Warning: my water heater died on a Sunday night and I fixed it with a $23 part
Sunday around 9pm I walked into the garage here in Amarillo and found a puddle spreading under the water heater, and the pilot was already out. I pulled the access panel, saw the thermocouple was corroded, and ran to the hardware store on Georgia Street before they closed at 10. Swapped in a new one for $23 and had hot water back by 10:30 that night. My neighbor said I got lucky and should just replace the whole unit, but the tank is only 6 years old. Anyone else had a thermocouple go bad this early, or did I just get a bad one from the factory?
Lucky" is a stretch. You found the bad part and fixed it, that's called knowing what you're doing. Six years is early for a thermocouple but it happens, I wouldn't yank a good tank over it.