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Flaring line sets for mini splits.

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Comments

  • SWEI
    SWEI Member Posts: 7,356
    edited December 2014
    Anyone tried Reflok? I've seen a couple of large jobs here done with it and was quite impressed http://reflok.com/
  • Techman
    Techman Member Posts: 2,144
    edited December 2014
    SWEI, darn you, now I have to read also?!? This reflok is new to me, Thanks. What size are the jobs that you are talking about?
  • SWEI
    SWEI Member Posts: 7,356
    Multi-story commercial Daikin VRV systems, 100 tons give or take. Before I looked at the site this morning, I had assumed they were only for larger sizes -- now I see they go all the way down to 1/4" lines and there's a new handheld electric tool coming. Could get interesting.

    The technology comes from aircraft hydraulics, a rather demanding application.
  • Jack
    Jack Member Posts: 1,046
    Guys, I'm on thin ice here so I'll go lightly, but specifically, what tools do you use, brand and model for these connections. Personally, I use the Yellow Jacket flaring tool. The first flare I did with that led me to take my old plumbing flaring tool and throw it in the trash.
  • Techman
    Techman Member Posts: 2,144
    We consider the vac pump as just a regular ole' vac pump. There are some slight variations, like 1stage/2stage and the CFM's vary, the cost is $300-400-500 $600. The auto vac pump is the same so the micron level is also the same. Some auto guys are just like some ACR guys, they don't really care. I happen to have 8 vac pumps, 3 of them are BIG ($1200.00 or so 30 years ago)and belt driven,these are for 20-30T refrig (or AC)systems with 1 1/8 liquid lines and 2 1/8 suction lines with 100' of line sets. I hooked up two of the BIG vac pumps on one system and pulled a good vac in 10-12hrs. Then on the other hand I had all 3 BIG vac's and 1 smaller vac on one "blast freezer"( for Long Island Ducks) that took 4days and GALLONS of Vac Pump Oil to pull " just a decent" vac. I was on site for the entire repair, 30-40 people were out of work for awhile. Cases(12) of filter driers were changed.
  • Harvey Ramer
    Harvey Ramer Member Posts: 2,221
    On a new residential AC, I can pull under 500 microns in less than a minute. That's with a 2stage 8 cfm vacuum pump and the proper equipment. I leave it under a vacuum until the moisture is boiled off, as indicated by the "leak rate indicator" on the micron gauge. Whether I double vac or triple vac depends largely on the system condition and ambient temperature.

    I can hold a stable vacuum under 300 microns.

    Now pulling down the condensor unit takes longer. You have to pull out all the refrigerant from the oil slump in the compressor. That can take a while, especially in cold weather. It helps to take a heat gun and warm up the compressor body.

    All you need is the right equipment, good hoses and a perspective of what's happening inside the pipes.
  • Techman
    Techman Member Posts: 2,144
    Not at all, on the time. Using dry nitro will absorb some moisture, purging w/ nitro gets rid of most of the "non-condensibles", getting rid of the non-condensibles allows the vac pump to attack the lower 10,000 microns in a hurry,not even an hour in some cases. The micron gauge will tell you when the vac is over and done with.On board the truck I carry a smallish 8cfm vac pump for "every day" work.
  • Larry_52
    Larry_52 Member Posts: 181


    The service valves connect the line sets with flares on a mini split. Are you suggesting the charge should be removed from the unit, the service valves be removed or changed and new sweat ones be installed just to avoid some flare connections?

    You need to give the engineers that design these units some credit for knowing what works. They have the field data of failure rates and they know that a PROPERLY done flare is preferred over the possibility of incompetent installers brazing without N2 or attempting to soft solder the lines.

    FYI, I use a double flare tool on every flare on any type of flared line and I have NEVER had a leak in 15 years with this method.

    Putting LeakLoc on the flare surface is a very poor recommendation since some is very likely to get into the refrigerant circuit and cause a restriction in a capillary somewhere - the very reason that the flare was chosen over brazing.

    Get a good double flare tool and a flare torque wrench and learn to use them correctly. And leave the LeakLoc on the shelf when doing mini splits.

    Love when people get excited on a message board. Where did I recommend evacuating an entire system then removing the valves and brazing in a new one? Yes, yes flares work but it is a simple issue: a brazed joint is just one joint; one flared joint is two. One place to leak versus two, simple. I have performed both when the situations context benfits using one over the other. If I had to chose my opinion is a proper brazed joint is just better. The flared end of the line set to the condenser valves is easily accessed, the connection (better brazed) to the evap is typically buried and difficult to get to in relation. That is what I meant and I am sure you understood.

    There is a simple reason brake lines are double flared, pressure and cost. One weak point of a flare is its ability to pull out, based on the bearing surface clamp force. This is why brake lines use double flares and a specific double flare nut. The next weakness is they can vibrate and snap, which is why brake lines are steel. When using 410A it requires a specific long nut to maintain proper clamp (for rated 410A pressure) of the copper flared end. Leak loc or oil on the flare is for the backside bearing surface of the flared joint to lubricate it when you tighten the nut and do not twist the copper as you seat it.

