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  1. #27
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    Quote Originally Posted by Boiler Guy View Post
    Vacuum pumps. I was surprised when the instructor for the Daikin centrifugal class suggested using only a 5-10cfm pump for evacuation. What kind of vacuum pumps are typically used? Im sure the bigger the get the bigger the vacuum pumps get.
    Every tried carrying a 300lb 30cfm Welch vacuum pump up two flights of stairs on your own ?
    Two 8cfm yellow jackets will do the job and easier on the body .
    The toy chest is officially full ... I got a new toy..... 2007 Aston Martin V8 Vantage and yes it still gives me goosebumps
    You bend em" I"ll mend em" !!!!!!!
    I"m not a service tech.. I"m a thermodynamic transfer analyst & strategic system sustainability specialist
    In the new big shop , greasin', oilin' . tweakin' n shinin' !!

  2. Likes CHILLERSVCMAN liked this post
  3. #28
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    Mar 2015
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    Please explain the surge caused by low condenser water temp? Unless you are referring to a low load stall due to insufficent gas velocity.

    Sent from my SM-P550 using Tapatalk

  4. #29
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    Thread Starter
    What size vacuum pump do you guys use on chillers? Does it change depending on the chiller?

  5. #30
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    Aug 2006
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    Quote Originally Posted by Boiler Guy View Post
    What size vacuum pump do you guys use on chillers? Does it change depending on the chiller?
    The general rule of thumb is 10’tons per cfm or vacuum pump. Example: 7 cfm pump is good for a 70 ton unit or smaller. I have a 6 and an 8 cfm pump. I use them on chillers as high as 3000 tons. If I had a few more pumps, I would add them. So, in the end, more pumps are better than big pumps. Big hoses are better then small hoses and watch your oil levels while evacuating.
    Don't step on my favorite part of the Constitution just to point out your favorite part.

    Political Correctness is forced on you because you have forgotten decency.

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  7. #31
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    Jan 2010
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    Also a 72 pack of Duracells is better then 2 crappy Chinese batteries.......

    Sent from my SM-N910W8 using Tapatalk

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  9. #32
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    Thread Starter
    Quote Originally Posted by jayguy View Post
    The general rule of thumb is 10’tons per cfm or vacuum pump. Example: 7 cfm pump is good for a 70 ton unit or smaller. I have a 6 and an 8 cfm pump. I use them on chillers as high as 3000 tons. If I had a few more pumps, I would add them. So, in the end, more pumps are better than big pumps. Big hoses are better then small hoses and watch your oil levels while evacuating.
    So you can use multiple different vacuum pumps at the same time? Do you attach them to a common manifold or different parts of the chiller?

    What are good sealants to use on gasket surfaces?

  10. #33
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    Quote Originally Posted by Boiler Guy View Post
    So you can use multiple different vacuum pumps at the same time? Do you attach them to a common manifold or different parts of the chiller?

    What are good sealants to use on gasket surfaces?
    Multiple points, not manifolded. What gasket surfaces are you talking about?
    Don't step on my favorite part of the Constitution just to point out your favorite part.

    Political Correctness is forced on you because you have forgotten decency.

  11. #34
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    Thread Starter
    Quote Originally Posted by jayguy View Post
    Multiple points, not manifolded. What gasket surfaces are you talking about?
    For example, flange gaskets on the WMC refrigerant lines.

  12. #35
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    Quote Originally Posted by Boiler Guy View Post
    For example, flange gaskets on the WMC refrigerant lines.
    i don't know. i am not a McQuay rep. we typically use grape jelly or Parker Oring+ sealant if we use anything.
    Don't step on my favorite part of the Constitution just to point out your favorite part.

    Political Correctness is forced on you because you have forgotten decency.

  13. #36
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    GRAPE JELLY GOOD ! ! ! AKA Loctiite 515 . Have seen where it was used in excess --- BAD ! Vanes were locked-up . Good for me OT 4th July in DC .

  14. #37
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    Mar 2017
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    Orange County, CA
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    Dow Corning molykote 111 is what I use on a lot of gaskets or O-rings. They sell it at trane here in California.


    Sent from my iPhone using Tapatalk

  15. #38
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    Jun 2018
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    Hi Guys

    I have installed a 3.3kkV Vacuum Contactor for Centrifugal Carrier Chiller. During the Start Up when the ISM gives signal to Vacuum Contactor the MPR activates immediately . When checked it shows Thermal Overload Trip. very fast trip. Can anyone advise what would be the possible reason?

    The Current drawn in Yellow Phase is higher that 2 other Phases

    if have any advise kindly email to shelorveengineering@gmail.com

  16. #39
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    Quote Originally Posted by navenia View Post
    Hi Guys

    I have installed a 3.3kkV Vacuum Contactor for Centrifugal Carrier Chiller. During the Start Up when the ISM gives signal to Vacuum Contactor the MPR activates immediately . When checked it shows Thermal Overload Trip. very fast trip. Can anyone advise what would be the possible reason?

    The Current drawn in Yellow Phase is higher that 2 other Phases

    if have any advise kindly email to shelorveengineering@gmail.com
    Please start a new thread when discussing something completely different. Also, don’t put your email address in the posts.
    Don't step on my favorite part of the Constitution just to point out your favorite part.

    Political Correctness is forced on you because you have forgotten decency.

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