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When you tried to light with a lighter, did the burners light?
You may have a open limit switch.
The Main limit switch is a rectangular or square looking device that has two wires attached to it and is usually located inside the furnace cabinet on the back panel wall.
Locate it and let me know when you find it.
black rectanglular shaped plate made by texas instruments?
Yes that is it! Just to verify, is there a number such as this on it? L240 - 40F?
just a sec
That is it.
Remove the two wires and use a piece of wire to jumper them together.
While they are jumpered together, attempt to turn the heat on.
then it will work?
We don't know yet. This is a troubleshooting test.
Let me know what happens.
gave it a shot, jumped the wires together... nothing different happened
Place the wires back
Use a volt meter to see if the gas valve is receiving 24 volts when the igniter is glowing.