Replaced failed 10-yr-old water heater with new Rheem ProTerra 50-gal hybrid unit. Old unit had significant tank corrosion. Updated plumbing connections with flex lines and installed expansion tank per code. Added drain pan with proper drainage. Configured unit for energy efficiency mode. Explained maintenance schedule and app controls to homeowner. Should see 60-70% energy savings compared to conventional electric. Left area spotless! Customer thrilled with same-day service after being without hot water since yesterday.