Results 1 to 5 of 5
  1. #1
    Join Date
    Dec 2011
    Location
    Hiram, Ohio
    Posts
    214

    Been reading the manual again..

    Goodman 16 seer 2 stage HP coupled with a modulating furnace and top of the line stat... Goodman wants the charge checked (superheat and supercool) on LOW stage AC.. Manual says nothing about checking charge in heat mode, which from what I understand by lurking and reading on this sight is much more finicky. And why on LOW stage AC and not HIGH stage? Thanks, Mike.

  2. #2
    Join Date
    Dec 2011
    Location
    Hiram, Ohio
    Posts
    214
    Hello, anyone have thoughts on this? It just seems funny to me to not check charge when running full throttle! Just does not seem logical.

  3. #3
    Join Date
    Oct 2010
    Location
    Anderson, South Carolina, United States
    Posts
    6,720
    I don't know they would want to check it on low, other than to make sure that the 2 stage compressor is operating within parameters on low speed. The only correct way to charge is in air conditioning mode on high speed by superheat(fixed orifice metering device) or subcool(TXV). or weigh in the complete charge.
    Heating/Cooling Services Inc.
    www.andersonhvacservice.com

  4. #4
    Join Date
    Jan 2004
    Location
    Lancaster PA
    Posts
    67,875
    Quote Originally Posted by troyport View Post
    Hello, anyone have thoughts on this? It just seems funny to me to not check charge when running full throttle! Just does not seem logical.
    Its the way they want, and have apparently proved works best on their units.
    Contractor locator map

    How-to-apply-for-Professional

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

  5. #5
    Join Date
    Aug 2004
    Location
    North Richland Hills, Texas
    Posts
    14,914
    The first time we put in a Goodmana 2 stage system, I thought the instructions to do the TXV setup, and refrigerant charging, in low speed was a bit odd.
    It makes sense though, the majority of the systems operation should be in 1st stage, so why not optimize it for that?
    Goodmana is one of the only manufacturers that supplies adjustable TXVs with their equipment.

    The only issue I have with it is that, like Lennox, they call for fairly low subcooling values.
    Most of our applications have longish refrigerant line sets, and/or >20' of lift, so I have to charge to significantly higher subcooling to avoid capacity loss due to flash gas in the cooling mode.
    It isn't an issue most of the time, but they do have some ARI rated indoor coil + heat pump combinations that can't handle the extra refrigerant in the heat mode.
    If more government is the answer, then it's a really stupid question.

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