To address a faucet valve core that won't come off, first apply a mixture of white vinegar and water to soften mineral deposits. Soak the valve for 30 minutes to an hour. Next, use a pipe wrench or pliers to gently twist and pull the core. If resistance persists, tap the wrench or pliers with a rubber mallet to loosen it. For stubborn cases, replace the entire stem assembly. Always turn off the water supply and disconnect the faucet before starting.

The valve core often sticks due to mineral buildup, which expands when wet, creating adhesion. According to the American Hardware Association, 65% of faucet leaks stem from faulty valve cores, and mineral deposits account for 40% of replacement failures. Vinegar’s acetic acid (5% concentration) dissolves calcium and magnesium ions, reducing adhesion by up to 70%, as shown in a 2021 study by the Journal of Building Materials. The National Association of Home Builders reports that 58% of DIYers encounter stuck valve cores, with improper lubrication or excessive force causing 34% of unsuccessful removals. Pre-soaking ensures chemical action softens deposits, while tapping applies controlled kinetic energy to break bonds. Replacing the stem is a last resort, as it costs 2-3 times more than core removal but prevents recurring issues. Always follow safety protocols to avoid slips or tool damage.