Why is My Furnace Blowing Cold Air? - Ernst Heating & Cooling

Why is My Furnace Blowing Cold Air?

furnace blowing cold air

There’s nothing quite as cozy as hunkering down in your warm home during a winter storm. The weather outside might be frightful, but you’re inside enjoying your comfortable heat thanks to your working furnace. It’s all good until you notice things aren’t as warm as they should be, and your furnace is blowing cool air instead of offering a warm respite. Why is this happening? Ernst Heating & Cooling of Hamel, IL, is here to help you determine whether this is a quick fix or a job for our HVAC experts.

Read on for reasons why the furnace may be full of cold air and how you can bring back the heat.

Your thermostat is set incorrectly.

Do you have thermostat wars at home? During your last big gathering, did a guest opt to turn off the heat and open a few windows for their comfort? Sometimes your furnace problem is simply a thermostat problem. Before panicking, ensure the thermostat is set to heat rather than in the “off” or “cool” setting. Did someone leave your thermostat fan set to “always on?” Switch it back to “auto,” and you’ll only feel the fan when the heat is running. Is the thermostat new? Some thermostats are not compatible with specific heating systems. Ernst Heating & Cooling experts can look at and make sure the thermostat and the furnace are working together efficiently.

Your furnace is overheating.

Your furnace has a built-in safety feature that switches off the heat when the unit becomes too warm. This same feature keeps the fan blowing to help cool down the unit so that you might notice cool air coming from your registers. What causes overheating? Dirt and dust can build up on the internal components, forcing the furnace to work too hard to produce your home’s heat. Broken or misfunctioning internal parts may also cause the heat to turn off. Enrolling in the Ernst Comfort Plan is one of the best ways to catch these minor problems before they shut off the heat. This annual maintenance plan includes two precision tune-ups yearly to ensure the working parts are in order before you need them to work hard during extreme weather conditions.

You may have ductwork problems.

Once your furnace heats the air, it pumps it through a system of connecting ducts leading to the various spaces throughout your home. If your home’s ducts have cracks or holes, they can let in cool air from the attic or other unheated areas. It can be challenging to locate and seal these problems. Let an expert like Ernst Heating & Cooling inspect your ductwork and make the necessary fixes.

Your pilot light is out.

Your older furnace may have a pilot light that is always on to ignite the larger burner. If a draft or dirty valve blows out the pilot light, your furnace will not be able to ignite and heat your home. Your furnace may have instructions for relighting the pilot light, or you may prefer to call in a professional HVAC expert.

You have a cracked heat exchanger.

Your furnace creates heat by combusting gas in a sealed chamber. A heat exchanger keeps these toxic gases from escaping and moving into your home. A cracked heat exchanger is a serious issue that can lead to carbon monoxide poisoning and should be addressed immediately.

If you’ve checked for the usual suspects and cannot find anything awry, it may be time to call in the Ernst Heating & Cooling experts. Our trained HVAC technicians can find and fix the source of your problem, often in just one visit. If the cold air is blowing – inside your home, not outside – call Ernst Heating & Cooling now at 618.217.1836 or schedule an appointment online. Stay warm this winter with Ernst Heating & Cooling.

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