mor-flo air heater age

I have a mor-flo air heater model mf870pm with a serial # of FC411360508031 that I need a date for , the ac unit a goodman has a serial # that tells me it is from 1991 and both units look about the same age but i can’t match the serial # from the air heater to 1991 any help would be appreciated

If you use the mor-flo serial number it looks like 1989 or 2009 just a guess .

FC indicates March of either 1989 or 2009.

Rotating year code cycle.

Helpful site is here