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Why is My Heater Blowing Cool Air?

If your heater isn’t delivering warm air, you have a problem that you need addressed. Reliable heating is important during the winters in Stafford, Virginia. Check these common issues to see if you can diagnose your heater’s problem or if you need to call a professional for more help.

Clogged Air Filter

Check the filter in your furnace and make sure it’s clean. You should change this filter at least once every three months. If you haven’t changed the filter recently, a new one may solve your problem. A dirty filter restricts airflow and makes it more difficult for your furnace to function properly. As a result, it wastes energy, strains itself and drives up your heating costs.

Malfunctioning Thermostat

Your thermostat is responsible for communicating the desired temperature to your furnace. If the thermostat isn’t reading your home’s temperature properly or sending the right message to your heater, you’ll find cool air coming through your vents. Check the thermostat to make sure you’ve input the right settings and have it set to heat rather than cool or to just run the fan. If the settings are accurate, call a service technician to inspect your thermostat and furnace more closely.

Disconnected Gas Line

If you have a gas furnace, make sure it’s getting the fuel that it needs. If your gas has been disconnected for any reason, this will prevent the furnace from delivering warm air. Check with your utility company to make sure your gas is on.

Pilot Light is Out

If your furnace has a pilot light, check this flame any time you’re having trouble with your heating. To reset the pilot light, you will typically:

  • Turn the furnace knob to off.
  • Wait five minutes.
  • Turn the furnace knob to pilot and push down.
  • Hold a lighter or match to the pilot opening while pressing the knob until it lights.
  • Turn the furnace knob to on.

If you can’t diagnose the problem with your heater easily using these tips, call a professional service technician. Brennan’s Heating & Air Conditioning can help you address and repair any heating issue. Give us a call at 703-783-0145.

Image provided by Shutterstock

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