Fall has arrived in Central Ohio, meaning the time to turn on your home’s heat is quickly approaching. After a season out of use, it’s a good time to test your furnace for problems, to ensure your home is cozy and warm all winter long. Dealing with a broken or malfunctioning furnace is the last thing you want when the winter chill sets in.

If your furnace is blowing cold air instead of heat, there could be several reasons for the issue. While many are simple to resolve, you may need a professional to help with more complicated problems. In this post, we will review a number of issues that could be causing your furnace to blow cold air and how you can resolve them.

Your thermostat is having issues

It’s possible that your furnace is blowing cold air due to something as simple as the wrong thermostat setting. If your thermostat is set to ON instead of AUTO, the fan will be running continuously without any heat. Make sure your thermostat is switched to AUTO before attempting any fixes.

On the other hand, you could be dealing with a broken thermostat. This could cause cold air to blow because your furnace is receiving incorrect information from your settings. Luckily, a thermostat replacement is a relatively painless, low-cost solution. A new programmable or smart thermostat can even help save you more money in the long term by reducing your energy costs.

The control board is broken

Your furnace’s electronic control panel could also be the culprit of cold air if it’s not working correctly. Try to reset your system by turning off your furnace’s power, waiting for a few minutes, and then turning the system back on. If you’re still having issues, reach out to an HVAC professional.

The pilot light or electronic ignition is out

If you have an older furnace, your pilot light could be out due to a draft or dirty valve. Relighting the pilot light is a fairly easy process, but if you have trouble getting it lit, it could be due to a faulty valve or thermocouple. Or, if your furnace is a newer model with an electronic ignition, it could need an adjustment or replacement. An HVAC professional can diagnose problems with your pilot light or ignition and assist with a solution.

Your gas furnace needs fuel

If your furnace uses gas to heat your home, it needs a consistent supply of fuel to generate heat. It may simply be out of or low on gas. But even when it runs out of fuel, your furnace will continue to circulate cold air. Ensure that your gas valve is turned on and other gas appliances in your home are working correctly. If that’s the case, you may need to call a professional.

Your air filter needs to be changed

A dirty air filter could be the cause of your furnace blowing cold air. When your filter is dirty, airflow is blocked, preventing warm air from properly heating your home. Ideally, your air filter should be changed about once every three months, but that can vary depending on your household.  We recommend checking your filter once every 30 days to monitor for dust and blockages.

Alternatively, blocked condensate lines could be causing the problem. Standing water around your furnace is a typical sign of a line blockage. If you notice water pooling around your unit, reach out to a professional for assistance.

Your furnace is overheated

When your furnace overheats, it can activate a safety mode that turns off the ignition. This can cause cold air to be blown throughout your home. If your furnace is regularly overheating, it could initiate the safety mode on the main limit, which is a safety feature inside the unit. A faulty main limit could also be the cause of cold air.

Your ducts are leaking air

Damaged ducts with holes or cracks could cause air leakages, resulting in cold air entering your home or heat escaping. This could be attributed to normal wear and tear, or it could be an issue with the way the ductwork was originally installed. If you think your ducts are leaking, enlist a professional to help determine the cause and find a resolution.

Get help from a professional

Still can’t find a solution? Call an HVAC professional for help. Our trained experts in Central Ohio can help you identify and fix the issue quickly and painlessly. We also offer furnace repairs and seasonal HVAC maintenance to keep your equipment in good condition year-round. Contact us at Expert HVAC Services using this quick form today!

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