Seasonal tune-ups usually prevent heating system malfunctions like this one, but if you find yourself with a heater that’s blowing cold or lukewarm air, here are three things that could be causing it in your Collin county home:
1. Issues With the Furnace Gas Supply
Check to see if the gas valve is turned on and the pilot light is lit. If the pilot light doesn’t turn on, it may need a cleaning, or the gas valve could be coated with grunge or in need of repair. Watch the unit until it turns on and check to see whether the burners ignite and heat. If they don’t, they may be coated with gunk. A faulty or dirty flame sensor (or thermocouple) will prevent the pilot light from staying lit and keep the burners from igniting. With a newer unit, the electronic ignition system may need adjustment or have a broken part.
2. Issues With the Heater Air Filter
A clogged filter can interfere with the ignition and cause the unit to blow cold air. A clogged filter can also overheat the unit or cause the furnace burner to turn off while the blower continues to run. That will cause cold air to come out of the vents. A filter that’s too dense and restricts airflow will cause the same problem. If airflow is blocked, the system has to run longer than it should heat your home, and it will overheat. Never run the unit with a dirty filter; it can destroy the heat exchanger.
3. Issues With the Heating System Thermostat
If the thermostat’s fan is set to “on” instead of “auto,” the blower fan will run continuously, even when the system isn’t generating heat. The result is intermittent cold air.
All of these issues are addressed during heating tune-ups, so it pays to have your unit serviced every fall. To learn more about the value of preventive maintenance, visit Allstars Electric Heating & Air or call us for help with system troubleshooting.