Long video that explains the operation of an conventional standing pilot gas furnace.
Every component is included as described as it is disassembled.
From lighting the standing pilot furnace to to completely removing the heat exchanger.
Las the wiring is separated and covered wire by wire.
These old furnaces are very much out of date and it’s recommended to simply replace it.

00:00 AFUE
2:00 door safety switch/ door interlock
2:30 filter
3:00 cut away and first view of the heat exchanger
5:30 draft hood collection box
5:50 first view of combination gas valve
7:08 lighting pilot
11:10 firing the furnace
11:34 flame burning onnthe heat exchanger
21:00 pulling the blower assembly
24:00 removing the blower from the housing
31:20 blower wheel
33:0 blower bracket
44:50 top section of the furnace
35:00 combination gas valve, removing burners
38:00 lighting the pilot, clear view
41:15 igniting the burners out of the heat exchanger
43:12 pilot assembly
46:20 combination gas valve manifold spud orfice
49:38 burners
52:00 fusible link
53:00 Fan, Limit switch

56:00 wiring and wire diagram

1:10 pulling the heat exchanger