Originally Posted by garycoleman
After the call for heat, The ignitor glows, burners ignite. After 1-5 minutes of running (without reaching the desired thermostat temperature) the burner shutoff, the blower keeps running, and cold air comes out of the ducts. Could this be a bad ignitor? Or something else? Thanks
Shut off the power to furnace, remove the flame sensor and use steel wool to clean the sensor. Power the furnace, call for heat...this should do it.