Gas Furnace Slow to Come On? It Might Be Your Cold-Air Return Ducts

If your gas furnace doesn't come on right away or at all, even after you adjust the thermostat, you may think that the appliance is too old and needs to be replaced. Sometimes furnaces experience problems if the cold-air return ducts in your home clog up with dust. The ducts allow cold air to leave the home and circulate back to your furnace. If the furnace doesn't receive cold air from the furnace, it might not know exactly when to cycle on and off. Here's how dirty return air ducts affect your furnace and what you can do to make your situation better. 

How Does Dirt and Damage Affect Your Return Air Ducts?

You may not always see it, but dust circulates the air in your home every day. It settles on appliances, furnishings, and even your skin. During the winter months, your furnace picks up dust as it circulates air through the house. Over time, the dust builds up and blocks your cold-air return ducts in your flooring or elsewhere in the house.

Cold-air return ducts remove cool air from your indoor environment and transport it to your gas furnace. Although an air filter absorbs most of the dust, some particles can escape the filter and pass into the blower compartment of your appliance. The blower compartment houses the hearts of your furnace: the motor, the fan, and the combustion chamber.

The blower motor, fan, and combustion chamber rely on a clean environment to receive, heat, and transfer air to the plenum, which redistributes the air back into the home through supply ducts. If the three parts above collect too much dust, they stop working properly. Your furnace won't know when the home becomes too cold or when the thermostat kicks on.

It's possible for you to improve your furnace's poor performance with the right tips. 

How Do You Fix the Problem?

To get started, turn off your furnace and locate the cold-air return ducts in your house. Most homes use floor and baseboard vents for their return ducts, so look in these locations first. Every room of your home may contain a vent as well. If you can't find the vents or signs of any return ducts in your home, stop and contact a furnace contractor for assistance. But if you do find the vents, you can clean them. 

If the grated surfaces of the vents are wide enough, you should be able to look inside them. You may even see visible signs of dust and other problems, such as balls of hair and pieces of paper. Don't be alarmed if you find tiny toys, bobby pins, and other items inside the ducts. If you see these things, uncover the vents and vacuum out the ducts. 

If possible, use a damp rag to wipe out the insides of the ducts. You want to make the ducts as clean as possible to improve your furnace's airflow. Return power to your furnace and monitor its performance. If the furnace works great, you solved the problem. If the furnace still takes too long to come on, call a local contractor such as Getzschman Heating, LLC for further assistance.