I have a commercial customer that has this old beasty from 1988. He wants a quote to replace the heat exchanger, tubes, inducing fan etc.. It looks like crap, but it still chuggs along on A/C pretty well. Obviously if it's more $$ to fix than replace he'll go for a new unit.
I think it's 150 kBtu heat and 75k btu cool. 3 phase.
manf. date 1/88
It would be a wonderful thing to find the manual so I can price out the heating section.