Furnace Blowing Cold Air? Try these Troubleshooting Tips

One of the best things about living in South Carolina is that you can get through much of the winter wearing just a light jacket or even shorts. What’s not so great is when a cold snap comes in after you haven’t been using your furnace for a while and you suddenly find that you’re without heat. A good knowledge of troubleshooting furnace problems can prepare you for these occasions so that you’re able to quickly restore your heat and comfort.

Check the Thermostat First

Were you running the air conditioner on an unseasonably warm day? Forgetting to switch the thermostat from cooling to heating mode is surprisingly a very common cause of furnace “trouble.” Also make sure you have the temperature set as desired for heating mode. If your furnace still isn’t turning on, temporarily turn the thermostat up to the highest temperature to see if it will turn on. This will let you know if the thermostat’s thermometer isn’t calibrated properly or if the problem is somewhere else.

Is the Filter Fresh?

If you can hear the furnace running, but little to no warm air is coming out of the vents, the filter is the most likely culprit. Your filters really do need to be cleaned or replaced every 30 to 90 days as your furnace manual directs. If you don’t do this, they fill up with dust and dirt so that air can no longer pass through. Even a slightly dirty filter can cause a big drop in efficiency, so get in the habit of changing your filter whether or not you’ve noticed any furnace problems.

Does the Furnace Have Power?

If your furnace won’t turn on at all, check its power source. It may have tripped the circuit breaker or blown a fuse. Some furnaces have a plug instead of a permanent electrical connection, so look for a cord that might have been accidentally unplugged. If the problem was the circuit breaker or a fuse and it starts to happen frequently, call in a pro. There may be a serious electrical problem either in your furnace or in your home’s wiring.

Is the Pilot Light On?

If the furnace is running but only cold air is coming out, there may be a problem with the ignition system. Older furnaces use a constantly burning pilot light to start each heating cycle. If the pilot light won’t stay lit after you relight it, turn the gas off, clean the pilot orifice, relight the pilot light, and ensure that your furnace is tightly closed to prevent drafts from blowing the pilot light out. For newer furnaces using an electronic system, try turning the power off and then back on again to reset the system.

Did your troubleshooting steps not work? Contact Melton Heating & Air Conditioning for expert furnace repair in the Charlotte, Rock Hill, and Fort Mill areas.