I bought a North trail FKDS last year, I’m having a problem with my furnace not working, the fan will kick on but the gas never goes, not the sail switch or the limit switch. When I turn on the heater the fan will kick for a minute then a grey box in the AC makes a click and it shuts off will sometimes do it rapidly. Is there anyone who’s had a problem with that or is there a possibility that it’s just gone bad??