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Gravity deli case

Discussion in 'Refrigeration' started by MOFO the psychic gorilla, Sep 18, 2017.

  1. MOFO the psychic gorilla

    MOFO the psychic gorilla sitting on two achers

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    Got one where the guy sees any ice on the coil sends him into a panic. Is there a way to make temp on a gravity coil without ice forming and long off cycle defrosts? No hot gas just off cycle on this one.
     
    mike1020 likes this.
  2. crackertech

    crackertech assholiness *

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    nope
     
  3. MOFO the psychic gorilla

    MOFO the psychic gorilla sitting on two achers

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    Thanks

    Do these (not self contained) usually have some kind of gas defrost?
     
  4. crackertech

    crackertech assholiness *

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    Most use hot gas or cool gas defrost
     
  5. knave

    knave Undeterred

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    We recently had this issue. Bottom evaps had fans but the top static coil would freeze up. (After we replaced it.)

    We added an EPR at the rack to set the coil temp. (It had been running colder than needed at rack pressure)
    Also it had a suction stop for backup temp control and defrost.

    Then they still had trouble, ended up with 1 defrost per day at 2:00 am, for about 90 minutes of offtime. And that did the trick eh.
     
    Last edited: Sep 18, 2017
  6. frozensolid

    frozensolid Psychologist's Dream

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    Buy him an ice pick. :) Seems to be the tool of choice for customers everywhere.
     
  7. 404eh

    404eh New Member

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    It's our fault there's ice though..
     
  8. Jon

    Jon Team Canada

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    If they unload case at night install a switch that shuts off a liquid line solenoid or suction stop and they can power it off at night to defrost and turn on in morning when loading case . If not make sure like knave said you need 1 long defrost 90 minutes is typical
     
  9. Zman

    Zman Hanging by a Thread

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    90 minutes doesn't destroy Product? And what's a suction stop,is it like a solenoid? Works off temp or pressure? Just curious!
     
  10. crackertech

    crackertech assholiness *

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    This
     

    Attached Files:

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  11. Zman

    Zman Hanging by a Thread

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    Just never heard it referred to as a suction stop. But I guess that's a good definition.
     
  12. knave

    knave Undeterred

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    For most of that time cold air is falling off the melting ice. The product won't warm up that fast in a closed case.

    A suction stop solenoid is just like a liquid line solenoid but on the suction line. it allows the evaporater pressure to go up as the case warms.

    The SORIT valve that cracker posted also regulates the evap pressure (and thus the evaporating temperature) during refrigeration.
     
    Zman likes this.
  13. Zman

    Zman Hanging by a Thread

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    Now whats a Discharge Stop? :D
     
  14. knave

    knave Undeterred

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    :eek::eek::eek:
    I had to clean a bunch of them out of a sewage ejector pit a few months ago. :chairshot:
     
    LemonWizard likes this.
  15. coldsnap

    coldsnap -20 on the money

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    Air temp and product temp are two different things. I tell customers that when they see units in defrost, especially freezers. We have some old homemade wooden cooler boxes that get 70 or 90 minute defrosts at 2 am. You just have to make sure the defrost clock is at the right time.
     
  16. MOFO the psychic gorilla

    MOFO the psychic gorilla sitting on two achers

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    This is one case that is two sections screwed together.
    Each section has a tstat and liquid line solinoid.

    There is one remote c/u with a defrost timer that looks like it kills power to the c/u. Someone added a accumulator.

    Looks like someone installed it as if it was a typical remote piped cooler. (Pipe job is nasty)

    It's a new customer and cause I fixed one thing he's got me looking at everything he's been fighting to keep working for years with the last guy.

    On this one he was fighting leaks, uneven cooling and freeze ups on this deli case so for starters on the cheep I put in digital stats replacing the mechanical just for ease of fine tuning temp with what they had to work with and replaced the hacked over and over flare txvs to sweat valves.

    From where it started from the box is colder than it ever was and ice is light imo for this high use/ air leaky case.

    Defrost was set for 45 min 6 pm 12 am 6 am

    Haven't been back to see the ice but need to get back cause the ac was hacked too and ran out of time.

    One of the complaints about the ice is when it was in defrost the ice would plop off the coil and sometimes hang over the drip pan slightly which would cause a drip down into the case.

    The unit had a 12pm defrost setting I suggested removing so at least when it was in defrost they would be closed and the food would be covered.
     
  17. LemonWizard

    LemonWizard Blinky Lights Wizard

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    What is the humidity in the building? Your only option may be to lower that to slow the formation of ice.
     
  18. MOFO the psychic gorilla

    MOFO the psychic gorilla sitting on two achers

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    Good point. I am headed back to fix the AC :popcorn:

    Wasn't something I noticed being a issue though.
     
  19. heavyevans

    heavyevans FNG

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    If you're new to these type of cases. Take a peek under the panels the product is resting on.
     
  20. MOFO the psychic gorilla

    MOFO the psychic gorilla sitting on two achers

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    This one is a open bottom with short solid doors and a second gravity coil on the back wall.