Results 1 to 6 of 6
  1. #1
    Join Date
    Jul 2011
    Location
    Ireland
    Age
    36
    Posts
    18
    Rep Power
    0

    Humidity Control in a Comms Room



    Hi

    I am working on a site. it is a brand new built building. The building is now coming near the end of its complateion and will soon be handed over to the customer. i am commissioning a close control AC unit within the comms room in the basement of this building. I have set my humidity setpoint to 45%, my low alarm sepoint is 30% and my high is 70%. the humidity in this room seems to fluctuate alot and doesnt remain consistent at its setpoint. The comms room isnt live yet so there isnt much of a load in the room.

    The supplier of the unit has told me that due to it being a newly built building and te fact that there is no real load in the room, the unit will not be able to maintain consistent humidity levels at 45% and that the RH reading will fluctuate.

    My question is if anyone would know, why would this be the case? how could the fact it is a newly built building affect my RH reading? and how could no load in the room affect my rh reading?



  2. #2
    Join Date
    Mar 2009
    Location
    Uk
    Age
    41
    Posts
    121
    Rep Power
    17

    Re: Humidity Control in a Comms Room

    What's the diff for the set point? How much fluaction are you getting? Have you seen the humidifier bottle working? Is the room a sealed room?

  3. #3
    Brian_UK's Avatar
    Brian_UK is offline Moderator I am starting to push the Mods: of RE Site Moderator : and general nice guy
    Join Date
    Mar 2001
    Location
    Dorset
    Age
    76
    Posts
    11,192
    Rep Power
    60

    Re: Humidity Control in a Comms Room

    You haven't stated your operating temperature.

    How stable is the room temperature in the empty state?

    %RH follows the temperature so compare your readings with a psychrometric chart to see if you are getting any unstable conditions.

    Had a situation many years ago where the humidity rose suddenly in a room being dried out around the same every day. Found a cleaner came to sweep up the dust. How did he control the excess dust? Simple, he threw a bucket of water over the floor before he swept it up.

    You never can tell.
    Brian - Newton Abbot, Devon, UK
    Retired March 2015

  4. #4
    Join Date
    Oct 2001
    Location
    Nottingham UK
    Posts
    5,733
    Rep Power
    51

    Re: Humidity Control in a Comms Room

    Without a heat load, the cooling isn't doing any real work, so the latent heat removal is minimal. This means that your design levels are not being reached.

    At this point, your installed equipment is oversized, therefore, cooling and humidity control will be difficult due to on/off times of your kit.

    It's like trying to set superheat on a freezer room when you have just had an ambient delivery.

  5. #5
    Join Date
    Apr 2016
    Location
    New York
    Posts
    2
    Rep Power
    0

    Re: Humidity Control in a Comms Room

    A common mistake generally done is to only depend upon the monitoring the conditions at room level and not at rack level. ASHRAE recommends 9 temperature sensors per rack
    Last edited by frank; 10-04-2016 at 06:56 AM.

  6. #6
    Join Date
    Jul 2010
    Location
    NTH.QLD Australia
    Age
    62
    Posts
    1,762
    Rep Power
    32

    Re: Humidity Control in a Comms Room

    Without something to chew on, your A/C is going to power down and have bugger-all influence on Humidity.
    To the optimist, the glass is half full. To the pessimist, the glass is half empty.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •