Results 1 to 3 of 3

Thread: Free Cooling

Hybrid View

  1. #1

    Free Cooling

    When designing a building with free cooling features using air-side economizer, what range of the RH and temperature sensors should be set to avoid excessive turning on/off of the compressor?

  2. #2
    Join Date
    Nov 2003
    Location
    Rochester, New York
    Posts
    392
    Base it on OA wet bulb. Mine is set to run free cooling if the WB is below 41* with process. 48* without process. This is a plate and frame HX around 950 tons.

  3. #3
    Join Date
    Feb 2006
    Location
    SouthEastern Virginia
    Posts
    1,077
    This is fairly simple if the equipment is designed correctly. First of all comparative enthalpy is the best method of economizer control. If the return enthalpy is lower than the outdoor enthalpy, then the outdoor damper goes to minimum position. If the outdoor enthalpy is lower than the return enthalpy, the outdoor damper is opened. If the RTU must stage mechanical cooling along with the outside air then short cycling can be an issue. I would set the enthalpy control to the lowest setting if you live in a high humidity area and make sure you have a low ambient kit to maintain a stable head pressure during cooler weather. What model equipment are you talking about?
    It might get loud!

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event