How to sweat a copper pipe – Sweating pipe

Sweating pipes is easier than you can think and it is a DIY(Do It Yourself) process. With the right tools and precision, sweating a copper pipe can be done in no time. It is not difficult but it takes practice.

Steps: Soldering Basics

    1. Cut the pipes: A clean cut makes all the difference. Use the correct cutting tool and lodge it tight around the pipe to get a clean and perfect cut. A tube cutter or a hack saw can be used, but tube cutter gives a cut with less burs.

    1. Clean the edges: Wipe off the cut edge to remove any burs. A wire brush would be the preferable tool to clean the bare metal inside the pipe. If you use a hack saw, a filing tool is required to remove the extra burs. The outside can be cleaned using a sand paper or a cleaning brush, until it attains a shiny surface.

    1. Assemble: The necessary fittings, pipes and joints are to be kept ready. Sweating the pipes one after another without any hesitation is easier as the heat flow will be even and quick.
    2. Flux/ soldering paste: Apply flux around the pipe evenly. This flux can help the smooth spread of solder. Not just the outside but also the insides are to be applied with flux.

    1. Heat: Do not apply heat directly on flux, the blue flames should just touch the pipe and not heat them too much. Apply heat on the pipe after joining the two ends. The best way to determine if the pipe is heated to the soldering temperature is to check by touching the solder on the join. If the solder melts and runs along the join, then it is at the right temperature.

    1. Sweat connection: The soldering is a capillary motion. Once two joints are in its place and the flux has spread evenly, Start sweating the copper fitting. Excess solder will run inside the pipe and clog the pipes. For vertical joins extra care is to be taken to not let the solder inside and be quick in running the solder around the joint.

    1. Clean: Let the solder rest for few seconds and then wipe them with a clean rag after applying some flux while the pipe is still warm. This is to make sure there is no excess solder and applying flux will make it easier to clean.

How to solder copper to brass – The sweat connection

Soldering is technique which involves a metal with lower melting to join a metal with higher melting point. Copper is often used with brass fittings and soldering them involves the use of some tools, they are:

  • Propane or Mapp gas torch
  • Heat shield- To prevent from getting burnt though handling with correct tools should do the trick.
  • A mirror (optional) – Required in intricate work where the other end can’t be seen from the work perspective.
  • Soldering wire- The solder material in wire.
  • Flux- Used to provide a firm solder between copper and brass and prevents the insides from oxidation. Oxidation prevents the solder from sticking to the brass and copper.
  • Cleaning brush How to clean copper pipe – To remove burs. Sand paper will work too, but cleaning brush will do a better work.

Soldering basics: How to solder copper fittings to make the sweat connection

  1. Measure the copper pipe and the brass fittings. None of the fittings should be large or too tight. Correct fit is the first step in getting a neat solder.
  2. Remove the burs using a 3/4 inch cleaning brush. A shiny look on the outside should do. The shinier the better.
  3. Apply the copper pipe ends with flux and even out the application with brush strokes.
  4. Take the brass fitting and screw them down onto the copper. The screwing motion is to let the flux stick to the insides of the brass fittings as well.
  5. Soldering copper pipe: Before soldering the joints are to be heated to a point where the metal glows. Light up the torch and start heating the metals. Move the torch in a way that will help the heat spread evenly. When heated too much the metal starts glowing in a red shade. This would mean you have to let the metal cool down a bit before you solder.
  6. Sweating pipes: Once the correct temperature is been attained, place the solder perpendicular to the joint. This is to let the solder flow into the joint. Touch the tip of the solder wire at the point where the joint is and keep moving it along the joints. The solder wire will melt itself. Follow the path with the torch to ensure it has stuck.
  7. Once all the gaps are filled in with the soldering wire let the metal cool down. When it is still warm wipe off with a wet rag to remove any excess solder running along.
  8. Congrats- You now know how to solder properly and how to solder copper pipe!

How to solder copper refrigerant tubing

Weld copper pipe

How to weld copper pipe? Well you don’t always have to! Soldering implies that copper is soldered with a metal having lower melting point and must be soldered with silver-based components. Refrigeration technicians have reported that a technique called soft soldering can be used to reduce costs. Sweating copper pipe.

