Page 2 of 3 FirstFirst 123 LastLast
Results 14 to 26 of 30
  1. #14
    Join Date
    Apr 2003
    Location
    California
    Posts
    634
    as an HVAC/R tech the only thing you should be soldering is a condensate drain line, you should always braze refrigerant lines..

  2. #15
    Join Date
    Dec 2003
    Location
    Nevada
    Posts
    1,815
    If you heat the fitting the solder is drawn in by capillary action. That is why we were taught to solder until a fillet appears around the joint. After the fillet has appeared if solder is added it just flows into the inside of the joint (try it). Another important thing is to always use a nitrogen purge when soldering.

    Are you mil or civ at Eglin?
    Quote
    “Engineers like to solve problems. If there are no problems handily available, they will create their own." Scott Adams

    "We can't solve problems by using the same kind of thinking we used when we created them."
    Albert Einstein

  3. #16
    Join Date
    Aug 2002
    Location
    manitowoc wisconsin
    Posts
    4,943
    preheat the male pipe at a 20 deg.angle toward the female & then go to the bottom of the female fitting drawing the filler throughout the entire fitting.Your instructor should not be teaching how to braze IMO..........Take a saw & cut one of those "face soldered" joints through the middle on a diagonal.You will see & have proof what a crappy job he taught you to do!
    Take your time & do it right!

  4. #17
    Originally posted by hvacbear
    Another important thing is to always use a nitrogen purge when soldering.
    Why do you feel its necessary to purge while soldering?

  5. #18
    Originally posted by bittan
    Where did you read that Carrier requires lineset and filter drier brazing for their 410 systems. Would like the reference.
    Technical Bulletin # TB98-04B, dated 11/12/98


    [Edited by jultzya on 08-26-2005 at 01:59 AM]

  6. #19
    thanks to everyone for the inputs....Consensus is to the draw the solder in.....P.S. I always braze with 15% sil fos.... been doing it for 9 years in the field...never sucked it in and never had a leak.. always built the bell/shoulder up so no ridge was visible...less chance of contaninants getting into the pipe....


  7. #20
    books say to have a slight amount of nitrogen going through the lines being soldered to prevent the black flaking inside the line set, which could break free and block your metering device or cause other problems/restrictions....Not sure exactly how it prevents the flaking problem

  8. #21
    Yes (for brazing), not for soldering.

    BTW, it prevents oxidation by displacing the oxygen with nitrogen (oxygen is required to have oxidation).

  9. #22
    Join Date
    Dec 2003
    Location
    Nevada
    Posts
    1,815
    Originally posted by jultzya
    Yes (for brazing), not for soldering.

    BTW, it prevents oxidation by displacing the oxygen with nitrogen (oxygen is required to have oxidation).

    Exactly! (We were using brazing and soldering interchangeably).
    When I require a nitrogen purge I have had many people say that is what the filter-drier is for. Well that is the same as piping in a pump and getting dirt in the piping and saying that is what the strainer is for. The only problem is strainers and filter-driers clog up creating an unnecessary restriction in the system. Do a test on a joint with and without nitrogen you can see a difference.
    Quote
    “Engineers like to solve problems. If there are no problems handily available, they will create their own." Scott Adams

    "We can't solve problems by using the same kind of thinking we used when we created them."
    Albert Einstein

  10. #23
    Join Date
    Dec 2003
    Location
    Nevada
    Posts
    1,815
    trapper101,

    Are you military or civilian at Eglin?
    I am military at Davis-Monthan AFB,AZ.
    Quote
    “Engineers like to solve problems. If there are no problems handily available, they will create their own." Scott Adams

    "We can't solve problems by using the same kind of thinking we used when we created them."
    Albert Einstein

  11. #24
    hvacbear

    Retired military... Currently working A/C field at CE HVAC shop

  12. #25
    Join Date
    Jun 2001
    Location
    Louisville, KY
    Posts
    12,189
    Originally posted by jultzya
    Originally posted by bittan
    Where did you read that Carrier requires lineset and filter drier brazing for their 410 systems. Would like the reference.
    Technical Bulletin # TB98-04B, dated 11/12/98


    [Edited by jultzya on 08-26-2005 at 01:59 AM]
    and here: http://www.xpedio.carrier.com/idc/gr...it/38-11sm.pdf. Page 22.

  13. #26

    Capillary Attraction

    This technique is referred to as capillary attraction. Research this subject and the answers and scientific explanation on what actually happens to the metals is found here.

Page 2 of 3 FirstFirst 123 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