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  1. #1
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    May 2007
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    Talking excessive superheat orifice help



    Hi Everyone

    Where superheat is excessive (despite adjusting TEV)
    can anyone tell me if it's worth going up an orifice size, say from 0-1?

    If not, why not?

    This particular job was designed by someone else and it's a bit of a one off.

    Thanks.



  2. #2
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    Aug 2006
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    Re: excessive superheat orifice help

    If on comissioning a system it apears the txv is underfeeding the evap, i don't see anything wrong with trying the next size up orifice.

    Does the system have a distributor after the txv? one system i got called in to look at for a friend had one that was set up horizontally with one capilliary above the other, in effect only the bottom cap saw any liquid and only half the evap did any work, we truned the distributor through 90' so both caps were side by side and the system worked as intended.

    Jon

  3. #3
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    Re: excessive superheat orifice help

    May require an externally equalized TXV, to compensate coil pressure loses.

  4. #4
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    Re: excessive superheat orifice help

    are you sure it is the TEV that is causing the malfunction? is the evaporator correctly calculated? are the lines the correct diam., and so on and on....and on....an...

  5. #5
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    Re: excessive superheat orifice help

    Thanks everyone

    I'm not sure now if the superheat is excessive, it's only a small fridge with quite a long run (10m) and i'm having to take my sat. pressure at the outdoor unit. Also I only took a couple of readings on the suction pipe and maybe didn't leave enough time for the valve to react blah blah blah

    but thanks anyway

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