[jyl]

Want to get advice on water heater.

I have a 50 gal, AO Smith, power vent water heater, about 20 years old. Has worked fine. The vent fan went out a few years ago, I bought a replacement and installed. A week ago the hot water went out, I tried the re-lighting process (turn fan off, turn gas valve off, wait, turn back on) but didn't work. 24 hours later I tried again and it worked. The water heater has been working fine since. Nevertheless, wife was so traumatized by 24 hours without hot water that she called a water heater service to come look. They advised the thermocouple is bad and the burner is corroded, said they won't repair such an old water heater because it is end of life and I'd spend $400-500 but the heater could start leaking the next day, and are giving me a bid to replace with a 50 gal Bradford White for $2200 or a tankless for $3000.

A quick glance online shows AO Smith burner assemblies for $100. I haven't checked for my exact model.

Is this something I can do myself? Should I?

Why do water heaters only last 15-20 years? Is that even true?