Page 1 of 2 12 LastLast
Results 1 to 13 of 15
  1. #1
    Join Date
    Jul 2011
    Location
    Tucson, AZ
    Posts
    106

    Heat Pump Metering Device (indoor unit)

    Is this an orifice or capillary tube metering device and why is there no check valve?
    Attached Images Attached Images  

  2. #2
    Join Date
    Jan 2008
    Location
    In the work truck
    Posts
    2,990
    Quote Originally Posted by greenhorn520 View Post
    Is this an orifice or capillary tube metering device and why is there no check valve?
    Are you in the Trade? We can't give much technical advice to homeowners..
    Gotta have the right tool for the job!

    Where is all the stuff MADE IN THE USA?

    "Thats what we do Troy. Incredible, Invisible, Imbelivable things. We are an Unseen, Unknown, Unvincible fraternity of craftsman.."

  3. #3
    Join Date
    Jul 2011
    Location
    Tucson, AZ
    Posts
    106
    I am a student trying to learn. I may be entering the trade very soon. I just read about heat pump metering devices and it sounds like most of them use a check valve, although it did say refrigerant can flow either way through a capillary tube. This is the unit in the place I live.

  4. #4
    Join Date
    Mar 2004
    Location
    Grottoes VA
    Posts
    5,856
    What you have is a piston coil. A check valve would be on a system with a TXV, not all TXV systems have check valves.
    Karst means cave. So, I search for caves.

  5. #5
    Join Date
    Jan 2008
    Location
    In the work truck
    Posts
    2,990
    Quote Originally Posted by greenhorn520 View Post
    I am a student trying to learn. I may be entering the trade very soon. I just read about heat pump metering devices and it sounds like most of them use a check valve, although it did say refrigerant can flow either way through a capillary tube. This is the unit in the place I live.
    Where were you reading this at? A lot of the textbooks show piping schematics.
    If there was a check valve you would see a bypass line around the MD.
    The Flowrater is not restricting flow in the other direction. Again not going into much detail.

    Its a good trade. Very rewarding if you ask me!
    Gotta have the right tool for the job!

    Where is all the stuff MADE IN THE USA?

    "Thats what we do Troy. Incredible, Invisible, Imbelivable things. We are an Unseen, Unknown, Unvincible fraternity of craftsman.."

  6. #6
    Join Date
    Jul 2011
    Location
    Tucson, AZ
    Posts
    106
    I'm reading this in my 1200 page text book, it's hard to interpret every detail I read, some times things need to be explained in more than one way. And yes I realize there would be a bypass line for the check valve. BTW, the book also shows check valves with the the capillary tube set-up, not just with the TXV. It does show the piston coil/flowrater not with check valve, but I don't remember it referring to that device by those names.

  7. #7
    Join Date
    Jun 2008
    Location
    phoenix az
    Posts
    24

    Piston flow rater

    Its metering only in one direction, it bypasses around piston in the holder during heating

  8. #8
    Join Date
    Jul 2011
    Location
    Tucson, AZ
    Posts
    106
    I've rented two places with heat pumps, one was a package unit (not very old), and the other an old split system. They seem to be pieces of crap. The package unit would go into defrost mode too often and for too long. The one I have now has an intermittent problem where the compressor doesn't run, it just circulates what ever air is in the house(heating and cooling mode). In both experiences techs looked at them many times and never fixed them right. I don't think I like heat pumps.

  9. #9
    Join Date
    Jun 2008
    Location
    phoenix az
    Posts
    24
    Quote Originally Posted by greenhorn520 View Post
    I've rented two places with heat pumps, one was a package unit (not very old), and the other an old split system. They seem to be pieces of crap. The package unit would go into defrost mode too often and for too long. The one I have now has an intermittent problem where the compressor doesn't run, it just circulates what ever air is in the house(heating and cooling mode). In both experiences techs looked at them many times and never fixed them right. I don't think I like heat pumps.
    Sounds like to me you just live somewhere where it gets real cold and techs there dont work on heat pumps very often. Here in phoenix az, heat pumps are king, and they work great. You just need to find a tech that know his way around one.

  10. #10
    Join Date
    Jul 2011
    Location
    Tucson, AZ
    Posts
    106
    I live in Tucson actually.

  11. #11
    Join Date
    Jun 2008
    Location
    phoenix az
    Posts
    24
    Quote Originally Posted by greenhorn520 View Post
    I live in Tucson actually.
    In that case, you should find someone who can easily fix the problem

  12. #12
    Join Date
    Jul 2011
    Location
    Tucson, AZ
    Posts
    106
    That's what I thought, but apparently it's not that easy because my previous and current landlords have not been able to accomplish that.

  13. #13
    Join Date
    Jul 2002
    Location
    Yuma, AZ
    Posts
    2,361
    Quote Originally Posted by hvacguru69 View Post
    Its metering only in one direction, it bypasses around piston in the holder during heating
    Exactly right.
    "I have never let my schooling interfere with my education."
    Mark Twain
    More at: http://www.quotationspage.com/subjects/education/

Page 1 of 2 12 LastLast

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