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How do you braze copper pipe in HVAC?
How do you braze HVAC?
HVAC Training – Brazing Degrease and clean tubing and parts thoroughly. Fit and support the joints. Heat evenly moving the flame in a figure 8 motion. Wait for the flame to turn green in color. Apply the brazing rod to the joint. Do not melt the brazing rod with the torch. Cool the joint.
Can you solder copper HVAC lines?
In HVAC when we’re running copper lines we’re never going to need the strength a weld provides. A brazed joint will always be sufficiently strong. In many situations a soldered joint will be strong enough for what you need. In some situations brazing will be too hot for the job and you’ll have to solder.
Which is the best material to use on HVAC pipe brazing?
When brazing copper the best choice is always sil-phos. Only use silver braze on the brass and steel joints. This compound is very expensive so it is not commonly used when sil-phos can be used.
Do you use flux when brazing AC lines?
When brazing copper to brass or to steel a flux is always required. A flux is also required when using high silver braze alloys like Safety Silv® 45 or 56. Brazing fluxes contain 15 – 35% water so we want to keep excess flux from inside the lines.
Do you need flux for brazing copper?
Remember that copper to copper brazing does not require a flux. Here are a few common combinations: Using Stay-Brite® Solder – Stay-Clean® Soldering Fluxes.
What brazing material is mainly used for connecting copper to copper?
Air-acetylene – This gas has a flame temperature of around 2700°F (1482°C). This type of brazing requires a cylinder of acetylene gas and incorporates atmosphere air to produce the torch flame. Air-acetylene is primarily used for copper-to-copper, copper-to-brass and copper-to-steel joints.
Is it OK to solder AC lines?
It’s okay to solder copper tubing for some of the lines in an air conditioner. Other A/C lines contain high pressure and need brazed or welded joints. Some copper air conditioner tubing has contracted and expanded ends that fit together for joining.
Can you use silver solder on HVAC?
But, did you know low-temperature tin/silver solders have higher strength and ductility than typical plumbing solders? This makes them suitable for most residential HVAC connections. The low operating temperature of tin/silver solder does not overheat the tube so it retains its strength.
Can you braze copper pipe with MAPP gas?
We use MAPP gas with a shield attached it is quite good up to 7/8 copper tube only and the braze joint needs to be away from any large mass of metal as the heat can be drawn away just as fast as you apply it.
Is MAPP gas hot enough to braze?
Mapp/air is hot enough to do silver brazing but common brass brazing is a problem because you cannot heat things hot enough quick enough. Enter oxygen, 100% oxygen rather than 20% oxygen (air) and the flame temperature rises and the heat output rises and not only can you braze but you can actually do a little welding.
Which gas is used for brazing of copper pipes?
Braze-A-Gas consists of oxygen and acetylene that, when combined, are the engineer’s best choice for brazing copper tubes together in refrigeration and air-conditioning systems. These products produce a flame temperature of about 3 500°C, which is significantly hotter than propane, propylene, or MAPP gas.
Can you braze with propane torch?
Brazing permanently joins two metals using a torch. You can use a propane torch to braze most metals you want to join. Propane torches are widely available in your local hardware stores, plumbing supply houses as well as at metalsmith and jewelry supply companies.
Why are copper fittings cleaned before soldering or brazing?
It cleans the metal making the solder stick to the fittings and pipe better it cleas oxides and oils. The longer that copper is kept at the higher brazing temperature, the greater the formation of copper oxide, and nearby valves may be overheated. Why is it important to heat braze joints as quickly as possible?.
Which torch type would be the best choice for a brazing project?
Bernzomatic Torch – This torch features a long hose and trigger ignition that gives the best performance when brazing or soldering, even in those hard-to-reach spaces. Unlike its shorter counterparts, the 5-Foot hose allows for maximum accessibility and mobility during any project.
How hot does it need to be to braze copper?
In actual practice for copper systems, most soldering is done at temperatures from about 350°F to 600°F, while most brazing is done at temperatures ranging from 1100°F to 1500°F.
How do you braze without flux?
You can join copper to copper without flux, by using a brazing filler metal specially formulated for the job, such as Handy & Harman’s Sil-Fos or Fos-Flo 7. (The phosphorus in these alloys acts as a fluxing agent on copper.).
What is the temperature for brazing?
Brazing uses filler materials that have melting temperatures of 450°C or higher; and soldering uses solders (soft filler materials) that have melting temperatures below 450°C. A method of welding that uses filler materials while melting the base material as little as possible.
Which gas is used in brazing HVAC?
Most HVAC installation instructions require flowing nitrogen through the copper tube during brazing. This is an important step in producing a quality HVAC system.
