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.

Leave a Reply

Your email address will not be published. Required fields are marked *