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Tried running 5 and 5 with my rig rather than 7 and 14 and it was so much easier to control. Thanks guys.

Originally Posted by eddiegoodfellar

What pressures are you guys setting your regulators to?

For oxy-acetylene I usually do about 5 and 5.

Old debate, I was a Welder before being a HVAC Tech (Company Owner) soooo you know what my opinion is. I use a Turbo some times but I personally like the Oxy-Act. best. I almost see the Turbo torch as a small Rosebud!

yes, reg. pressures should be equal. that is supposed to create a "clean" burning flame.

as far as high heat, low heat, if I'm doing TXv's, etc., I wan the highest heat possible, so I can be in and out as quick as possible.

I purchased a new kit yesterday. I phoned one of our construction guys to ask where to set the pressures and he said 7psi and 14psi. I guess he read the book you mentioned.

I myself have only use an oxy-acetylene rig, but it is heavy to carry up a ladder to a roof. And I go through tanks very quickly. There are Victor Turbo Tourch tips and Harris Inferno torch tips that easily put out enough heat to braze 2" tubing with air-acetylene. All that is needed is an MC acetylene tank. I believe the correct air-acetylene tip will put out as much heat as an oxy-acetylene rig, and work just as fast.

Here is an urban myth. I suspect this myth originated from an a/c textbook called Air Conditioning and Refrigeration Technology. This book claims oxygen should be set at 14psi and acetylene should be set at 7psi. This is not correct. This would only be the case for cutting metal, not brazing or welding metal.

Both oxygen and acetylene should be set for the exact same pressure on regulators. If the oxygen is set at 5 psi, the acetylene should also be set at 5 psi. The exact psi setting is determined by the manufacturer of the tip. Every tip should come with a spec. sheet that tells you what pressures should be set on the regulators. If you don't have this sheet, go to the respective manufacturer's web site with the tip size you have. You should be able to find the information there or by calling the manufacturer. I think I was wasting a lot of oxygen by having the oxygen on my regulators set so high.

This information comes from engineers at Harris, Victor, and Uniweld--the three largest manufacturers of welding equipment.

The actual flame should be a slightly carburizing flame, never an oxidizing flame.

What pressures are you guys setting your regulators to?

I changed an evaporator in an ice machine today. With my oxy/acetylene and #2 tip I did not burn any wires or insulation. No burn marks whatsoever, you can't even tell I was in there. With a turbotorch I would have burnt everything for sure.

I have a friend who uses air acetylene for doing resi but in commercial I wouldn't think of wasting time with that. Oxy acetylene for me. I use a dual tip for anything over 7/8. Makes quick work of sweating out compressors.

Stay-Brite, or not...

Hey Frank, This topic might be worthy of its own thread...

Originally Posted by Frank Truth

Low temperature silver solder like Stay-Brite 8 has many advantages for all residential connections except those made directly to the compressor. Above 250F Stay-Brite 8 quickly weakens. Residential system fittings should never get that hot except at the compressor fittings.

You don't have to seep anhydrous nitrogen when using a low temperature solder. According to Harris Products, Stay Brite 8 produces a stronger joint. They say that high temperature brazing anneals and weakens cooper tubing. That annealed cooper will burst at a lower temperature.

According to Guide to Brazing and Soldering, a brazed joint with silver solder will burst at 1,800 psi, while a Stay-Brite joint will burst at 3,800 PSI. See page 19 where they show a picture of a Stay-Brite joint that held-up in the same copper tube that caused a brazed joint to burst.

If you use Stay-Brite 8 do not flux the innermost half of the joint to prevent flux from entering the system.

Moreover, low temp. soldering is safer for a/c components like TXVs, reversing valves, and filter dryers. There is less chance damaging these components.

"Both Stay-Brite and Stay-Brite 8 produce an overall component with greater strength than a brazed component whose base metals are weakened by annealment from high brazing heat. Stay-Brite solders bond with all of the ferrous and nonferrous alloys. Joints soldered with Stay-Brite solders exhibit considerably higher than necessary elongation for sound, dissimilar metal joints and vibration applications."

Stay-Brite 8 can melt in a fire and release refrigerant. That is why Stay-Brite 8 should not be used in commercial applications. Also, many companies will void their warranty if their systems are not brazed in place. They fear overuse of flux will contaminate their systems.

However, there are techs here who feel differently.

"If Sta-Brite was a superior method you would see it used in the equipment you install. If the IOM paperwork said to apply flux and Sta-Brite to the joint I would do so without question. The bottom line is that it requires acid to prepare the copper . It also produces debris into the piping as it is applied ( beads ). And the "strength," the argument is that the lower melting point does not anneal the copper and that it is 'STRONGER,' BS. It is a brittle connection that will fail as vibration over time takes it's toll on a material barely hanging on from new. Yeah, sometimes it worked with R-22 but with 410-A it is even further from being an acceptable method of joining pipes and components."

I believe air-acetylene with a Turbo torch tip should get hot enough for any job. Victor Turbo Torch and Harris Inferno make different air-fuel torch tips for different size tubing. You can't use the same tip on 5/8" inch tubing and 2" tubing.

