower and then a gauge, the gauge should only be reading the pressure after the PMV correct? Even if the pressure exceeds what the PMV is set at?

    I know this is a silly question...but I can't can't find the silly answer.
     

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