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Thread: carrier issue

  1. #1
    Join Date
    Sep 2010
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    miami,fl.
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    677

    Confused carrier issue

    carrier A/h m#40rm-012--b611hc s#4806u30804 carrier condenser M#38ard012--k501--
    S#1007g40124
    one tech went and found stage one frozen evap. disconnected 1st stage and i returnedthe following day to check the operation. found evap coil dirty, also txv for circuit# 1 had been replaced carrier txv part #ea03xc376 and they left the sensing bulb hanging in the air not connected to the suction line. it was about 67 degrees outside around the condenser all pressures were low so i set up for an evap coil cleaning then will check tvx. we cleaned the evap coil really good can shine a light through and see the light, installed sensing bulb onto the suction line, both bulbs are installed and insulated at 8 oclock 1-1/8 suction line. found a damper in the return duct was closed opened damper. checked amps on blower motor rated at 5.6 amps im pulling 4.9 and 5.2 on my high leg. so im pretty much maxed out. now my pressures circuit #1 low 52 psig= 27 degrees with suction line temp at king valve 47 degrees= 20 degrees SH 210psig=104 degrees liquid line 80 degrees=24 deg. SC
    circuit #2 55 low psig=30 degrees, line temp59 degrees,= 29 deg SH hi side 190 psig =98 degrees liquid line 80 degrees,= 18deg. SC both sight glasses are clear, according to the charging chart i need to remove gas on both circuits im getting 17 degree split across evap coil. ambient around cond. unit was about 73 degrees thats a rough guess. please any input is appreciated i have a feeling ill be going back.

  2. #2
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    Jul 2009
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    Columbia, MD
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    low load or lack of airflow.

  3. #3
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    Jan 2008
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    Dallas ,Texas
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    Are the TXV's Danfoss?

  4. #4
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    May 2002
    Location
    evansville indiana
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    943
    +1

    Waits and subscribes.....
    mikeacman

  5. #5
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    Sep 2010
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    Quote Originally Posted by Dallas Duster View Post
    Are the TXV's Danfoss?
    The original one on stage #2 is still a danfoss, the txv for stage one looks like a sporlan valve but just has a carrier part# on it. But I'm sure it is.

  6. #6
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    May 2002
    Location
    evansville indiana
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    943
    What is your return air temperature . Wet and dry bulb if possible .

    What is your supply temperature.



    .
    mikeacman

  7. #7
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    Sep 2010
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    miami,fl.
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    Quote Originally Posted by gravity View Post
    low load or lack of airflow.
    On the lack of airflow it's moving max the blower motor is designed to do. If the duct work was to small it wouldn't max out on amperage. My return air was 68degrees but even with 74 degrees return air my back pressure was only 3 psig higher. I appreciate the feed back, because I'm lost. :|

  8. #8
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    Sep 2010
    Location
    miami,fl.
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    .

    Quote Originally Posted by mikeacman View Post
    What is your return air temperature . Wet and dry bulb if possible .

    My return air temp 67 degrees and 50 degrees supply air. Temps were taken at the inlet of a/h return and right at the supply plenum


    .

    .[/QUOTE]

  9. #9
    Join Date
    Jan 2008
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    I think there was a capacity problem with the Danfoss valve. Is there a motor master for head pressure control? The head pressure is a bit low and compound a 68 degree return air it ain't helping it. What does the duct look like ? Get with rundawg and get his TESP instructions and perform a test.


    Quote Originally Posted by anthonyac1 View Post
    The original one on stage #2 is still a danfoss, the txv for stage one looks like a sporlan valve but just has a carrier part# on it. But I'm sure it is.

  10. #10
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    Sep 2010
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    miami,fl.
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    Quote Originally Posted by Dallas Duster View Post
    I think there was a capacity problem with the Danfoss valve. Is there a motor master for head pressure control? The head pressure is a bit low and compound a 68 degree return air it ain't helping it. What does the duct look like ? Get with rundawg and get his TESP instructions and perform a test.
    no motor master on neither fan this condenser has 2 fans one for each circuit with like a sheet metal wall dividing the two basically if i shut down one fan motor that circuit will shut off on head pressure.

  11. #11
    Join Date
    Jul 2009
    Location
    Columbia, MD
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    you check airflow by amp draw?

    cant say i've ever done that before.

    i would use the IOM and check your airflow by their methods.

    usually by rpm, you may find your answer with static pressure.

  12. #12
    Join Date
    May 2012
    Posts
    27
    is the return grill clean and has nothing blocking it? check the blower wheel and housing if its caked w crud

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