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  1. #1
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    Jan 2015
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    Help resolve a difference of profession opinion (journeyman I'll bet....)

    The condition is on the oil system for a chiller, but the question can be applied across the refrigeration / HVAC spectrum. There is an oil leak of one drop every 30 seconds from an oil sump flange cover that is under the oil level. The oil sump is at 250 psi @ 130F. You can see bubbles (foaming) around the bolt heads, runs down the flange, then drips into a coffee can. The bolts are tight at about 15 ft pounds of torque. The discussion that has gotten several peoples "shorts in knot" is how much refrigerant (R22) is entrained in the oil or how much refrigerant is leaking as well. One side is saying zero refrigerant and maybe a pint of oil in 24 hours. The other extreme is not disagreeing with the amount of oil but saying there is a significant amount of refrigerant being lost

    Just in case you're asking the leak did not start until the sump reached 225 psi, The machine held a 500 micron evacuation for an hour. Passed a 225 psi nitrogen pressure test (pressure test at 65F). We will secure the chiller and fix the leak later today.

    So for the experts out there how much refrigerant do you think is contained in the oil. (There's a case of beer ridding on this)

    Thanks to any who care to help

  2. #2
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    Thread Starter
    forgot; The cover is only about 5 inches in diameter and the bolts are 5/16 -18

  3. #3
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    There's probably very little if any at all. Oil & Refrigerant generally do not mix if there was any "Liquid" refrigerant coming out it would boil off long before you'd see it.

    Let the debate begin

  4. #4
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    I agree, I wouldn't think there is much in the oil itself. That said, if the oil level drops below the leak, there will be vapor.

  5. #5
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    Quote Originally Posted by Answer-Man View Post
    The oil sump is at 250 psi @ 130F. :
    A little high?

  6. #6
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    Quote Originally Posted by The_Sale View Post
    I agree, I wouldn't think there is much in the oil itself. That said, if the oil level drops below the leak, there will be vapor.
    My answer!!

  7. #7
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    May 2014
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    Australia
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    Can you check with electronic leak detector, as I believe refrigerant will leak out with oil.
    Won't be much, but refrigerant will come out.
    If you drain oil out while system under pressure, oil foams, which means refrigerant as well.

  8. #8
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    Jun 2014
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    I just leak checked a rack today, had an oil float sight glass with a drip on the bottom of it, 0ppm with a bacharach PGM-IR. Only had an O ring in it. Put a quad ring in it too, no more drip.

    Sent from my SM-G920T using Tapatalk

  9. #9
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    Thread Starter
    Update Using a Bacarach 19-8106 the leak barely made it light up on the normal sensitivity so somewhere around 0.25 oz per year per the bacarach information concerning sensitivity

    Thanks to all

  10. #10
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    Mar 2015
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    Medford, N.Y.
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    What brand chiller?Comp?Is 250psi normal for the oil sump? Copeland wants 300 "lbs or 400"lbs or 550"lbs for their "Bottom Plate", with a 5/16-18 bolt,depending on which comp is used. 15'lbs is 180"lbs.I say very very little freon would leak out.

  11. #11
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    Feb 2004
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    I went to a Carrier class back in the early 90's. There we were given with other stuff a chart on how much refrigerant the oil can en-train. I wish I still had the chart but it was a lot, so much so I won't write what I remember as some wouldn't believe it.
    We all know what happens when liquid refrigerant floods back to the sump and is entrained and how long it takes to move it into the system.
    Along with that, heat of the oil is a big factor. I was considering a static system with no CCH or one with flood back where the oil would be cold. It sounds like with the example given the oil is hot so most refrigerant should be in a vapor state. Another possible factor is how much of the flange is out of the oil and in the vapor sump area.
    Give me a relay with big enough contacts, and I'll run the world!

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  12. #12
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    Jan 2016
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    Fix the leak, liquid refrigerant can be present up to 70 degrees with r-22.

    Sent from my HTC6500LVW using Tapatalk

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