Analysing that statement:

  • Soldered copper tubing is installed for refrigeration systems. Solders can be formed with many combinations, Tin/lead and Tin/antimony are not recommended, as they are of less strength. But Tin/silver is a preferable option in order to avoid welding copper pipe.
  • By cleaning, fluxing, and heating a copper plumbing joint we remove any oxidation. Nitrogen is not required to do this, which will reduce the cost in a large scale. The other advantage is that, there is no need to carry the cylinder around with you.
  • On using a Tin/silver to solder the copper pipe we get the advantage of handling a smaller torch with less heat can be used to weld. This implies less weight in carrying the equipment. Another advantage is, less heat means less damage and need to less cautious. The only disadvantage is that they are limited if service temperatures exceed this.
  • Servicing of the equipment is a pain to the user. It is better to follow the instructions and recommendations of the manufacturer. They tend to be conservative in what they recommend and that may be implying to use copper brazing over soldering.

Soldering basics for a sweat connection:

  • Measure the cuts and clean them. Apply flux and spread them but do not apply on the ends, rather rotate the fittings.
  • This action will allow the flux to spread on the inner surface of the fitting as well. The type of flux depends on the type of metal used.
  • Light the torch and move the torch. The movement of the torch is suggested strongly to avoid over heating of the parts. The heated parts will make it easier to melt the flux.
  • Move the flame away from the joint. When the temperature is correct to melt the solder, stop applying heat directly. You are now sweating copper pipe.
  • Continue copper soldering by touching the solder on the copper fitting plumbing joint section, until a ring is formed by the solder material. The silver solder will make joining the refrigerant copper tubing and components a much easier process.

Sweating copper pipes – cure condensation

Sweating copper pipes are the silent killer to your house. Over time the moisture condensing on the cool copper pipe can cause damage in many ways. The condensate can dampen wood and cause structural failure, termites, wood rot, as well as insect and rodent water supply, and finally, even black mold. It can also lead to increased pipe corrosion. Is not easy to get rid of this condensation especially in warmer humid climates.

The warm air hits the cool pipe and the water condenses on the pipes just like a glass of ice water on a summer day. The dew point in the basement must become lower or the basement, must become drier, or the water pipe, warmer.

How to remedy sweating copper pipes?

There are three techniques: insulation, mixing valves, and containment.
The use of foam pipe insulation that is well wrapped will keep the moist air away from the pipe, preventing over or reducing condensation. The method is to wrap the pipe from house entry, throughout the house, including under the sink or toilet. Also in extreme cases and examples the toilet tank itself may need to be wrapped in insulation. There are actually premade toilet tank insulation kits which use Styrofoam of the inside of the tank to warm the temperature of the outside of the tank. Be sure to seal all joints to prevent infiltration.

Figure 2 Insulate to reduce sweating pipes
Mixing valve. Another method to prevent sweating copper pipes is to route a hot water pipe and mix it into the cold water. The hot water tees into the cold water and the mixing valve mixes the two temperatures to produce warm water. The warm water being warmer than the moist air prevents condensation. The mixing valve is adjustable and enables the fine-tuning of the temperature . Optimally, the mixing valve will be adjusted during the four seasons to minimize condensation and minimize the use of warm water. The mixing valve should be installed for the whole house close to the point of pipe entry into the house. Most houses use three-quarter inch incoming water supplies, therefore the mixing valve would have to also be three-quarter inch on all three legs: the two inlets and warm outlet.

How to solder copper pipe

Copper pipes play the key role in the supply of water, both hot and cold, and as a refrigerant line in the HVAC systems. Sweating copper pipe is joining two plumbing joints using a filer metal, either the same as that of the pipe or some other, which has a lower melting point. This forms a permanent connection.

How to solder pipe:

It is a simple process that could be done at home. The complexity level for soldering a copper pipe is simple. To obtain a perfect solder, selection and usage of the materials used are important.

Torch– Flames and their force determines the perfection of soldering a copper pipe. The flame shapes are different, for instance take the cone shaped flame, it concentrates on one particular spot whereas the rose bud shaped flame will wrap the pipe and will even out the temperature. Self-lighting/Auto start torches are safer and easier to use. Normal torches would require lighting and relighting often involving extra worry about burning down yourself or the place.

