By Gene and Katie Hamilton
Before You Begin
These instructions are for repairing frozen copper or plastic water pipes. To begin,
find the main shutoff valve near the water meter and turn off the water supply. Then
go throughout the house and open all the faucets so when the pipe is unfrozen the water can flow through the pipe and melt the rest of the ice. Then clear the area around the pipe. If the pipe is inside a cabinet, remove everything to allow plenty of space to freely operate a heating appliance. You may have to cut away some drywall or wallboard to reach a frozen pipe. If that's the case, cut away as small an area as possible.
Step 1 : Heat the pipe
Use a hair dryer or heat gun to warm the pipe where the water is frozen. This can take minutes or hours depending on how hard the freeze and how large the block of ice formed inside the pipe. Use the heating appliance at a low setting. Keep the nozzle moving and be careful not to ignite any surrounding surfaces. Periodically stop and listen to see if you hear water dripping. Let the water flow at the taps after the ice block is loosened to remove any buildup of minerals or residue that may have come loose from the inside of the pipe.
Step 2 : Cut a burst copper pipe
Use a tubing cutter to cut out the section of ruptured copper pipe. Allow for at least a 1/2-inch on both ends of the split in the pipe. Then measure the section and cut a replacement section of pipe.
Step 3 : Solder on the new section
Use emery cloth to clean the ends of the pipe and inside of the slip coupling. Apply flux to the pipe ends and inside the slip coupling. Slide the slip coupling on each end of the new section of pipe, then put the pipe in position and slide the slip couplings on to the ends of the existing pipe. Apply heat to the coupling from below and hold the solder above it.
Step 4 : Repair a plastic pipe
Cut out the ruptured section of pipe with a hack saw and cut a replacement piece to fit. Then join the new pipe to the existing pipe with couplings and plastic pipe cement.
Step 5 : Insulate the pipe
Use foam insulation sleeves to protect exposed pipes or those susceptible to freezing. You can also wrap the pipes in fiberglass strips. Insulation alone will not prevent the freezing of a pipe that has a long run through unheated areas unless water flows through the pipe once in a while.