. While it can temporarily melt grease, the drawbacks often outweigh this limited benefit. The Verdict Minor grease or soap scum clogs in metal pipes Worst for:
Plug the drain and let the fizzing reaction sit for 15 minutes. Flush with (not boiling). Use a Plunger or Drain Snake boiling water down drain
Pour half a cup of baking soda followed by half a cup of white vinegar down the drain. Plug the drain and let it fizz for 15 minutes, then flush with hot tap water (not boiling). Flush with (not boiling)
Most modern homes use PVC (polyvinyl chloride) for drain lines. PVC is rated to handle temperatures up to 140°F (60°C). Boiling water is 212°F (100°C). Pouring boiling water directly into a PVC drain can soften the plastic, warp the pipe, or melt the seals and glue at the joints. This leads to slow leaks behind walls or under sinks that may go unnoticed until mold develops. 2. Porcelain Sinks and Toilets Most modern homes use PVC (polyvinyl chloride) for
Pros reveal why you shouldn't pour boiling water down drains
Starchy pasta or potato water is a surprisingly effective, gentle drain cleaner. The starch creates a slightly viscous solution that can coat and carry away small debris. When boiling, it’s hot enough to melt grease while the starch acts as a mild abrasive. For this reason, many old-school plumbers will admit they pour boiling pasta water down their own drains once a week as a preventive measure.
If you are on septic, pour more than a quart of boiling water down the drain without mixing in cold water. Even better, let the water cool to room temperature before disposing of it.