When you think of frozen pipes, you are typically thinking of water supply pipes, not drain pipes. However, drain pipes can freeze, too. If you have a drain pipe in your basement or along an exterior wall, and it suddenly stops draining in winter, there is a good chance this is because the drainpipe is frozen. Here's what you can do to thaw the pipe and address the problem.
Pour warm water down the drain.
The easiest way to clear a frozen pipe is to simply pour warm water down the drain. If the section of the pipe that is frozen is pretty small, this should loosen up the ice and get things moving again. Do not use boiling water; the difference in temperature could be too drastic, leading to a cracked pipe, especially if you have PVC drain pipes.
Use a blow dryer to melt the ice.
If the blockage is larger, simply pouring warm water down the drain may not work. The water may be cooling off faster than it is able to melt the ice. Instead, try using a blow dryer to warm up the section of drain pipe that you think is frozen. This is a lot safer than using a heat gun, since hair dryers do not get warm enough to cause any serious damage. Move the hairdryer back and forth over the pipe. After 10 or 15 minutes of this, pour some warm water down the drain to see if it flows better.
Have the drain cleaned.
Once you have the drain flowing again, it's a good idea to clean the drain. This will ensure water drains through it faster in the future, which will help prevent water from freezing in the pipe again. You can clean the drain yourself using baking soda and vinegar, which will loosen most grime. Or you can call a drain cleaning company; they can use a piece of equipment called a hydro jet to blast the debris out of the drain, preventing future clogs and freezing episodes.
If possible, you should also turn the heat up a few degrees. This will help keep your drain pipes (and supply pipes) from freezing.
Drain pipes sometimes freeze in winter, and this can cause all sorts of headaches. With the tips above, however, you should be able to clear the icy blockage and keep future ones from forming. Reach out to a company that provides drain cleaning services for more information.