Shower Valve Not Working

Most shower valve problems are a stuck cartridge or a scaled-up pressure balancer, both replaceable in an hour with the right part.

Common causes

• Scaled cartridge from hard water
• Failed pressure-balancing spool
• Worn diverter to the shower head
• Debris lodged behind the cartridge

Step-by-step

1. 01Shut off the water at the main or in-line stops if present
2. 02Pop the handle and trim, remove the retaining clip, pull the cartridge
3. 03Match to the manufacturer (Moen, Delta, Grohe) at a plumbing supply
4. 04Grease the O-rings, reseat, and test at low then full flow

When to call Northbridge

• Cartridge is seized in the valve body
• Valve body is corroded or leaking behind the wall
• No in-line stops and shutting off the whole house is a problem
• Rebuild kit didn't fix pressure or temperature