Lubricate and Install New Cartridge

What happens here

Take the new Moen 1222 Posi-Temp cartridge. Apply silicone grease (often included with the cartridge) to all the O-rings and any rubber parts on the cartridge. This lubrication helps it slide in smoothly and prevents premature wear. Ensure the 'HC' (Hot/Cold) markings on the cartridge are facing upwards for correct orientation. Slide the new cartridge into the valve body until it is fully seated.

Goal: Apply silicone grease to the O-rings of the new cartridge and then carefully insert it into the valve body, ensuring correct orientation.