Shower Faucet Leak Due to Worn Cartridge or Stem

Confirm this cause by shutting off the water supply and removing the handle to access the cartridge or stem assembly. Inspect the rubber O-rings, seals, and the body of the cartridge for signs of degradation, such as cracking, flattening, or loss of elasticity. If the cartridge cannot maintain physical resistance or seal against the valve wall, it is the primary cause of the leak.

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