Before you ever pour boiling water down a drain, find out what your drain pipes are made of.
For metal pipes only: Pour 1/2 cup of table salt down the drain, followed by a pot of nearly boiling water. The salt is abrasive and helps scrub the pipe walls as the water drains. This is excellent for eliminating odors caused by bacteria film, but it is not for clogs. boiling water down drain
Never pour boiling water into a garbage disposal. The heat can melt the rubber splash guards, warp the plastic internal components, and crack the grinding chamber. Instead, use cold water while running the disposal (to solidify any grease so it can be chopped), and then flush with hot tap water afterward. Before you ever pour boiling water down a
This is the closest safe alternative. Pour 1/2 cup of baking soda down the drain, followed by 1 cup of white vinegar. Cover the drain to force the reaction down. Wait 10 minutes. Chase it with hot tap water (not boiling—around 120°F to 130°F). The fuzzy, expanding foam dislodges organic matter without melting PVC. This is excellent for eliminating odors caused by
| Do | Don't | | :--- | :--- | | Do pour slowly to allow pipes to adjust to the heat. | Don't pour boiling water into a toilet bowl (it can crack the porcelain). | | Do use this method on bathroom sinks to dissolve soap scum and hair gel. | Don't use boiling water if you have a "bucket trap" under your sink (rare, but the heat can ruin the seal). | | Do use a sink strainer afterward to prevent future clogs. | Don't rely on boiling water for deep blockages; if the water doesn't go down, call a plumber. |
Ironically, while metal handles heat better than plastic, old metal pipes present a different problem.