A system and method for testing plumbing systems for leaks by which the original plumbing system is cleaned and flushed using ambient temperature water followed by cleaning and flushing with pressurized recirculating elevated temperature water to filter debris and contaminants, shocking the plumbing system with elevated temperature and high pressure surges followed by a hydrostatic pressure test designed to expose the existence of any leaks in the plumbing system in the rough plumbing stage of construction prior to enclosing the plumbing system in a structure.