I have an old York furnace. Serial number DM054518 tells me it was made in Apr 82, which is consistent with a major remodel of this old home. Can anyone tell me from the serial number what the model is? I pulled the plate and it's almost unreadable but what looks like the model number, CG140D16N-1 is not consistent with any others I've seen listed here. At the time I believe York was owned by Borg-Warner. Anyway, I'd like to get a manual for the furnace.