Amitrol date code

[Bill Smith]

Anyone know how to decypher the Amitrol expansion tank date code?

[Marc D. Shunk]

A fair guess might be 11/21/91 on second shift.

[Michael Larson]

Originally Posted by Marc D. Shunk

A fair guess might be 11/21/91 on second shift.

That my my guess as well.
I wonder why you would want the D.O.M. for an expansion tank.

[Marc D. Shunk]

Originally Posted by mlarson

I wonder why you would want the D.O.M. for an expansion tank.

I was kinda wondering the same thing. I'm sure they do have a rated life, but at the end of their life, the bladder normally fails rather than the tank itself. Bladder failure is normally quickly evidenced by the expansion valve puking off, which isn't really a hazard as much as it is a nuisance. I'm sure there's something profound to be had from the expansion tank date code.

[Bill Smith]

No real big deal regarding the date code. Just curious. It could come in handy at some point. Thanks for the replies.

[Russel Ray]

Originally Posted by Marc D. Shunk

A fair guess might be 11/21/91 on second shift.

Good guess.

However, it's plant #11, 21st week of 1991, series 2.

The series could be several things, but usually it was either (1) the second shift, or (2) another the second assembly line in the same plant.

[Bill Smith]

FYI - Just got this email from Amtrol:

The date code for the Well X Trol, Extrol and Therm X Trol -

X XX XXX XX
Shift Tank Size Day of Year Year

Date Code 11219102 was manufactured on the 191day (July 10) of 2002.

Interesting - I never saw a day of manufacture used before.

[Russel Ray]

So they've changed. I'll update my research. Thanks.

[jkogel]

Sometimes, approx year of plumbing installation or renovation is helpful.

John Kogel
www.allsafehome.ca