Cleaning brush– A clean pipe will have a neat finishing. Make sure you clean the ends of the pipe with any abrasive material. This is to make the soldering strong.

Flux– Before soldering apply the flux on the ends of the pipes. Flux helps in even spreading of the solder into the joints.

How to solder properly:


  1. Assemble all the pipes and copper fittings to be joined. Meddling with pipes after lighting a torch is dangerous and would result in unclean soldering.
  2. Flux the joints evenly. Right amount of flux would do the job itself.
  3. Light the torch and heat the plumbing joints evenly.
  4. Soldering Copper: Place the solder 90 degrees to the plumbing joint and rotate the joint slightly to let the solder spread. With the right amount of flux and heat the solder will flow and fill the gaps.

Things to be careful about: How to sweat copper pipe


Heat level: Over heat would burn the ends and leave a black burnt mark on the pipes. Under heating would not let the solder flow evenly rather making them get logged evenly.

Application of flux: Spread it with smooth motion. Do not dab.

Torch level: Make sure the flames are about 1-2 inches. This is easier to hold at a position to apply proper heat.

Move to next joint: As soon as you finish one joint move along to the next joint. The heat from previous would help in making the work easier if the joint is a subsequent one. This is how to solder pipe.

Touch: Touch the flame to the copper pipe every second to get a better flow.

How to solder copper pipe in China

Copper pipes are more usually utilized in plumbing then most other alloys due to they are very less likely to corrode. Well you can know how to sweat copper pipe in China successfully. In this information about soldering a copper pipe you may find why you might have failed prior, and how to accomplish.

The method of soldering copper in China is a little scary.

On Saturday, September 26, 2015, 13:49, The reported the following ”Soldering materials which connect pipes were officially confirmed to be the main reason for excessive lead in the drinking water of 11 public housing estates for the first time.”

In fact the lead levels in the water where 585 times the allowable levels when compared to Britain. Hmm, next time in China I guess I’ll drink the bottled water, right !

Now we know not to use lead solder!!! Use tin silver solder instead.  Lets get to the sweating pipes and soldering copper pipes.

The right flame  – How to solder pipe

The initial tip is to utilizing the proper blaze for the task. The blaze which is right to solder copper pipe joints is the “rosebud” blaze. A cone structured blaze puts lot of heat at one spot it reaches. A rosebud blaze wraps the pipe in flame, bringing the whole joint to the proper temperature at the same period.

You are attempting to apply solder to a point where a pipe enters the fitting, to enable the solder run into a joint by capillary action. To make this you need an even temperature across the whole joint. Your rosebud blaze will free you to put the solder at correct moment rather than forcing you to have that blaze moving which plays devastation with your timing.

Copper soldering basics – How to solder copper fittings.

How to solder copper pipe in China in three easy steps without lead(!!!):

  1. Begin with a little blaze, just large sufficient to go most of the manner across the pipe.
  2. As the pipe gets heat up, touch the corner of a solder to the joint at 90 degrees from source of the blaze. That maintains the solder from melting off in blaze.
  3. Touch it there each second or so till it moves into the sweat connection joint.

If you’ve made this right the solder will go across the joint and meet at other end mostly by itself. For bigger pipe sizes you might need to move a tip of a solder along a joint face. You might be able to extract the blaze and feed solder to yet hot joint. It’s always good to underneath-heat than to over-heat when soldering.

As early as you’ve ringed a joint with the solder, then shift to the next corner of fitting. Subsequent sides must go quicker having already attained heat from the first work. Don’t wipe a joint or jiggle it in any manner till it gets set. You’ll notice if you see which the solder goes from very silvery to just vivid. As early as this dulling happens the solder has set.

If a fitting glows and turns to “rainbows”, you’ve utilized too much heat. Allow it to cool, cleanse it up inner and outer and try again.

I hope the aforesaid soldering tips have helped. Joining copper pipe by soldering water pipe isn’t actually really complex once you have the hang of it.

How to sweat copper pipes with water in it?

