I have a trane xl 80 furnace and it quit last night. Hot water tank is gas and working okay. I checked the breakers and all on. The switch next to the furnace is on, I shut it off and it turns of the thermastat. Waited about 5 minutes and turned it back on with the top cover off the furnace, did not see a interlock switch, turned on the switch and heard a hum that I usually hear before it fires up, a blower motor just below the vent turns on and then I hear a click but no flame. Should I be able to see the ignighter light up? Is it to the front or back of the burners? Where do I get one?

Thanks Robert

The hum, is it just a hum or is that little venter motor actually spinning. Click, sound like it is from the gas valve? Hot surface ignitor is on the right hand side of the burners, usually a visual inspection will determine if it is bad, a crack, hole or burn spot in it.