Repair Frozen Pipe with Soldering

When working on frozen pipes, pay attention to the cause of the freeze. Are the pipes too close to an exterior wall, or is there a tiny crack in the exterior wall that allows a draft of cold air to blow on the pipe? Be sure to insulate to keep cold air away from the pipe, but do not insulate between the pipe and the warm house. Copper pipe leaks

This job is a pain, so prevent it from happening again. Using a heat tape is only a temporary solution. Insulation and protection is the permanent fix.

If you can’t find the time to do it right, when will you find the time to do it over?

Galvanized steel pipe with leaks often require cutting out the damaged area, then using a union to connect the new section with the old one. A union is a split coupling that allows pipes to be connected from two different directions.

Copper pipe leaks are easier to correct because joints are inserted together, then soldered with a torch using lead-free solder and rosin flux.

Quite often customers come into the hardware store needing a fitting a little larger than the standard copper size. This is because the ice in the pipe expanded the copper to a slightly larger size. Unfortunately there are no oversized couplings, so the damaged, oversized copper piping must be cut out for a coupling to fit.

Prepare the area for soldering by first opening all faucets that are before and after the damaged section to drain out all the water. If a little water keeps appearing out of either end of the pipe, you can use crustless bread balls shoved into the pipe to absorb the water while you are soldering the joint together: they dissolve when the water is turned on. There are also special water plugs you can purchase to shove into the pipe to stop the dribble of water.

Make sure to sand the pipe and fittings to remove all oxidation and dirt before using bread or plugs because you do not have much time before the water dissolves them. Even a little water in the pipe will dissipate enough heat from the torch to prevent the joint from being soldered properly. This can make you crazy.

Prepare the copper and fitting by sanding both surfaces with medium emery paper until the surface is shiny and clean. Once the parts are sanded, do not touch them with bare hands because oil from the skin can ruin a solder joint.

Coat both surfaces with rosin flux and assemble. Using the torch at medium flame heat the fitting until the solder runs between the copper and the fitting. You only have to apply the solder at one point between the fitting and the pipe. As the solder melts, capillary action draws the solder everywhere between the fitting and the pipe. Look for a silver ring all around the fitting to be sure the solder did flow all around the fitting.

Once the areas are soldered, you can reheat the pipe to wipe the excess solder off the pipe and fitting.

When I am in a tight spot where I really do not want to chance a leak, I will reheat and re-solder the joint a second time.