My furnace will not run. There is a slight humming which we thought was the transformer. After replacing that, it is still not working. Initially the furnace would turn on but would not kick the heat in and blow any air. Any ideas?

Checked your blower motor and fan? Had a similar problem, with the burner coming on just fine, but the blower wasn't coming on. It would hum for a few seconds, then quit. Turned out the squirrel cage was stuck, and since it wouldn't move, it overloaded the motor, which shut down to keep from overheating. We adjusted and greased the bearings, and it's run fine ever since.

Could you please post Brand and model? Thank you. Also do you have and do you know how to use a multimeter?