To replace a water heater valve core, first shut off the water supply and disconnect the gas or electric power. Drain approximately 2–3 gallons of water to lower the tank pressure. Use pliers to loosen and remove the inlet and outlet pipes from the valve. Extract the old valve core by twisting and pulling it out. Clean the threads and seat with a pipe wrench and a brush. Insert the new valve core, ensuring it threads snugly and is seated properly. Reconnect the pipes, refill the tank, and restore power. Test for leaks by running hot water and checking pressure.

This process is critical because a damaged valve core can lead to water leaks, energy waste, and potential safety hazards. According to the U.S. Department of Energy, faulty water heaters account for 15% of household water damage claims, with valve failures being a leading cause. A 2021 study by the Environmental Protection Agency (EPA) found that improper valve maintenance increases energy consumption by 20–30% due to pressure loss and inefficient water flow. Replacing the valve core restores proper water flow, reduces energy waste, and extends the heater’s lifespan by 5–10 years. The average cost of replacement is $50–$150, but this is significantly lower than the $2,000–$5,000 expense of water damage repairs or heater replacement. Regular valve maintenance aligns with the EPA’s WaterSense program guidelines, which emphasize preventing leaks and promoting energy efficiency in household appliances.