Is it possible to sweat copper pipes that are filled with water? Copper pipes filled with water can be soldered only after completely removing the moisture from the pipes. Soldering copper pipes is very difficult in the presence of water. The solder can be applied only on a dry surface. After heating, the solder should be allowed to cool down and get hardened. This process will not go smooth on wet pipes. Prior to sweating copper pipes it is very important to get rid of traces of moisture from the tubes.

The equipment that is required for soldering copper pipes filled with water include gloves, sandpaper, brush, rags, joints, deburring tools, goggles, flux, lead-free solder and torch gun and Plumber’s bread or Jet Sweat.

How to solder copper pipe with water? Make the copper pipes dry.

As the first step, flow of water into the pipes should be arrested. Ensure that water does not enter the tube from any source. As the next step traces of moisture are to be removed completely from the tubes. Plumber’s bread is commonly used to remove moisture from the pipe. The Plumber’s bread is made of corn starch and will absorb the moisture from the copper pipes. Instead of Plumber’s bread, jet Sweat can also be used to remove the moisture from the pipe. Jet Sweat will ensure complete removal of moisture.

Sweating pipes

Once the pipes are 100% dry, the process of soldering copper pipes can be started.

How to polish copper pipe? The edges of the pipe are to be made smooth by rubbing with sand paper or emory cloth. The edges should appear polished and shiny.

A thin coat of flux must be applied around the pipe using a brush. Flux is to be applied inside the fittings also. Ensure to make only thin layer of the flux since too much quantity of flux may facilitate quick oxidization. Wear thick hand gloves and abstain from touching the flux with bare hands. Since flux contains various toxic chemicals it is hazardous to human skin as well as eyes.

After applying the flux, the fittings are to be assembled. Ensure that the fittings are connected properly to the copper pipe and move smoothly.

How to solder pipe: Start heating the copper fitting using propane torch. Always start with low flame and then increase the flame gradually. Evenly apply the flame to the joints. One requires a little practice to use the propane torch to heat the pipe.

When the solder starts to melt keep the tip of the solder on top of the joint so that it starts to melt. The entire surface wrapped by the flux will help the  molten solder flow seamlessly. Slowly wipe off the leftover solder with a wet rag and be very careful while wiping the joints since they will be very hot and fingers may get burnt.

How to sweat copper pipe or tubing:

Copper tubing is used in the supply of water and soldering copper tubes are easy and do-it-yourself process. While soldering copper tubes, the selection of solder, tools and flux plays a vital role.

Selection of tubes: In general the thickness of the tube will increase the diameter of the copper tube by 1/8 inches, that is, 0.125 inches.

Cutting: While cutting a tube it’s better to use a tube cutter to get a cleaner and less burs on the edge.

Joints/fittings: The fittings for the tube should be selected carefully depending on your project.

  • 45 degree joint: this will give a connection turning it 45 degrees.
  • 90 degree: A complete 90 degree joint.
  • Reducing adapters: Used when the tube size changes from wider diameter to a smaller diameter.
  • T and cross joint: Used in branching the pipeline.

Soldering Basics: How to solder pipe…..Soldering ensures the connection between joints and the selection of solder is vital. For water tubing, a lead free solder is required; usually a tin-silver solder gives the best results for your sweat connection.

Steps to soldering copper pipe: How to solder properly

  1. How to clean copper pipe: Clean the tubes thoroughly on the insides as well as on the outsides. Sand paper would do the work for the amateurs and professional plumbers would use a wire brush to remove burs and a cleaning brush to create the perfect bur free and shiny outer rim on the copper tube. This is to obtain a smooth area which will result in no-leak tube.
  2. Flux/soldering flux: Use a brush to apply the soldering flux on the area to be joined. Excess application is agreed harmful, but under coating the flux will not solder the joint/fitting onto the tubes.
  3. Torch: A torch that would give a sharp, blue flame is your weapon. The flame should be in such a way that it doesn’t heat a point but heats up the ring as well. 1-2 inches of flame height is the standard flame size.
  4. How to fit the copper pipe to copper fittings: Fit in the joints in their place and screw them down so that the flux spreads itself on the inside of the joints. Heat up the area and try moving the touch point so that they melts evenly inside.
  5. Sweating pipes: How to solder copper fittings…. Place the tip of the solder onto the hot copper fitting, if it melts and starts to run along the joint in a capillary motion you have attained the correct temperature. Continue soldering the copper tubes till the solder is all around the tube joint.
  6. Wiping: Wipe of the excess solder while the tube is still warm (warm not hot) using a clean rag.
  7. Testing: Flush some water to check for any leakages once the pipes are cool.
  8. Congratulations! You are a soldering pipes master !

