Need the age of a GE heat pump. Model #BWB936A100A0, Serial # 255660726. Also have an electric furnace, model #BWE936611030 serial # 336578703. The home was built in 1975.
Prestons show the heat pump as manufactured between 1977-1980, I can’t help you with the electric furnace.
I believe what you have there are two Trane of Canada units manufactured for General Electric in 1977, coded to the seventh digit in the serial number.