Results 1 to 1 of 1
  1. #1
    Join Date
    Sep 2019
    Location
    Northern Ontario
    Posts
    38
    Post Likes

    Return fan needed on meeting room AHU?

    Existing rooms were converted to our main meeting room in the 1980's. Approx 30' x 40' seats 180 people. It is an indoor ahu (Sheldons 4LP-2000) that consists of a supply fan and a heating coil and a cooling coil. Looks to be around 4000 cfm. There are 3 sets of dampers. Outdoor air inlet, mixed air and return air exhaust to outside. Original plans don't show a return fan.

    Fast forward to today. There is a return fan in place now, installed in 80's or 90's. The ducting at this return fan, seemingly do to limited space issues, is way undersized. 3 x 10" round flex ducts for that 4000 cfm. This is causing lots of noise and slow temperature response.

    Generally speaking, when would you install one or not? I ask because it was not originally spec'd and our cafeteria has almost the same system but no return fan.

    Thank you for any responses,

    Currently looks like this setup
    Name:  AirHandlingUnit_FreeCooling-700x650.png
Views: 116
Size:  294.0 KB
    Last edited by Gdh33; 09-20-2019 at 08:02 PM. Reason: Added photo

Posting Permissions

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