Low temperature silver solder like Stay-Brite 8 has many advantages for all residential connections except those made directly to the compressor. Above 250F Stay-Brite 8 quickly weakens. Residential system fittings should never get that hot except at the compressor fittings.

You don't have to seep anhydrous nitrogen when using a low temperature solder. According to Harris Products, Stay Brite 8 produces a stronger joint. They say that high temperature brazing anneals and weakens cooper tubing. That annealed cooper will burst at a lower temperature.

According to Guide to Brazing and Soldering, a brazed joint with silver solder will burst at 1,800 psi, while a Stay-Brite joint will burst at 3,800 PSI. See page 19 where they show a picture of a Stay-Brite joint that held-up in the same copper tube that caused a brazed joint to burst.

If you use Stay-Brite 8 do not flux the innermost half of the joint to prevent flux from entering the system.

Moreover, low temp. soldering is safer for a/c components like TXVs, reversing valves, and filter dryers. There is less chance damaging these components.

"Both Stay-Brite and Stay-Brite 8 produce an overall component with greater strength than a brazed component whose base metals are weakened by annealment from high brazing heat. Stay-Brite solders bond with all of the ferrous and nonferrous alloys. Joints soldered with Stay-Brite solders exhibit considerably higher than necessary elongation for sound, dissimilar metal joints and vibration applications."

Stay-Brite 8 can melt in a fire and release refrigerant. That is why Stay-Brite 8 should not be used in commercial applications. Also, many companies will void their warranty if their systems are not brazed in place. They fear overuse of flux will contaminate their systems.

However, there are techs here who feel differently.


"If Sta-Brite was a superior method you would see it used in the equipment you install. If the IOM paperwork said to apply flux and Sta-Brite to the joint I would do so without question. The bottom line is that it requires acid to prepare the copper . It also produces debris into the piping as it is applied ( beads ). And the "strength," the argument is that the lower melting point does not anneal the copper and that it is 'STRONGER,' BS. It is a brittle connection that will fail as vibration over time takes it's toll on a material barely hanging on from new. Yeah, sometimes it worked with R-22 but with 410-A it is even further from being an acceptable method of joining pipes and components."

This advice as to which is better Victor Turbo Torch or Harris Inferno?

"You should also check out the INFERNO line from Harris. I have a turbotorch and after demoing the Inferno set, I can tell you they have much better torch heads. They don't get hot, the flame is concentrated straight ahead, right were you want it. I want to sell my turbo for the Inferno, now."

Please don't link to other forums

If ya ever have the pleasure of replacing a Middlby Marshall pizza oven blower motor. You will definitly be happy with oxy/acet with the cutting tip.

Originally Posted by 2sac

oxy/act for me

same here, extra tanks are a must. And I have cut off a shaft or two with em.

I prefer oxy/ace its exact, for tight places, and leaks. I find the turbo torch to hard to use outdoors and indoors in tight places. I don't know what tips it was because it wasn't mine.

Originally Posted by cobra2411

... take a little time and learn how to set the mixture. Start with gas then add in the oxy. You'll see the cone sharpen up and there will be a yellowish outer cone, a blue middle cone and a white inner cone. Keep adding oxygen till the yellow cone disappears into the blue cone. I like to set mine so there's a slight wisp of yellow visible around the outside of the blue cone.

... Devil is in the details, these'll get you there.

ive only run Btank but want to try oxy. seems like it would be better.

at home I break out the oxy to heat a stuck bolt, need to see if work will pay for it

Oxy for me, I have a B-tank for heating work.

I carry a turbo torch for "everyday use" and only drag out oxy/ace from our shop for specific projects (maybe once a year).

oxy/act for me.

I'm into old cars and had the blue-tipped wrench around anyway, so it was natural. I've got one of the small portable ones with the plastic carrier. I work residential only so the #2 tip is there all the time.

If you do make the switch, take a little time and learn how to set the mixture. Start with gas then add in the oxy. You'll see the cone sharpen up and there will be a yellowish outer cone, a blue middle cone and a white inner cone. Keep adding oxygen till the yellow cone disappears into the blue cone. I like to set mine so there's a slight wisp of yellow visible around the outside of the blue cone.

Many many years ago I worked for a co that only used b tanks...... I thought they did a fine job...... Ive also used mapp gas years ago when I didnt want to drag a b tank or oxy acetelyne outfit into an attic....... But Ive always preferred oxy acetelyne.....

My last oxy acetelyne set had this wore out tip on it..... I could use that thing on anything from cap tubes... distributor heads.....all the way up to 2 and 3/8 pipe...... same tip......lol

Nobody else could use that torch...... they would burn holes in stuff with it... I used that torch for over a decade...

I think everyone should just move on up to oxy acetelyne......get a selection of tips or get a big reamed out and wore out tip and just learn to use it.

I have two old mapp gas heads that I use for my coffee can forges.....and recently I saw a two burner mapp gas head that I am thinking of buying for a coffee can forge...... twice the heat of one torch and you only have to worry about keeping one can of mapp gas...or whatever they call it now......from exploding...

sorta went off topic...... but my mind has recently begun to bend on its own...... I may not even be aware that I am posting this....