I acquired (was given) an old Lennox furnace ID# G9D-55-M-1. The transformer was missing, I bought a new one a 115/24V model. I question the wiring configuration for the fan/gas valve and limit switches...
I am very capable of wiring the furnace controls just don’t have the knowledge to ensure that the wiring is correct. How do I wire this furnace to make it operate as it should via a thermostat?
Thanks
Ken

An old Lennox, even when it was new,, it wasn`t much to brag about. But,my thoughts aside.. there should be on the inside of access door a wiring diagram that could led you where you need to go,, if not Google lennex, and have the model number with you,, good luck

Unfortunately that door is missing... and the diagram.
I didn't mention it is for my garage have googled Lennox just have not seen a diagram yet. I was hoping someone could tell me "generically" how to do this. I would think its straight forward.
Thanks

The only GD9 unit listed is for a York/Coleman brand. There are many different items included on some furnaces and not on others so the factory wiring diagram is a must. Also if you are going to put that into your garage you have to elevate the furnace off the floor a minimum of 18 inches and install protection posts so your car cannot hit the unit. FYI. This is required by code as well as the manufactures instructions. Also the blower access door muct be replaced and the return air take from outside the room. This is also in the code since it is a fossil fuel furnace(gas burner) I believe.