Failure Analysis of a Soldered Copper Tee in a Hot Water Heater Line

*** NOTE *** The majority of this work will be completed during the summer of 2026. Multiple studnets are working on this, but none have committed to attend IMAT yet. I'm confident one will attend and present this work so at this point I'm submitting this as a placeholder abstract, but I'm confident we'll present it at IMAT this year. - Elvin Beach

This failure analysis presentation will examine a leaking copper tee used as part of a residential hot water system. The hot water system has an unusual configuration with two forty gallon natural gas hot water heaters piped in series with the first water tank used to preheat the water and the second used to heat the water to the desired temperature for bathing. The owner has piped the hot water heaters in a manner that either could be bypassed in the event of it breakdown and replace while the other continued to provide hot water. The tee that failed was the critical part of this system used to bypass one of the water heaters and it developed a leak on the incoming (cooler water) side of the tee. This required replacement of a significant portion of the piping in the system. The tee was installed twelve years prior to the leak developing and the owner of the residence would like to know what lead to this location failing in the hot water system. This work will present a detailed failure analysis that includes collection of residue in and on the pipes and hot water heater components, a review of the water chemistry data from the City of Columbus, scanning electron microscope and energy dispersive x-ray spectroscopy analysis of the fracture and residue, and metallographic cross-sectional analysis of the leak location.