With most thermostats, you have the option to continuously run your furnace fan or to have it run only when your furnace is running. There are a couple of good reasons why you might want to have your fan constantly running but those benefits come at a cost, so you need to weigh the pros and cons before making a decision. To find out if you should be running your furnace fan continuously, check out these tips from your friends at Allied Services, Inc.

Pros and Cons to Continuously Running a Furnace Fan


Setting your furnace fan to the “on” position is actually great for allergy sufferers. Because the air in your home will be constantly filtered through your HVAC unit, the air quality will improve. Additionally, if your system is energy-efficient, running your fan constantly could lower your electricity bill by balancing out the temperature in your house and reducing the need to turn up your thermostat. Finally, newer systems are actually designed to run continuously, as starting and stopping is often what is hardest on equipment. So, setting the fan to “on” will help extend the life of your unit.


Most of the pros of running your fan continuously rely on your unit being energy-efficient. So if it is an older model, running your fan won’t have as many benefits. Running your fan constantly will still improve your air quality, but your electric bill will likely rise. Also, you will need to change your air filter more often, so you’ll be spending more money on filters.

Ask an Expert

Deciding whether or not to leave on your fan depends on your lifestyle as well as the type of furnace you have installed in your home. If you work from home and suffer from allergies, it may make sense to leave your fan on to improve your air quality. However, if you work outside the home, don’t have allergies, and/or have an older furnace unit, you should set your fan to auto. Luckily, your friends at Allied Services can help you take the guesswork out of it. We can help you identify the best setting for your home and needs.

Call Allied Services today to discuss your heating needs or to receive an estimate for furnace repairs or furnace replacement. We serve Dayton, Ohio, and the surrounding communities. Contact us today at (937) 269-5059 to schedule an inspection and receive a free quote.