So you’ve turned on your furnace to keep cozy during these chilly winter days…but instead of warm air filling the room, you’re met with a blast of cold air! What do you do?! First, don’t freak out and start calling HVAC companies right away. Take a deep breath. Then, troubleshoot yourself FIRST by following these 6 steps.
STEP 1: Make sure your furnace has warmed up
Think of your furnace like your car. It has to warm up when you first crank it for it to get going. If you get a cold blast of air when first firing up your furnace, but after a few minutes it begins to warm up, that is nothing to stress over. It is perfectly normal for cool air to blow from the vents while your furnace warms up. Of course, if warm air doesn’t start flowing after a few minutes, follow these next steps.
STEP 2: Check your thermostat settings
If there is a constant flow of cold air blowing from your furnace, check to see if your thermostat is set to “ON” or “AUTO”. If it is set to “ON”, your furnace blower will continuously run even when your furnace isn’t heating the air. Switch your thermostat to “AUTO”, so the fan will only blow when your furnace is heating the air.
STEP 3: Check the air filter
Believe it or not, a dirty air filter can really do some damage! A dirty air filter prevents airflow into your furnace, causing it to continuously run and ultimately overheat. When your furnace becomes overheated it signals the safety control to turn off the burners—which means no heat. However, your fan will continue to run, resulting in cold air being blown throughout your home. The solution here is to replace the air filter to return normal airflow to your furnace.
STEP 4: Check the pilot light (for a gas furnace)
If your gas furnace is older and is blowing cold air, your pilot light may have gone out. If you are comfortable doing so you can relight your pilot light or call your local utility company or one of our technicians to make sure it is properly lit. If the light continues to go out, you may need a preventative maintenance. These are usually done in the Fall, so another tip is to check this routine appointment off your list early!
STEP 5: Reset your system (for an electric furnace)
Turn the switch on your furnace to “OFF” and wait 30 seconds before turning the system back on. If you have trouble locating the “ON/OFF” switch, you can always turn off power at the circuit breaker level.
STEP 6: Check your ductwork
Older ductwork could be damaged or leaking, allowing warm air to escape before it reaches the vents to heat your home.
If you have completed this checklist and are still having issues with your furnace blowing cold air, it may mean that something else is causing an issue with your system and needs to be assessed by a Pro-Tech HVAC Home technician.
Pro-Tech HVAC Home offers new installation, replacement, repairs and maintenance of heating and air conditioning systems in the Annapolis area. Our customers rely on us for honest and reliable service for air conditioners, heat pumps, gas furnaces, Mitsubishi systems, and more. We’re happy to answer questions, troubleshoot, and help you choose the best HVAC system for you and your family. We’re always happy to help answer your questions, so please give us a call or send us an email.