Water heater inlet corrosion after 4 years? Installer claims they did everything right

corrosiongalvanic-corrosionwater-heater

Similar to this question, I've got severe corrosion on my 4 year old water heater inlet. I was having the heater flushed when this was discovered, and the person flushing it said it was caused by the installer not using a dialectric nipple.

Picture of corrosion

So I contacted the installer, who claims that the copper flex is dielectric so a dielectric nipple is not needed. Is this possibly true? If so, what else could have caused it?

It would be great to know if the original installer is being honest. If they are, I'll have them do the work to fix it. If not, I'll find a new plumber/plumbing company.

Best Answer

My educated guess without being there is that the flex connector joint was not installed correctly or is just leaking. I never liked this type of installation since it was made for the novice and not a professional. I always used hard copper and a non-lead solder containing silver. I also never used galvanized piping, just brass fittings and copper tubing. Whoever installed this did a sloppy, non-professional job.