    If you want to sound smart try saying I only use 37deg JIC or AN flares with sleeves, then I would have crawled away and said man this guy has got his [email protected]% together.

    Mini splits do not have capillary tubes. Leak Lock is a good way to lubricate the bearing surface of a flared joint as it will not contaminate the refrigerant. We are not talking about buttering it like your toast.

    All these recommendations of using double flares for a standard or long SAE flare nut is not correct. First off copper is only for single flares as it cannot handle the fold over and will just crack on the larger OD lines, second the double flare nut is an inverted nut meaning it has the male threads and the recieving end has the female. Each flare requires specific contact area and bearing surface area. Each flare has its specific nut to accomplish this and can be specific to the material being flared.

    And 500 microns is not even that anal, Mitshubishi recommends 200 microns for one hour for their units. I too remember when 28"Hg was good to go, many people have not been educated in the new refrigerant requirements. R134A is NOT as "touchy" as R410A and does not require the same surgical precision of evacuation.


  • Techman
    Techman Member Posts: 2,144
    I'm for another beer. When a said flare connection is "not good" as stated I KindaSorta took that to mean that "flare "connections "would/will" leak and get rid of them in preference of solder/swag connections which are "better".
    I do happen to get very excited about this ACR stuff and I do like to better at 0900 as compared to 0800 hrs ,every day!
    Now I do happen to take issue with "not being able to make a proper flare connection" .Yea the "odds" are better with 50 swag fitting as compared to 100 "other"(flare) fittings but, again "damn dude", I can't make 10,000 flare fitting properly and another 10,000 after that ,and after that, and after that!?!? I am a professional, at least I believe I am.
    I was not/ am not aware that r410a uses a "special" "long neck/not long neck" SAE 45* flare nut. I thought the "long neck"SAE nuts were for AC only as compared to "R" (short neck) where the frost/freezing would "build up"in the long neck and cause problems.
    I think that "200"( more anal vs. a 500 not as much anal) microns is much harder to obtain than "500" microns.And I do not remember when 28"hg( about 600,000 removed microns WAS acceptciable as compared to a proper( and deeper/lower/longer to get to) 749,500 removed microns.
    Now ,ANY/ALL thread sealant's are for the "space/air gap/moisture containing space" between the THREADS ONLY. Beginning/middle/end, perioid!!!!. REGARDLESS of the "freon" used a "normal/proper" vac is required, ACROSS THE BOARD, R22-R502-R410a-R404 -R134a and on and on.

    BEERTENDER , ANOTHER BAR PLEASE!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
  • Ironman
    Ironman Member Posts: 6,900
    Larry said:



    The service valves connect the line sets with flares on a mini split. Are you suggesting the charge should be removed from the unit, the service valves be removed or changed and new sweat ones be installed just to avoid some flare connections?

    You need to give the engineers that design these units some credit for knowing what works. They have the field data of failure rates and they know that a PROPERLY done flare is preferred over the possibility of incompetent installers brazing without N2 or attempting to soft solder the lines.

    FYI, I use a double flare tool on every flare on any type of flared line and I have NEVER had a leak in 15 years with this method.

    Putting LeakLoc on the flare surface is a very poor recommendation since some is very likely to get into the refrigerant circuit and cause a restriction in a capillary somewhere - the very reason that the flare was chosen over brazing.

    Get a good double flare tool and a flare torque wrench and learn to use them correctly. And leave the LeakLoc on the shelf when doing mini splits.

    Love when people get excited on a message board. Where did I recommend evacuating an entire system then removing the valves and brazing in a new one? Yes, yes flares work but it is a simple issue: a brazed joint is just one joint; one flared joint is two. One place to leak versus two, simple. I have performed both when the situations context benfits using one over the other. If I had to chose my opinion is a proper brazed joint is just better. The flared end of the line set to the condenser valves is easily accessed, the connection (better brazed) to the evap is typically buried and difficult to get to in relation. That is what I meant and I am sure you understood.

    There is a simple reason brake lines are double flared, pressure and cost. One weak point of a flare is its ability to pull out, based on the bearing surface clamp force. This is why brake lines use double flares and a specific double flare nut. The next weakness is they can vibrate and snap, which is why brake lines are steel. When using 410A it requires a specific long nut to maintain proper clamp (for rated 410A pressure) of the copper flared end. Leak loc or oil on the flare is for the backside bearing surface of the flared joint to lubricate it when you tighten the nut and do not twist the copper as you seat it.

    If you want to sound smart try saying I only use 37deg JIC or AN flares with sleeves, then I would have crawled away and said man this guy has got his [email protected]% together.

    Mini splits do not have capillary tubes. Leak Lock is a good way to lubricate the bearing surface of a flared joint as it will not contaminate the refrigerant. We are not talking about buttering it like your toast.

