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  1. #1
    Join Date
    Aug 2018
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    Settle an augument

    I work for a small shop. Currently only two of us doing HVAC work. My boss says to charge ALL units to 20 degrees SH. I say no if it has a txv on it you charge to what he manufacture says for SC. He says no that if the house temp is high SH will be high. I say charging a TXV installed unit by setting SH will cause the unit to be undercharged. Am I correct?

  2. #2
    Join Date
    Feb 2017
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    New York
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    Subcooling will be low and superheat will be high with a high load. That is called pull down. Numbers are not accurate. The house needs to be close to setpoint to get accurate numbers to finalize charge. And yes, with a TXV you charge by subcooling. Most condensing units that I know of have a target number.
    -----Stop, step back, relax and have another go at it.-----

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  4. #3
    Join Date
    Jul 2005
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    Quote Originally Posted by rickinva804 View Post
    I work for a small shop. Currently only two of us doing HVAC work. My boss says to charge ALL units to 20 degrees SH. I say no if it has a txv on it you charge to what he manufacture says for SC. He says no that if the house temp is high SH will be high. I say charging a TXV installed unit by setting SH will cause the unit to be undercharged. Am I correct?
    Ask him if he's ever read an installation guide.

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  6. #4
    Join Date
    Dec 2007
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    Quote Originally Posted by hvacrmedic View Post
    Ask him if he's ever read an installation guide.
    Why not beer can cold?
    The Food Stamp Program, administered by the U.S. Department of Agriculture, is proud to be distributing the greatest amount of free meals and stamps EVER.
    Meanwhile, the National Park Service, administered by the U.S. Department of the Interior, asks us to "Please Do Not Feed the Animals". Their stated reason for this policy "... the animals become dependent on handouts and will not learn to take care of themselves."
    from an excerpt by Paul Jacob in Sun City, AZ

  7. #5
    Join Date
    Sep 2002
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    Because maybe he's English.

    PHM
    ----------


    Quote Originally Posted by pacnw View Post
    Why not beer can cold?
    PHM
    --------
    The conventional view serves to protect us from the painful job of thinking.

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  9. #6
    Join Date
    Jan 2007
    Location
    Mn the state where absolutey nothing is allowed
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    Quote Originally Posted by Poodle Head Mikey View Post
    Because maybe he's English.

    PHM
    ----------
    that may work well.....

    43 degree coil, 12 degree SH, yeah 55 degrees is about what english stout should be served at
    my boss thinks its possible to repeal the laws of physics

  10. #7
    Join Date
    Mar 2015
    Location
    Medford, N.Y.
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    Maybe because he mixed up some info. Copeland says that they want a minimum of 20*SH at the comp.

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