Broken Tub/Shower Valve Repair

What happens here

This video provides a step-by-step guide on how to replace a faulty Moen 1222 Posi-Temp shower cartridge to fix a continuously running hot water leak. The process involves shutting off the main water supply, disassembling the faucet handle and trim, removing the old cartridge, cleaning the valve body, lubricating and installing a new cartridge, reassembling the faucet components, and applying new caulk.