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  1. #1
    Join Date
    Sep 2014
    Location
    Austin, TX
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    277
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    Contaminated System

    We were not as thorough as we should have been, but it was after the fact that the customer told us that he had run water or some other fluids through the refrigeration circuit of the 10-ton shell in tube evaporator that he insisted we use, as opposed to purchasing the new kit I suggested (15HP condensing unit).

    we installed a replaceable core drier can for clean up, and we have changed the oil in the compressor a couple of times. We having been drawing a vacuum on the evaporator and changing the oil in the vacuum pump for days. We finally got the micron gauge to hold below 1k with the entire system connected and started it back up late on this Friday.

    What can we expect from this? Currently the moisture indicator is still YELLOW.

  2. #2
    Join Date
    Sep 2013
    Location
    Atlanta, GA
    Posts
    245
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    I once installed a rack system that a place got cheap because it was involved in a truck accident and had been exposed to the elements via a couple broken copper stubs. We had a vacuum on it for months before even installing it. Changed the driers several times during the vacuum after installation, but by the time we started it up the moisture indicator was green. Remember that the driers are meant for the final moisture removal as they don't really hold much water in terms of drops of water that you could see. You have a lot of work still to do.

  3. #3
    Join Date
    Sep 2014
    Location
    Austin, TX
    Posts
    277
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    I am wondering if I should pull the entire charge then, and just suck on the entire system as you describe. We had pumped the refrigerant charge down and concentrated on crankcase and evaporator with them isolated.

    should we put a new core in the drier when we do that? Will the drier be effective while just pulling a vacuum?

  4. #4
    Join Date
    Sep 2013
    Location
    Atlanta, GA
    Posts
    245
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    is it working? if it is I would continue replacing the oil and driers, if it is experiencing moisture issues I would reclaim the refrigerant and drain the oil and do a nitrogen sweep followed by multi day vacuum then put in new oil, driers and refrigerant

  5. #5
    Join Date
    Sep 2014
    Location
    Austin, TX
    Posts
    277
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    The moisture indicator was still yellow, Friday. We will be back on it this week.

  6. #6
    Join Date
    Sep 2002
    Location
    Virginia
    Posts
    3,432
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    Assuming the indicator is working right...

  7. #7
    Join Date
    Sep 2014
    Location
    Austin, TX
    Posts
    277
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    It was green when we started - brand new 15HP Trenton condensing unit.

  8. #8
    Join Date
    Mar 2013
    Location
    NJ
    Posts
    68
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    On water contaminated supermarket rack I have found changing oil and driers once the system is running to be very effective, often several times in a 24 hr period. Most often they were 22 or 12 systems that had to be kept running because store was open. Often the charge was new because a water cooled condenser failed, but not always. If an install went bad, we would try to save the charge. Acid test once you think its dry.

  9. #9
    Join Date
    Sep 2014
    Location
    Austin, TX
    Posts
    277
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    It has been suggested that the refrigerant that was in the system and exposed to the contamination be disposed of.

  10. #10
    Join Date
    Aug 2002
    Location
    Southold.calm
    Posts
    6,802
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    If the pump oil gets contaminated quickly you need a Freeze Trap before the pump.
    It will save your pump


    http://www.amazon.com/Ice-Nitrogen-v.../dp/B00LZESIPO

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