Can Hydrochloric Acid Open Clogged Drains?

Hydrochloric acid is not something you want to touch if you can help it. Created by dissolving hydrogen chloride in water, hydrochloric acid is very corrosive. Because it can eat through organic material, it's easy to see why someone might think to clear a clogged drain using hydrochloric acid (or muriatic acid, which is just a slightly less pure variation of hydrochloric acid), but there are a lot of drain-clearing strategies out there, and this isn't a safe one.

If your stainless steel sink drain is clogged with food and you pour pure hydrochloric acid down it, the acid will almost certainly clear out the clog. It might also corrode your steel sink, burn through your pipes, create unpleasant fumes, and irritate your eyes or skin. While pipes made of newer materials may be strong enough to withstand hydrochloric acid, older plastic or metal pipes are more susceptible to corrosion.

Hydrochloric acid is so potent that it shouldn't be used for household tasks unless you've exhausted all your other options and even then should really only be used by professionals, like plumbers, who know how to dilute and safely handle the acid.

Before escalating to using chemical drain cleaners, it's worth trying some simple home remedies for clearing a clog. If the clog is caused by built-up material that has gone into the sink, for example, if you need to unclog a bathroom sink drain that's filled with hair, start by trying to pull it up and out. Cut a length of sturdy wire and bend one end to make a hook or use a simple plastic drain-cleaning tool with teeth attached. Threading the wire or plastic into the drain and snagging the clog may allow you to pull it free. This won't work as well with clogs that are formed by grease or soap scum, however.

Next, try plunging, which creates a vacuum within the drain that may dislodge a clog. Use a sink or drain plunger, which has a slightly different shape than a toilet plunger. Fill the sink with a few inches of water before plunging the drain. If your kitchen drain is clogged and it's a double sink, seal the drain on one side with a stopper before plunging the blocked drain.

The classic cleaning combination of baking soda and vinegar may help unclog a drain too. The chemical reaction that happens when they mix may dissolve some of the material clogging the drain. Pour about 1 cup of baking soda down the drain followed by 1 cup of white vinegar and cover the drain with a stopper. Let it sit for about 15 minutes and run hot water. If you notice some improvement, it may be worth trying this again. If not, you may have a stubborn clog that requires further intervention.

Using liquid clog removers is safer than using hydrochloric acid, though they may also damage older pipes. Make sure you know what your pipes are made of and read package directions before pouring chemical cleaners down your drain. Using enzymatic drain cleaners is the safer choice if you're unsure about what kind of pipes you have or if your home uses a septic system. They contain bacteria that eats through clogs and are generally much more gentle on your system than caustic or acidic cleaners that essentially burn through blockages.

If nothing works to clear the clog, it's time to call a plumber, who can use an industrial auger to get water flowing freely again.