Results 1 to 6 of 6
  1. #1
    Join Date
    Jun 2005
    Location
    Ohio
    Posts
    1,716
    We're installing a Carrier chiller with an air-cooled condenser. The Carrier rep said we needed a double riser on the discharge line due to unloading and the condenser being 10+ feet above the chiller. System is 134a. I do not have the models, just heard about it at our shop.
    Anyone heard of this?
    jogas

  2. #2
    Join Date
    Jul 2005
    Location
    Orange County, NY
    Posts
    936
    Years back I piped a McQuay chiller the same way. Four compressors and the discharge manifold teed off to two lines.

    The evap. cooler was about 10 feet above the compressors. The only mistake we made was not putting isolation valves in, recovering all 600 lb’s was a nightmare when you had a small leak to fix.


    Core

  3. #3
    Join Date
    Jan 2005
    Location
    steeler nation
    Posts
    2,025
    for oil return at reduced load.

  4. #4
    Join Date
    Jan 2004
    Posts
    300
    Do yourself a favor and purchase a good refrigerant piping guideline. Trane makes a very good one. I can't tell you how many calls I've been on where the new/old equipment wasn't piped correctly and it was a nightmare for the contractor to straiten out.

    For the situation you describe, and double riser is recommended.

  5. #5
    Join Date
    Jun 2005
    Location
    Ohio
    Posts
    1,716
    I am well aware of double risers as used for capacity controlled systems to provide a hi and low capacity line riser. I just don't ever remember seeing a double riser discharge line. I usually expect to see a p-trap at the bottom and an inverted p trap at the top. I remember a hi-rise building with a Carrier chiller that ran 5 stories up and no double riser (R-22). Just p-traps.
    I really thought this double suction discharge was for 134A only.
    jogas

  6. #6
    Join Date
    Apr 2005
    Location
    where the beer flows like wine
    Posts
    2,871
    the single riser wont allow for the +/- 1000fpm velocity at minimum load,you could use an oil separator instead of the double riser set-up.

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