freezer/refrigerator
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  1. #1
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    May 2008
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    freezer/refrigerator

    Servolift, Model RF-11M, sSerial #09/03232985-1, R404A
    independent systems.

    Cabinet temp 0deg

    freezer side suction line freezing up.
    suction pressure 18lb. suction line temp ranging from 31deg to -14deg.
    8deg DT across the condencer.

    Is this large range of suction line temp a sight of a low charge and that's what's causing the suction line to freeze up?

    I did do a leak check and found nothing.
    I used a little PFM to fix it.

  2. #2
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    What's the issue here? Not keeping up? Look at the pt chart for 404, at that pressure anything uninsulated is going to freeze? Looks like your superheat is swinging. Bulb insulated?

  3. #3
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    Quote Originally Posted by ryan1088 View Post
    What's the issue here? Not keeping up? Look at the pt chart for 404, at that pressure anything uninsulated is going to freeze? Looks like your superheat is swinging. Bulb insulated?
    It's the insulated line thats freezing, The bulb is covered.
    I used a little PFM to fix it.

  4. #4
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    There is no problem cooling the box, just ice on the insulation?

  5. #5
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    Feb 2006
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    Better insulate it lol

  6. #6
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    Quote Originally Posted by ryan1088 View Post
    There is no problem cooling the box, just ice on the insulation?
    yup
    I used a little PFM to fix it.

  7. #7
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    Time for some thicker insulation. I use 1" thick and usually don't have that problem aside from a few seams.

  8. #8
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    Quote Originally Posted by ryan1088 View Post
    Time for some thicker insulation. I use 1" thick and usually don't have that problem aside from a few seams.
    so that big suction line temp swing is ok?
    I used a little PFM to fix it.

  9. #9
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    Sight glass clear? Temp probe insulated? Single evap or multiple evap system? Are you measuring this at the condenser or inside the freezer?

  10. #10
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    Quote Originally Posted by ryan1088 View Post
    Sight glass clear? Temp probe insulated? Single evap or multiple evap system? Are you measuring this at the condenser or inside the freezer?
    sight glass is clear, measure at the low side service, it's a chest style freezer. temp probe is insulated.
    I used a little PFM to fix it.

  11. #11
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    Any driers ahead of the txv? Between sight glass and txv? Suction driers? And yes I'd not be feeling great about the superheat bouncing all over the place like that.
    Last edited by ryan1088; 06-09-2012 at 11:56 AM. Reason: Additional Thought

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