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  1. #1
    Join Date
    Jun 2003
    Location
    Lenexa, KS
    Posts
    435

    Confused Hygroscopicity of POE (and whether or not it should be replaced)

    Howdy folks,

    I've been given an opportunity to purchase some second-hand VRV equipment that I am very interested in installing in my home. The equipment is out of a small office building that houses the vendor of the equipment. They recently changed lines to a new VRF manufacturer, and so they are ripping out and selling all of their old equipment. It's in decent shape, not terribly old, and would permit me to replace an aging system in my home and also do some much needed zoning because the house has had an addition by the previous owner without accounting for the fact that the air conditioner would need to be upsized. The equipment is priced for what it would cost for me to buy a bare-bones system. Probably cheaper, actually.

    To my point: when this equipment was removed, they did not cap the refrigerant lines on the outdoor heat pump. This is a R-410A machine with POE oil. It has been sitting like this is steamy Kansas City for over a week. I am very concerned that the oil in this VERY expensive compressor is already ruined. Would you agree?

    I'm also of the impression that the only "fix" would be dump the oil out of the compressor and fill it with new, and that the entire system would need a pretty significant nitrogen purge and have a vacuum sit on it for a long, long time. Like days. My understanding of POE is that it simply isn't forgiving in this regard and that pulling a vacuum on it for a lengthy period of time still will not pull the moisture out of the compressor unless I do a complete oil change-out.

    Do you agree?

    For me, the uncapped lines are a deal-breaker, but I wanted a second opinion to see if I was blowing this out of proportion. I really don't want to turn down this high-dollar equipment, but I don't want to tear it apart and rebuild it just to make it work, either.

    Thoughts?
    "We are what we repeatedly do.
    Excellence, then, is not an act, but a habit."
    -Aristotle

  2. #2
    Join Date
    Jul 2007
    Location
    The Hot South
    Posts
    1,326
    Was the system pumped down and service valves closed?

  3. #3
    Join Date
    Mar 2007
    Location
    wedged in freezer shelf
    Posts
    6,800
    How about change the oil install a replaceable core drier, test the oil periodically and change driers till it is good to go. Could even pipe in some shut off valves on the drier.
    “If You Can Dodge A Wrench You Can Dodge A Ball”

  4. #4
    Join Date
    Sep 2008
    Location
    Western PA
    Posts
    25,721

  5. #5
    Join Date
    Aug 2004
    Location
    Kansas
    Posts
    133
    From one Ks reefer man to another
    I don't think I would want to sleep with wet POE problems even if they gave it away
    POE is plagued with problems even when it's dry and why are they changing brands?
    Was that mfg having major problems?
    Just my thoughts

  6. #6
    Join Date
    Jul 2000
    Location
    Guayaquil EC
    Posts
    10,392
    In my experience with POE exposed to moisture, there's really no need to change the oil. Just install a good filter-drier...ie, Sporlan...and in a short time it will pick up the moisture which has be adsorbed in the oil.

    I had an R404A remote condenser ice machine which had been disconnected and left wide open in storage for over a year (here in humid Florida). I had read some comments by RobY on the subject and decided to go ahead with just the filter-drier...and a moisture indicator. It was dry very quickly and has been running with no issues for several years now.

    I had another one shortly after that. It was a Copeland 2 HP low temp R404A condensing unit which had been installed and then returned to the wholesaler (because the tech couldn't get it to run right or some such reason. ). A few months later, I got it for a song and noticed it had been left open to the atmosphere. I then sold it to a restaurant for their walk-in. With just a new C163, it's run dry and happy ever since.

    Here's the thread:
    http://hvac-talk.com/vbb/showthread.php?t=140319

  7. #7
    Join Date
    Jun 2003
    Location
    Lenexa, KS
    Posts
    435
    Thanks for the replies.

    The reason why the equipment was removed was to make way for for the new brands that the vendor wanted to showcase. The units themselves were fully functional at the time of removal and completely salvaged.

    I don't know if the service valves were opened or closed.That didn't even occur to me. Guess I should check, huh?

    Are there any Daikin guys on here? Are filter/driers allowed on their system? I am under the impression that 3rd-party devices are highly restricted...

    Thanks.
    "We are what we repeatedly do.
    Excellence, then, is not an act, but a habit."
    -Aristotle

  8. #8
    Join Date
    May 2010
    Location
    Oxford, UK
    Posts
    338
    Some units use PVE oil, depends on make. Seem to remember fujitsu do.

    You can't vac the moisture out of POE as it chemically changes the oil, it kind of undoes the manufacturing process.

  9. #9
    Join Date
    Aug 2004
    Location
    Kansas
    Posts
    133
    When I started in this field my mentors used Kotex to absorb acid which came from a breakdown of refrigerants made from acid which made for an embarrasing
    trip to the grocery store but it worked. (Two cases of maxi-pads please)
    Now we have not only refrigerants made from acids but the new oils also are made from acids and alcohols which can change inside the system with the addition of water back into acid at high temperatures the same as the refrigerants. So we now get a double dose
    We could pull a vacuum for months or until the cows come home and not correct the situation if this has happened.
    Then we install driers and filters to remove the acid and water and then (we are told 5 years later) that the act of using some filter driers may have also removed the additives that were added to try to make POE work.
    What's next maybe an expensive field test kit to check for additives and mfg recommended additive kits to try to make POEs work in something other than jet engines?
    If you buy POE containing equipment that has been exposed expect anything
    as a couple driers and an oil change may not save your ax if you're paying the bills.

  10. #10
    Join Date
    Mar 2011
    Location
    East Coast FL
    Posts
    1,058
    Thoughts : if the service valves were closed, then obviously you'd be fine, if they were not...

    I have found offshore mini type equipment to be problematic, difficult to troubleshoot, finicky, non-robust, and don't lend themselves to overhaul, service, etc.

    I would go with a high seer split from Carrier or Lennox with a nice EWC zone system.

  11. #11
    Join Date
    Mar 2003
    Posts
    7,326
    have sold tons of daikin with little issue, for use in commercial settings. for me, i would dump the oil, refill, add a replaceable core drier and valves, and go to town. they dont give shietty compressors a seven year warranty.

  12. #12
    Join Date
    Sep 2010
    Location
    Western, MO
    Posts
    871
    If the price was right I would give it a go. Most of the stuff I have in my house was deemed unrepairable by other companies.

    I haven't looked at VRF systems much. I have a customer that might be interested in one. What new system is this place carrying and are they in the 435 & Lackman area group of suppliers?

    jim
    Common sense isn't very common anymore.

  13. #13
    Join Date
    Jun 2003
    Location
    Lenexa, KS
    Posts
    435
    Jim,

    Yes, they are in the 435/Lackman area of suppliers. They have an 8-ton 3-phase model available and various configurations of indoor equipment.

    I've got dibs on the 4-ton single phase until I tell them otherwise.

    Thanks for the replies, all. I will check service valves and see if they are shut. If not, I'm going to pass.
    "We are what we repeatedly do.
    Excellence, then, is not an act, but a habit."
    -Aristotle

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