Braze or solder copper refrigerant lines to fittings

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It seems like the two primary methods for connecting copper to copper refrigerant lines to fittings are either Sil Phos 15 brazing rod or Stay Brite silver solder.
I've done gas welding and some plumbing soldering jobs but would only rate myself as a novice.
Which method is easier for a novice to do reliably? (Sil Phos or Staybrite silver solder.)
I plan to do lots of practice on scrap copper pipe and fittings until I'm proficient. I'd like to know which method is easier to learn and do reliably so I have a good starting point.
For brazing copper lines (3/8 to 1-1/8" in diameter) what oxy/acet tip do you prefer to use. (small rosebud??) Will a Turbo Torch w/ #4 tip and MAPP gas braze using Sil Phos 15? What about the Quick Braze?? Is it worth getting??
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For the novice the silver solder is the better choice. If you don't have nitrogen then you will create a fair bit of oxidation inside the lines if you braze. It has to be a good joint as the high side has a lot of pressure.

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I was mentored on Sil Phos and had no problems with it. Make sure everything is very clean and be sure you have the proper flux. Turbo torchs worked fine for me. I was taught to have a slightly rich flame when using acetylene (no excess of oxygen). I don't know it this it the proper way, but it was how I was taught by an old timer who was self taught, and correspondence schools, in the late thirtys. Beware, when the flux melts and runs one can mistake it for Sil Phos..
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Bubba
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Its simply a matter of personal preferance and what your were "raised" with. My personal preferance is Silphos 15 for copper to copper (no flux), 45% silver w/flux for copper clad(plated) and brass. I use oxy/acetylene exclusively, #2 tip for up to 7/8in, and a small rosebud for 7/8in and larger. For gas welding steel I use oxy/acetylene with a #3 tip up to 3/16in thick, and a cutting head for up to 1/2in thick.... and no, I don't use coat hanger wire for filler rod.
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I did assume that you are doing this on your own equipment when I recommended the silver solder. If you are pursuing a career in hvac then you should learn to braze with mapp gas and with oxy/acet.

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I've done both, and consider Stay-Brite 8 to be easier to use. Zinc oxide flux, emery cloth (not in that order). Mapp torch works nicely, the self lighting kind are very convenient.
The couple times I did brazing, it was 15% silver content sticks, using acetylene and a turbo burner tip.
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Just use a flaring tool and flared fittings. No need for brazing or solder.
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henny wrote:

Straight propane will work for sil phos. However you need to use something like insulating firebrick to contain the heat. And if the parts are large, you may still have problems.
Dan
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siflos is much much easier, does take a little more heat but cleanleness is not as important and you will be able to fill gaps easier it will build up. no question. Ed ke6bnl
copper to steel silver soldier is your choice.
snipped-for-privacy@krl.org wrote:

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You all seem to be split as to which method is easier to learn and more forgiving.
I do have Nitrogen so I'm not worried about oxidation. I also have oxy/acet.tanks and equipment but the thought of using a #2 tip on soft thin copper makes me a little nervous. (my welding skills aren't that great so I doubt my brazing skills will be much better).
I think I'll start my practice sessions using SilPhos 15 and a small rosebud or turbo torch.
Once again I'm simply looking for the method that's most forgiving to a novice for a one time job and that can be readily learned via a few practice sessions. I have no intentions of doing this for a living.
Thanks for the responses.

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henny wrote:

Henny,
I learned a great deal from the people here on how to do this properly. Most of it you can probably Google up..
As for advice... Noone's worked for me best. If you've used oxy/acet at all it's a much better heat source, IMO.
Doing a closed system. ALWAYS purge with Nitrogen. Depending on the line size, I've successfully used 5-15 psi continuously during your job. Pull a Schrader core out and let the gas vent immediately down-stream.
Once done, purge the system for a while and then pull it into a vacuum right away. Leave the system alone for a while and make certain the vacuum holds.
Whatever the gas or liquid in a closed system... do not let things like AIR infiltrate. Whether it's a pump or compressor, it can cause bad problems.
Charge the gas or liquid directly into the highest possible vacuum the system will achieve. This applies to water, oil-hydraulic and gas/liquid HVAC systems all the same.
Some of the guys here might disagree with me here... but it's what should be good practice for learning.
Jake
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I'll second that. Use some silver braze with N2 and oxy-acetylene and a #2 tip. Practice a bit on some scrap. It's not that hard. Remember you're not trying to sweat it in like solder.
The only thing I would differ from what Jake's suggesting is I like to pressurize the system with N2 after brazing. You'll find an occasional leak that won't show up when pulling a vacuum. Plus if you do have a leak you're not pulling air and moisture in.

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cz111 had written this in response to http://www.thestuccocompany.com/hvac/Braze-or-solder-copper-refrigerant-lines-to-fittings-10462-.htm :
------------------------------------- henny wrote:

I was told by a heating and cooling repairman (who has lied to me more than once) and his boss that torch brazing copper tubing does not require the tubes to be cleaned or fluxed because the high temperature along with a 'special silver soder' will eliminate all oxidization, oils, etc... Any comments???
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The 15% silver braze sticks I bought years ago said they were "self fluxing". But, I have never taken the chance that they might be mistaken.
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Stormin Mormon wrote:

Whatttt?? You gotta be kidding. This is for copper brazed AC lines? I do hope you ran some nitrogen through those lines. Dammit Steve, Your Apprentice is running Amok.,
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Stormy doesn't own a N2 kit... remember, his Pinto can't haul much.
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Holy Crap,
What's with all this talk about silver solder, stick solder, Oxy/ACE, yadda, yadda.... That stuff is uh, nice, but certainly not neccessary for 'this' task.
- Score the pipes, fittings outside / inside with steel wool, clean em' off with a dry 'clean rag'. - Fit together parts/joints, flux with water base (non-Acid) flux - Turn on the $10.00 propane torch, heat the joints until the flux discolors , wet the seams really nice with 95/5 solder.
Bob's your uncle....
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That's nice, but technical bulletin # TB 98-04B Dated 11/12/98 states not to use low temp (soft) solder on R410a units. Situation: It causes a jell-like acidic substance that will plug metering devices, strainers, and feeder tubes. Solution: Units must NOT be installed with flux and soft solder. Units MUST be brazed using silver bearing or non-silver bearing brazing material such as sil-fos or plos-copper on all copper to copper connections.
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Man, You're quoting regs from 10 years ago ! You guys sure have some strange regulations down there.... Also, where would the acidity be coming from if you are using a non-Acid flux ? The chemical properties of 95% tin and 5% Zinc SOLDER is 'completely' different than the zinc coating say,.. on the inside/ outside of a pipe ! Companies here have been installing 60 gallon water tanks (1000's of them yearly) the same way with no issues. I can't understand why anyone would use "Copper Phos" (is that what you meant ?) or any stick for that matter on a simple copper to copper connection, and especially a tiny 1/8th connector in a refrigeration scenario.
The only reaon anyone wouldn't use the "Far less expensive 95/5" is because they don't have the skills to keep the pipe and connectors at a constant temperature which is far LOWER than stick or silphos. The application in question just does NOT warrant Stick (silver bearing solder maybe...) but Copper PHosphate and High temp stick ?...... Overkill.
Cheers,
/FC....
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