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  1. #1
    Join Date
    Oct 2009
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    Rhode Island
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    120

    Thumbs up using C02 instead of Nitrogen??

    is this okay to do, we do not carry nitrogen but have C02 i was just wondering if since they are both inert gasses can i run c02 while brazing??

  2. #2
    Join Date
    Sep 2008
    Location
    Western PA
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    25,670
    I have used both and have yet to see a difference.

    CO2 will tend to have a bit more moisture in it unless you buy BONE DRY grade CO2.

  3. #3
    Join Date
    May 2011
    Location
    San Antonio, TX
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    34
    Co2 is not inert.

    Co2 + H2O = carbonic acid. If there is any moisture in the system you are forming acids in there.

    http://en.wikipedia.org/wiki/Carbon_dioxide

    HVACR isn't cheap. This field has more specialized and expensive tools than most others. Some you can get along without, some you can't.

  4. #4
    Join Date
    Sep 2008
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    Western PA
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    Quote Originally Posted by clearchris View Post
    Co2 is not inert.

    Co2 + H2O = carbonic acid. If there is any moisture in the system you are forming acids in there.

    http://en.wikipedia.org/wiki/Carbon_dioxide

    HVACR isn't cheap. This field has more specialized and expensive tools than most others. Some you can get along without, some you can't.
    Technically, Nitrogen isn't inert, either.

    Ever head of Nitrous Oxide?

    Once you remove the moisture (EVACUATION) your carbonic acid goes away. Carbonic acid REQUIRES moisture to be an acid.

  5. #5
    Join Date
    May 2000
    Location
    Rochester, NY, USA
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    14,305
    before we go any further let me get a bowl of

    ok, you may continue.......

    oh and it really doesn't matter which you use. However IT'S MY PERSONAL OPINION that you should NOT use CO² on a R-410a system. *N* is much drier and it will work better.
    The Last four letters


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    any questions

  6. #6
    Join Date
    Oct 2009
    Location
    Rhode Island
    Posts
    120
    so the answer is yes its okay to use c02 while brazing but Nitrogen is best?

  7. #7
    Join Date
    May 2000
    Location
    Rochester, NY, USA
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    14,305
    Quote Originally Posted by RIGUY View Post
    so the answer is yes its okay to use c02 while brazing but Nitrogen is best?
    correct
    The Last four letters


    American = I Can, Republican = I Can, Democrats = Rats


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  8. #8
    Join Date
    May 2011
    Location
    San Antonio, TX
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    34
    Quote Originally Posted by jpsmith1cm View Post
    Technically, Nitrogen isn't inert, either.

    Ever head of Nitrous Oxide?

    Once you remove the moisture (EVACUATION) your carbonic acid goes away. Carbonic acid REQUIRES moisture to be an acid.
    Well, yes, but the pathway to NO isn't usually directly from n2. I'm not a chemist, but there's probably levels of reactivity.

    Also true, you take away the h2o and there's no acid. But isn't it the case that acid + oil -> nasty organic acids? To read the HVACR literature any acid in the system is reason to dump the oil, change your filters, add acid remover, sacrifice a newborn calf and generally freak out.

    Quote Originally Posted by jmac00
    before we go any further let me get a bowl of
    Hey, my first bowl of popcorn! Extra butter on mine plz!

  9. #9
    Join Date
    Jun 2011
    Location
    Southeastern PA
    Posts
    61
    Lol I was carrying a tank of 22 today into an apartment to charge the system and a lady asked me what I was using helium for?

  10. #10
    Join Date
    May 2000
    Location
    Rochester, NY, USA
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    14,305
    Quote Originally Posted by Carbonite View Post
    Lol I was carrying a tank of 22 today into an apartment to charge the system and a lady asked me what I was using helium for?
    did you tell her it was to make the bong work better
    The Last four letters


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  11. #11
    Join Date
    May 2000
    Location
    Rochester, NY, USA
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    ok, lets get technical

    Inert gas (Noble Gases) are in the 18th column of the periodic Table (the whole right side of the table) These include helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and the radioactive radon (Rn). There is one more but no one can spell it.

    The Gases are completely dry (devoid of moisture) However, Argon is probably the best of the Noble Gases for welding. If your welding (TIG or MIG) stainless steel tube, you would use argon in the tubes and not nitrogen. Argon is relatively expensive compared to Nitrogen.

    But what are we really after here. All we want to do is displace the air in the refrigerant tubes. But we want to do that with *dry* gas, to avoid long vacuum times.

    What it boils down to is expense. Nitrogen is very close to the Nobel Gases, but it does the job at reduced over all costs, but CO² is even cheaper than Nitrogen.

    so choose your gas, but like I said I would use Nitrogen on any R-410 systems
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  12. #12
    Join Date
    Apr 2009
    Location
    in a garage
    Posts
    46
    I remember using N to pressurize lines while brazing to prohibit scale and oxidation of the copper during brazing. not sure what moisture has to do with it. Its the O thats corrosive..
    as far as usng co2 , it may still reduce oxidation but
    since it has an oxide component, not as well, eh.

  13. #13
    Join Date
    Jun 2010
    Location
    northwest connecticut
    Posts
    60

    ????

    I thought that as well your trying to displace oxygen also to reducing the oxidation scaling on the inside of the pipe.????

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