Need assistance with the age of this AO Smith Water Heater please. Building Science and my other sources aren’t showing this format (see photo of Data plate)… Thanks in advance… 
Probably 1983 based on this post
http://www.nachi.org/forum/f22/older-ao-smith-water-heater-serial-number-42814/#post552552
Thanks Mike. 
Yo, Wayne… care to counter Mikey’s info? :twisted:
Jeff, I actually think that may be a 2008 made in the 30th week.
If this was from a recent inspection I think you would be able to tell if the water heater was from '83.
The site I use is www.buildingcenter.org
There was also a recall on some '08 AO Smith water heaters but they were manufactured in Nov.- Dec.
That’s an old style label.
I see many A.O Smiths around here.
True, but that’s also a long time for a water heater to last.
I couldn’t find a definitive serial number that matched his on the site I used but what I did see looked close to it.
It happens.
A water softener will greatly extend the life of a water heater.
Here is one from last week’s inspection, it was dated 1990.
I’ve seen much older WH still in use but usually in cottages.
I’m agreeing with Micheal on this, That is what I would say.
http://www.abouthomes.info/files/0090%205757.pdf
From this I would say 1977.
Perhaps this will help?
Like Mike mentioned, I see A.O. Smith products very often. I also see WH’s of this age all the time. The coloring and Data plate styling narrows it down to late 70’s/early 80’s… not much help in this case. My first gut reaction was 70’s, but am leaning to the 80’s.
That’s amazing. I can’t get one to last more than 4 years. And that’s with a water softener. Everything I’ve read, except for Mike, says that a softener hastens the corrosion. http://waterheatertimer.org/Replace-anode-rod.html
I went to the AO Smith site and they don’t even show that series (830) anymore.
They do have a parts book for the 900 series, printed in 1983.
So, late 70’s early 80’s as you stated.
I was curious so I shot an email to AO Smith. Here is the reply…
Good Afternoon Mike,
Based on the serial number the water heater was manufactured January 1977. Please let us know if we can assist you further.
Thank You,
Technical Support
That was my second guess, I believe in the OP’s picture there was a 77 in the data plate.
I Can’t speak for the water in your area but Calcium is the issue in this region.
I used to work for a water softener company.
Calcium builds up in the heater with a hard crust.
A water softener replaces the calcium with Sodium which is soft and does make a rock hard buildup.
I do not know what you are reading but please pass it along as what you “read” is the opposite of this:"
We have hard water in this area and generally water heaters around here last approximately 10 years. 37 years is unfathomable.
Nice job, Michael 