7 common HVAC myths dispelled

Published by Parisa Ostovari

Throughout my years in the heating and cooling business, I’ve discovered there are a number of HVAC myths floating around. In this post I’ll be sharing some of the most common HVAC myths and dispelling them for you, so you know the best ways to care for and maintain your HVAC system.

Myth #1: The bigger the HVAC system size, the better
A lot of people might be surprised to learn that when it comes to HVAC system size – bigger is not better. When your HVAC system is too large, it costs more to run and it’s harder to control the indoor temperature and humidity levels.

To maximize efficiency, choose a smaller system that allows your AC to operate continuously. When your system is able to run continuously, the AC won’t shift between high-blast and not running at all. With an HVAC system that is the right size for your home, you’ll likely feel more comfortable during the summer in a house that’s set at 75 degrees with a lower humidity level than you would in a home that was set at 68 degrees with a higher humidity level.

Myth #2: Changing the thermostat settings will fix my temperature problems
Once you have the right size HVAC system, there’s still an ideal temperature range to consider. HVAC systems work by either being turned on or off. Setting the temperature on the thermostat really low or really high won’t get you to your desired indoor temperature faster. The only thing it does do is make your AC or furnace work longer.

During the summer, it’s best to not set your thermostat lower than 70 to 72 degrees. Most units are not designed to cool a house below that point, and you risk the system freezing up. In the winter, it can be tempting to walk over to your thermostat and crank up the heat. In the winter, I wouldn’t set your furnace much higher than 75 and definitely not above 78 degrees. This temperature setting can be too hot for a house and you’d be wasting a great deal of energy.

Myth #3: Routine HVAC maintenance isn’t important
You routinely change the oil and rotate the tires on your car to keep it running smoothly. So why ignore your HVAC system? Investing in regular maintenance can save you time and money. There are many parts to an HVAC system – electrical parts, coils and motors. Not taking care of your system can lead to expensive repairs that could have been avoided with regular maintenance and cleaning.

Maintenance is also an important step in extending the life of your heating and cooling system. A furnace or air conditioner can last up to 20 years — but not if it’s poorly maintained.

Myth #4: I should cover my AC in the winter
You may have read or heard from a neighbor that you need to cover your AC unit to protect it from snow. Covering the top and sides of your air conditioner can allow moisture to build up, causing damage to the unit. It also provides a nice warm place for mice or other rodents to build a nest and pass time by chewing away at the wires. If you do cover your AC in the winter, only cover the top. Manufacturer guidelines don’t recommend covering the sides of your air conditioner.

Myth #5: The location of my thermostat isn’t important
The thermostat is the brain of your HVAC system. It is what tells your furnace or AC to turn on and off. Where you place your thermostat can have an impact on how accurately it operates. For example, placing the thermostat in an area of your home where it could receive a lot of direct sunlight during the day could cause the thermostat to think it’s hotter in your house than it actually is. The room where you place the thermostat also matters. Hallways have a different airflow than the rest of the home and are not often occupied. And the heat that is generated by the stove and oven in your kitchen can create the same problem as direct sunlight and cause your thermostat to think your house is warmer than it actually is.

Myth #6: I don’t need to change my furnace filter
Changing your furnace filter is very important. In fact, changing the filter is the No. 1 thing a you can do to maintain your furnace. A dirty furnace filter will restrict air flow into the HVAC system and decrease its efficiency. It’s also important to remember that all of the air in your home passes through the furnace filter. A dirty filter can have a significant impact on the indoor air quality inside your home. This video shares the different types of filters and how often each one needs changing.

Myth #7: I shouldn’t run the AC fan continuously
This is a common misconception. We recommend that homeowners keep their AC fan set to “On.” Most thermostats are located on the main level of the home, helping the first floor and basement maintain a comfortable indoor temperature. Keeping the fan running constantly will help air flow more evenly throughout your home.

Running your AC system fan all day can actually use less energy and help keep your house more comfortable. It will also cause less wear on your motor because it’s not starting and stopping all day like it would when set to “Auto.”

Our trained and certified HVAC technicians are here to help. If you have any questions about your HVAC system, connect with us online or call 515-244-8911.