M-Core Cartridge Basics

Preparation:

• The Water Supply shut off valves must be turned off, see article How to Turn Off Water Supply To The Faucet.
• The following instructions assume the handle and associated handle pieces have been removed. For additional details, visit Single Handle Shower: M-Core and select the type you are repairing. The faucet guide will contain specific information on handle assemblies associated with that style of product.
• We recommend covering the drain before beginning so not to lose any parts down the drain.

The M-Core valve system includes two configurations, shower and tub/shower. The cartridge alignment varies by configuration. Review the information below paying special attention to the light blue highlighted areas. These indicate the specific orientation of the cartridge parts based on which type of shower system you have.

A Shower only system would use a 3 Port Valve (Note orientation of light blue highlighted areas)

Adapter with Check Valves

Pressure Balancing Puck Assembly

Cartridge

 A Tub and Shower system would use a 4 Port Valve (Note orientation of light blue highlighted areas)

Adapter with Check Valves

Pressure Balancing Puck Assembly

Cartridge