    All these recommendations of using double flares for a standard or long SAE flare nut is not correct. First off copper is only for single flares as it cannot handle the fold over and will just crack on the larger OD lines, second the double flare nut is an inverted nut meaning it has the male threads and the recieving end has the female. Each flare requires specific contact area and bearing surface area. Each flare has its specific nut to accomplish this and can be specific to the material being flared.

    And 500 microns is not even that anal, Mitshubishi recommends 200 microns for one hour for their units. I too remember when 28"Hg was good to go, many people have not been educated in the new refrigerant requirements. R134A is NOT as "touchy" as R410A and does not require the same surgical precision of evacuation.




    What a fountain of mis-information!

    You clearly stated that flared connections are untrustworthy and that they should be cut off and brazed. Hence, my question about replacing the service valves with sweat ones was quite reasonable.

    Where do you come up with the reasoning that a brazed joint is one joint, but a flared joint is two? Both have two surfaces that are joined together: one by fusing the two with an alloy, the other by using the pressure created by the torque of the flare nut.

    You also seem to be confusing an inverted flare with a double flare. A double flare does not use a male flare nut.

    Your statement about copper being unusable for double flaring is totally erroneous. I've been doing it for nearly twenty years without cracking and leaking on everything from low temp refrigeration to mini splits, oil lines, gas lines and more. Many of these systems I go back and service for years and I've never seen a leak. You're theorizing, not speaking from experience. Or else you simply don't have a good flare tool or lack the skills to make a good flare. Do you own a good double flare tool? If so tell me how many times you've used it on copper and the copper cracked and I'll tell you that you don't know how to flare properly.

    Mini splits do indeed have capillaries, not as the expansion device, but in the distributor tubing as well as on the reversing valve. The manufacturers clearly teach in their training classes that this is the reason they use flares is because they know that most installers won't use nitrogen when brazing and they don't want those tubes getting the particles of oxidation in them.

    LeakLoc is a sealant, not a lubricant. It should never come anywhere near a flared joint.

    Maybe you should run your theories by some of the manufacturers and see what they think. I'm not buying them.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    Harvey RamerHatterasguy
  • Larry_52
    Larry_52 Member Posts: 181
    Ironman,

    No it is not reasonable, it is ridiculous. Evacuating a system to cut off a brand new service valve and add a new one is ridiculous.

    My communication was at fault here. I was talking about any splice connection versus flared splice (flared splice being two connections).

    An inverted nut for a flare is always for a double flared tube. So the majority of double flares use a male flare nut, look at your brake lines.


    My statement was not erroneus. Copper tube must be annealed or made annealed prior to a double flare or it will not work. All twenty years of experience and you never once came across hard copper on a refrigerant line? Find a single publication that recommends a doube flare for copper tube, you will not. The whole ramble about flare tools is erroneous. Yes I own flare tools, and yes I use them. I have found and myself cracked steel, stainless, aluminum and copper while flaring. At this point in my life I know when to expect them and based on the context of the situation have taken chances. Telling me twenty years of perfect flares is all you have ever done is just not true. It would be like if I said I have never had a bad brazed joint or weld.

    By your input am I supposed to believe no one is allowed to braze anymore? Statements like these, including the start of this paragraph, are pointless. The fact is a large portion of hvac installers do install their units with brazed joints and they know all about N2. My point is valid, brazing splices and evap connections are permanent and provide less leakage possibility.

    Thanks for the tip on leak lock I was adding it to my crankcase all this time. But using it on the backside of the bearing surface of the flare and threads it will lubricate the joint when tightening.

    Heck, even water is used as a lubricant...
  • Techman
    Techman Member Posts: 2,144
    Stenty, be aware that all nitro 's are not the same. Some are what we are "supposed to use",that being the "dry nitrogen" version.The other version "not-dry nitro" has moisture in it ,so, why bother to put moisture into the AC system ,then turn around and remove the moisture w/ the vac pump?!?!
  • icesailor
    icesailor Member Posts: 7,265
    Is the issue of R410a Flares over the flaring tool? Because if that is so, and Ridgid Tools own the patent to their rolling flare tool that I bought my first one in 1968, Yellow Jacket must be paying Ridgid royalties. Or Ridgid let the patent expire.

    http://www.yellowjacket.com/sites/default/files/Flaring Tool - R-410A vs. Others.pdf

    If you can't make a perfect and unsplit flare every time with the ridged type flaring tool, you need to find another occupation.
  • RobG
    RobG Member Posts: 1,850
    The only problem I have ever found with a flare is when I start daydreaming and forget to put the flare nut on BEFORE I flare the tube.
    Harvey RamerKC_Jones
  • Tinman
    Tinman Member Posts: 2,783
    Been there, done that, bought the t shirt.
    Steve Minnich
  • icesailor
    icesailor Member Posts: 7,265
    I've done that. More often, I had the flaring tool in an od place and I don't have the tool centered on the indent on the block. When all done, the flare is off center