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  1. #1
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    Typical liquid temperature for txv selection



    Hi,
    It sounds simple enough however when using a TXV selection program there are tipping points that change the valve and orifice size if inputting different liquid temperatures.
    So;
    I sometimes don't have the info at the time of production therefore for a supermarket rack with a heat exchanger just before the valve I will generally use 70°f (21°C) as my liquid temp for valve selection. Any thoughts?

    Thanks, Ken



  2. #2
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    Re: Typical liquid temperature for txv selection

    Ken,
    I would have thought you would be indicating amount of liquid line subcooling to make selection. Delta p across valve important & would have thought 2-5 deg C subcooling at inlet of TX valve.
    Saturated condensing pressure of 25 deg C seems low, so you would look at possible minimum & maximum ambient temperatures to help selection as well.
    Liquid/suction line heat exchanger would not guarantee amount of subcooling though.
    Have you any feedback on previous selections?
    Last edited by RANGER1; 15-11-2018 at 07:55 AM.

  3. #3
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    Re: Typical liquid temperature for txv selection

    Ranger 1, I've been selecting TXV's this way for many years without issue. However I'm working with a new installer who believes one of our selections should be larger which led to re-running the numbers research and this inquiry.

    Thanks for the feed back I'm sure more will be revealed.

    Ken

  4. #4
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    Brian_UK is offline Moderator I am starting to push the Mods: of RE Site Moderator : and general nice guy
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    Re: Typical liquid temperature for txv selection

    Sporlan documents 10-9 and 10-10 provide the correction factors to be applied to different liquid temperatures. Their baseline is 100°F.

    Download here http://sporlanonline.com/literature-...ansion-valves/
    Brian - Newton Abbot, Devon, UK
    Retired March 2015

  5. #5
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    Re: Typical liquid temperature for txv selection

    Ken,
    No worries, of course a number of ways to cross check things.
    After seeing Brians post I found this youtube link.
    We probably use Danfoss exclusively & they ask for different things than some others.

    https://www.youtube.com/watch?reload=9&v=LIFEQUUru4w

  6. #6
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    Re: Typical liquid temperature for txv selection

    Thank you Brian_UK, I use the Sporlan Product Selection Program. Great tool.

    Ken

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