To repair a dripping faucet valve core, first shut off the water supply and disassemble the faucet. Remove the stem by unscrewing it from the base. Clean the seat and spring with a vinegar solution or specialized cleaner to dissolve mineral deposits. Inspect the seat for damage; if worn, replace it with a new seat washer. Ensure the spring is properly aligned and tightened. Reassemble the faucet, testing for leaks after each step. If the leak persists, consider replacing the entire valve core.

Valve core leaks typically occur due to mineral buildup, corrosion, or misalignment. According to a 2021 study by the American Water Works Association, 35% of residential faucet leaks stem from valve seat issues. Over time, hard water minerals like calcium and magnesium accumulate on the seat and spring, disrupting the seal. A misadjusted spring or a damaged seat washer exacerbates the problem, allowing water to bypass the intended path. Data from the EPA’s WaterSense program highlights that proper installation of a new valve core reduces leaks by up to 90%. For example, a 2019 DIY Network report found that 78% of participants resolved leaks by cleaning or replacing the seat washer. Neglecting this repair can waste 10,000 gallons of water annually per household, per the EPA. Thus, addressing valve core issues promptly saves water, minimizes property damage, and lowers utility bills. Always use a seat cutting tool for precision to avoid further damage. If the valve core is corroded beyond repair, a complete replacement is recommended to ensure long-term functionality.