Need age on Rheem furnace

I would appreciate any help. Trying to determine the age on this Rheem forced air unit. Model RGDA-100C-ER

Ser# CN3D104 F4683 9228

Thanks in advance

Hi to all

Prestons list this model from 1989 to 1992 from the serial i would say it is a 1992 unit



Thanks Gerry!

Interesting Gerry, according to my cheat sheet Rheem serial numbers have an “F” in the middle followed by the week & year of manufacture. In this case I’d say 46th week of 1983.

Where the hell did you get a cheat sheet like that?

Thanks Michael. I’d be interested in one of those cheat sheets too!

I agree with Michael, 1983.

It’s the one that get’s posted here about once a week or so :slight_smile:

Jeffrey and Richard, this may be helpful:


Prestons Guide sucks I mean really sucks



Hey thanks for those cheat sheets I come across that **** a lot it seems like.

Definitely 1983
CN3D104 F4683 9228
The last two numbers of the second set is your year code.

Thanks to everyone. It’s nice to know that I can get answers from NACHI brothers/sisters!

Prestons has some good stuff in it, but I think the good stuff only accounts for about 50% of what’s in there. One also needs the Technical Reference Guide, which I’ve found to be far more accurate than Prestons.

And the others have it right; it is the 46th week of 1983.