Page 2 of 2 FirstFirst 12
Results 14 to 19 of 19
  1. #14
    Join Date
    Jan 2004
    Location
    Lancaster PA
    Posts
    67,875
    Quote Originally Posted by stemps22 View Post
    yeah i thought about the unmatched possibility ill get the m/s numbers but no i got the trurn air with a ductulator duct is sealed and not kinked so i figured it was pretty close thanks for the tip about superheat though. makes sense.
    You figured out return air flow with a duculator?
    Contractor locator map

    How-to-apply-for-Professional

    How many times must one fix something before it is fixed?

  2. #15
    Join Date
    Oct 2012
    Location
    Sacramento,ca
    Posts
    196
    [QUOTE=gravity;15287331]Sounds to be over charged in heating.

    You need 450cfm/ton for heating mode.

    Where do you get this number? I do heatpumps all the time and have never got them to pull 450cfm/ton and they work great. All specs i have ever seen say 375 -400 a ton is fine. Or am i wrong?

  3. #16
    Join Date
    Jul 2009
    Location
    South Carolina
    Posts
    3,176
    The SST is warmer than the outdoor air.
    The possible causes I can think of are overcharge, metering device over feeding & low indoor airflow.
    We can eliminate the outdoor TXV over feeding so there's not much left. I wouldn't be surprised if it had both low airflow & was over charged.
    Gary
    -----------
    http://www.oceanhvac.com
    An engineer designs what he would never work on.
    A technician works on what he would never design.

  4. #17
    Join Date
    Feb 2013
    Location
    Florida
    Posts
    69
    [QUOTE=Barrettservices;15296451]
    Quote Originally Posted by gravity View Post
    Sounds to be over charged in heating.

    You need 450cfm/ton for heating mode.

    Where do you get this number? I do heatpumps all the time and have never got them to pull 450cfm/ton and they work great. All specs i have ever seen say 375 -400 a ton is fine. Or am i wrong?
    Heat mode calls for the same airflow as cooling. 400 +/- 50 a ton

  5. #18
    Join Date
    Jul 2009
    Location
    Columbia, MD
    Posts
    3,834
    heating needs more airflow because the coil is smaller. look it up

  6. #19
    Join Date
    Oct 2012
    Location
    Sacramento,ca
    Posts
    196
    Quote Originally Posted by gravity View Post
    heating needs more airflow because the coil is smaller. look it up
    I did and in every rheem air handler manual i looked into they show the same cfm for heat or cool mode with a chart that shows cfm compared to static pressure and not one is over 400 cfm/ton and they will even accept as low as 350cfm/ton. Also we are regulated in california by calcerts and they never test for anything over 350cfm/ton period.

    Where are you seeing this?

Page 2 of 2 FirstFirst 12

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