What is this unit, a York or Luxaire?
How old do ya figger the sucker is? Doesn't look an recent vintage York/Luxaire model #s.
armstrong... b- i think signals 208-3-230 grtc is an armstrong #. maybe ... not sure. possibly a 150 grtc60b?
i belong to peta ... people eating tasty animals. all my opinions are just mine.
looks like a 5-ton armstrong, i think the 15 is actually 150, indicating the heating capacity in btu's