PVC Connection Failure at Pump: Stuck Zone or Bad Joint?

Melting PVC Indicates Dead-Head Pumping, Not Stuck Zone

A stuck-open zone would not overheat the pump—thermal breaker trips first. More likely a zone failed to open (dead head), causing pump to run against closed discharge, melting the PVC. The plumber’s metal nipple was correct, but the threaded PVC-to-galvanized joint failed due to heat. Check controller for unused zones with run time. A pressure tank/switch prevents this but adds cost.