Results 1 to 3 of 3
  1. #1
    Join Date
    Aug 2011
    Post Likes


    I would just like to know why my Discharge Air humidity drops when heating is enabled i.e when i open my heating valve my DA-H starts dropping.

  2. #2
    Join Date
    Aug 2003
    Post Likes
    Warm air can carry more water. For the same weight of water, the % capacity used decreases when you heat the air.
    -If you won't turn it on then nothing else matters.

  3. #3
    Join Date
    Mar 2001
    Washington DC
    Post Likes
    Pmeunier has it right. Humidity can be evaluated as either absolute or relative, most of the time when we measure it we're measuring it as relative. Since warm air can carry more moisture than cold air, a given amount of water in cold air is larger _relative_ to it's capacity to hold water compared to warm air. So air that has been simply warmed up (and therefor has the same water content as before heating) has lower relative humidity than it did before heating.

Tags for this Thread

Posting Permissions

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

Related Forums

Plumbing Talks | Contractor MagazineThe place where Electrical professionals meet.