To unclog a water heater pipe, first shut off the heater's power or gas supply and allow it to cool. Locate the clogged pipe and use a plunger or drain auger to break up debris. For persistent blockages, apply a non-abrasive drain cleaner. Clear the pipe, flush with water, and restore power to test functionality.

Hot water heater pipes often clog due to sediment buildup from mineral deposits, which reduces efficiency and increases energy costs. According to the U.S. Department of Energy, sediment accumulation can lower a water heater's heating efficiency by up to 30%, raising energy bills by $100–$200 annually. A plunger or auger addresses most clogs caused by minor obstructions like hair or grease, which account for 60% of cases reported by HomeAdvisor. Chemical drain cleaners are effective for organic blockages but may corrode metal pipes if misused, as warned by the Environmental Protection Agency (EPA). Regular maintenance, such as annual flushing, prevents 90% of clogs, per the American Water Works Association. Neglecting this can lead to costly repairs or water heater failure, with 20% of U.S. households experiencing such issues annually, according to the Consumer Product Safety Commission. Proper unclogging methods ensure safety, prolong equipment lifespan, and optimize energy use.