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  1. #1
    Join Date
    Sep 2007
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    Somerset
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    63
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    Bad Day - Good day.



    Hi Guys!
    I had one of those days a couple of weeks ago.
    Where I was sent to do a "Look and Log!" Maintenance visit, on a site I rarely visit.
    Easy Day I thought!
    Logging a York Recip Chiller and a Carrier Screw Chiller.
    Met the customer (Happy with his plant!)
    Start logging the 2 recip (8 stages of Loading) York and immediately suspect an issue.
    As the 2 comps were running on 2 and 1 stage of loading both discharge limiting.
    Water temp at 12c setpoint at 9c. With an 8c split across the water cooled Condenser.
    shut 1 comp down to try and load the remaining up!
    Nightmare!
    Whatever I did I could not stop either overshooting and tripping on HP.
    17 bar unload and 18bar trip.

    I reluctantly called the customer down to the plant room and explained that his "Nicely Running Plant" was sick and that I was convinced his water circuit was blocked.
    The primary Pump Suction was approx. 10 psi. which was low according to the site Maintenance Engineer.
    On returning from checking and cleaning the strainers on his Evaporative Cooling Tower.
    He confirmed my suspicions were correct and showed me a handful of plastic bits!
    Smiling further,He then produced in the other hand a Mobile phone Battery!
    I kid you not!
    Apparently sat in the strainer was this plastic clad mobile battery.

    Well Pump Suction pressure now 20psi and split across condenser now 3/4c.
    A few more adjustments and the chiller was not only running balanced.
    But reaching set point and cycling off!

    The Carrier also had some Issues but that's another story!
    My day got better and We had a happy customer!

    Result!
    Grizzly


    Despite the High Cost of Living it still remains Popular!

  2. #2
    Join Date
    Feb 2009
    Location
    telford
    Posts
    1,926
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    25

    Re: Bad Day - Good day.

    Job creation comes to mind lol

  3. #3
    Join Date
    Dec 2007
    Location
    australia
    Posts
    2,475
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    Re: Bad Day - Good day.

    Grizzly,
    90% of techs probably not find what you did, would have accepted it was ok, not really wanting to find a problem.
    That's what makes you in the top 10%.
    Nothing is ever routine, unless you want it to be.

  4. #4
    Join Date
    Sep 2007
    Location
    Somerset
    Age
    63
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    Re: Bad Day - Good day.

    Ranger.
    Thank you for the complement my friend.
    I just thought it was an amusing story and one which some will remember for future reference.

    We all learn from those we work with and I count myself lucky to work with some of the guys I do!
    (Young and Old)
    I know from talking to you, that you are lucky to be able to occasionally impart your vast knowledge to younger colleagues.

    Sadly the days of there being two of you on a job are pretty rare over here Nowadays.
    Certain ammonia Jobs still necessitate 2 but even they are infrequent.

    But We Do have the Forum for those little Gems!


    Do you remember my story about the Vending Machine plastic cup!
    Last edited by Grizzly; 10-12-2017 at 12:26 AM.
    Despite the High Cost of Living it still remains Popular!

  5. #5
    Join Date
    Dec 2007
    Location
    australia
    Posts
    2,475
    Rep Power
    27

    Re: Bad Day - Good day.

    Quote Originally Posted by Grizzly View Post
    Ranger.
    Thank you for the complement my friend.
    I just thought it was an amusing story and one which some will remember for future reference.

    We all learn from those we work with and I count myself lucky to work with some of the guys I do!
    (Young and Old)
    I know from talking to you, that you are lucky to be able to occasionally impart your vast knowledge to younger colleagues.

    Sadly the days of there being two of you on a job are pretty rare over here Nowadays.
    Certain ammonia Jobs still necessitate 2 but even they are infrequent.

    But We Do have the Forum for those little Gems!


    Do you remember my story about the Vending Machine plastic cup!
    Could you remind us thanks Ranger

  6. #6
    Join Date
    Sep 2007
    Location
    Somerset
    Age
    63
    Posts
    4,518
    Rep Power
    38

    Re: Bad Day - Good day.

    It must of been a long time ago, because I have just trawled my last 500 posts and cannot find it!

    OK.
    So several of us were looking after some rooftop Chillers which would randomly lock out on "No Run Permit".

    Effectively meaning BMS turned the pumps off or the flow switch in the chilled water circuit failed!


    This had gone on for 2 or 3 yrs without resolution.

    When one day my old Friend and now retired Colleague Paul.
    Lifted the lid of the Header Tank to see a semi submerged Plastic vending machine coffee cup!
    It transpired that the site maintenance engineer responsible for Daily / weekly checking of the chilled water condition.
    When challenged admitted that.
    He had a cup on a stick which he would dip into the water tank to take a sample.
    However one day the cup fell off the stick, He replaced it with a new cup.
    And thought no more of it!
    The old cup would circulate at various depths around the tank.
    If the Pumps started with the cup in the wrong place at the wrong time in would be drawn into the pipe supplying the Pumps.

    Creating a perfect Plug and stall the Chillers.
    When the pump/s stopped the backwash would blow the plastic (Non return valve!!) cup back out of the pipe and normal service would resume.
    Pure Luck and a inquisitive Engineer resolved that one.

    The problem we all face nowadays is as the more complex the electronic controls become on the plant.
    The harder it is to diagnose even basic faults.


    Cheers Guys!
    Grizzly
    Last edited by Grizzly; 10-12-2017 at 02:18 PM.
    Despite the High Cost of Living it still remains Popular!

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