How to solder copper pipes in Europe?

Sweating copper pipe

Soldering copper pipe has the same underlying procedure in europe, but has some changes in the copper pipe used.

Countries in US and Australia, there are four classifications of the copper tubing. Whereas in Europe there are only three, Type X, Type Y, Type Z.

  • Type X – They are used in domestic services like Hot and cold water supply, sanitation, heating and other general purposed applications.
  • Type Y- Type Y pipes are thicker when compared to the X, and used in under ground services. The services include gas supply, transportation of hot and cold water and engineering services of general types.
  • Type Z- Type Z is thinner than the others and are used as type X pipes are used but in a lesser rate, given the thickness of the pipe.

Soldering basics – the sweat connection: sweating copper pipe

  1. Please follow the safety suggestions on the main page of this website.
  2. Cleaning copper pipe inside: The tubes should be thoroughly clean on the inside as well as on the outside, isopropyl alcohol works best. Sand paper or a wire brush is used to remove burs and a cleaning brush to create the perfect bur free and shiny outer rim on the copper tube. A smooth area which will result in no-leak tube is obtained.
  3. Flux/soldering flux: Using a brush, apply the soldering flux on the area to be joint. Excess application is fine but under coating the flux will not solder the joint/fitting to the tubes.
  4. Torch: A flame torch that produces a sharp and blue-ish flame is chosen. The flame shouldn’t concentrate the heat to a point but heats up the entire ring as well. 1-2 inches of flame height is the standard flame size.
  5. How to solder copper fittings: Sweating copper pipe. Fit the plumbing joints: Screw them down 1/4 turn so that the flux spreads itself on the inside of the joints. Heat up the area and try moving the flame torch in order to spread the heat evenly across the tube and helps the flux stick to the inner surface as well.
  6. Sweating copper pipe: Place the tip of the solder wire onto the plumbing joint, if it melts and starts to run along the joint in a capillary motion you have attained the correct temperature. Continue soldering the copper tubes till the solder is all around the plumbing joint.
  7. Rag: Wipe of the excess solder while the tube is still warm (warm not hot) using a clean damp rag.

How to solder copper in cold climate like Alaska?


Cold weather or heavy wind is a problem as they to disrupt the work, especially with antennas or roof and wind shelter is awkward to use.

How to solder properly : soldering basics
When soldering in cold weather, the heat you apply on the solder might not be as effective as in a moderate region. To obtain an effective result:

  • Clean and cut the pipes as you would do in normal soldering and make the joints as well. Try to pre-assemble and solder the parts inside shelter as much as possible.
  • As an extra step wrap a aluminum foil over them.
  • The foil layers need not be more than one or two or else the heat transfer would slow down.
  • Now if you apply heat using the torch, you will get a perfect solder even in freezing temperature, don’t worry.
  • On a calm day or while working on thin wires a lighter torch would do the job. But in a cold and windy day or working with a thicker pipe, a blow torch may be required. The new electronic lighter will light in any wind.
  • You can tell it is at correct temperature when the flux burns orange as the flame heats the metal.
  • In Using a torch is the better option but make sure to follow the cut, clean, remove bur and flux the parts carefully. Also use lead free solders.
  • Coax Dielectric handles heat better than others but only in some cases.
  • Another suggestion is the usage of Andrew Heliax on the outside where possible. Andrew connectors need to be heated only on the centre pin and not the entire surface. A connector shield compresses against copper shield which was corrugated.
  • Use short RG213 jumpers on the last few feet on the ends and solder them indoors. Work your way to shelter them outside.
  • A heliax is considerably weightless and better in ladder line.
  • The rest of the process can be done the normal way, i.e. cleaning copper pipes inside and fittings, using a brush to remove burs and flux the outsides as well the insides of the fittings to solder them easily.