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  1. #1
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    Superheat and Subcool on package units.

    How do you guys get a proper measurement when you only have two H and L ports and the lines are inside the system. do you just recover and charge by weight??? I don't see any other alternative.

  2. #2
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    Dec 2003
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    Citrus County, Florida
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    That is the most accurate method. Some units do provide pressures related to temps. Just remember there is no real line lengths so you have to be careful of superheat.
    Doug

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  4. #3
    Join Date
    May 2017
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    I always charge by weight according to unit tag for package units can't go wrong

    Sent from my SM-N950U using Tapatalk

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  6. #4
    Join Date
    Dec 2014
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    midwest
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    Youll find on microchannel units that you may have to reduce the charge below factory spec because of head pressure trips.

    Sent from my SM-G930V using Tapatalk

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  8. #5
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    Jun 2011
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    NE Ohio
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    Quote Originally Posted by OGlad View Post
    How do you guys get a proper measurement when you only have two H and L ports and the lines are inside the system. do you just recover and charge by weight??? I don't see any other alternative.
    remove a side panel and attach a temperature probe to either the liquid or suction line ?

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  10. #6
    Join Date
    Sep 2002
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    I'm not sure what your question is - why can't you use the standard pressures and temperatures to calculate SH and SC ? Just put the panel in place as well as you can - it's not like the units are anything like airtight to start with. <g>

    PHM
    -------


    Quote Originally Posted by OGlad View Post
    How do you guys get a proper measurement when you only have two H and L ports and the lines are inside the system. do you just recover and charge by weight??? I don't see any other alternative.
    PHM
    --------
    The conventional view serves to protect us from the painful job of thinking.

  11. #7
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    NE Ohio
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    Quote Originally Posted by Poodle Head Mikey View Post
    I'm not sure what your question is - why can't you use the standard pressures and temperatures to calculate SH and SC ? Just put the panel in place as well as you can - it's not like the units are anything like airtight to start with. <g>

    PHM
    -------

    there is also a bit of a process involved to make sure you are not introducing moisture to the system when you recover and recharge, not that you cant get everything below 200 microns .... seems much simpler just to check the SH or SC ....

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  13. #8
    Join Date
    Feb 2006
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    Phoenix,AZ
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    Quote Originally Posted by OGlad View Post
    How do you guys get a proper measurement when you only have two H and L ports and the lines are inside the system. do you just recover and charge by weight??? I don't see any other alternative.
    I use a wireless clamp thermometer. And peek into the unit as it's running to get the line temps.

  14. #9
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    Nov 2006
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    Southeastern Pa
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    I'm not sure what you're trying to ask....are you trying to charge the unit, or are you doing a maintenance inspection?
    [Avatar photo from a Florida training accident. Everyone walked away.]
    2 Tim 3:16-17

    RSES CMS, HVAC Electrical Specialist
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  15. #10
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    May 2018
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    San Fernando Valley, CA
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    Thread Starter
    It's just kind of annoying, on the newer lennox package units, its hard to get to the L and H side line set. To recharge is a pain in the ass.

  16. #11
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    Nov 2006
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    Southeastern Pa
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    Okay....just so we're on the same page.....what model Lennox package unit are we talking about?
    [Avatar photo from a Florida training accident. Everyone walked away.]
    2 Tim 3:16-17

    RSES CMS, HVAC Electrical Specialist
    Member, IAEI

    AOP Forum Rules:







  17. #12
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    May 2018
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    Thread Starter
    I don’t have the model. It’s one of my clients that I changed a cap for a few months ago. I didn’t really touch refrigerant because the unit was new and the line set was hard to get to. Next time I’m there for service, I’ll remove the panel I suppose. I doubt she has leaks yet.

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  19. #13
    Join Date
    Apr 2018
    Location
    Rhode Island
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    If it's a regular account ,drill two holes but enough for gauges!

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