HVAC Systems FAQ

Have a question about Heating, Ventilation, and Air Conditioning (HVAC) systems? We’ve answered many of the most commonly asked questions below. Have a question not listed below? Contact us for more information or to set up an appointment.


What type of heating and air conditioning system is right for me?

The most common types of heating and air conditioning systems are gas, electric, and oil systems. The type of heating and air conditioning system that’s best for you depends on a variety of factors: cost, efficiency, availability, and so forth. Here’s a basic guide to the different types of systems available and the advantages and disadvantages of each.


Electric heating and air conditioning systems are the most energy efficient mode of heating and cooling available. Electric heaters, such as heat pumps, rely on the earth’s natural resources by utilizing the warmth of the ground or the air to heat the home.

Another advantage of electric heat is the absence of any combustible fuels inside the home, which prevents the possibility of carbon monoxide leaks or explosions, unpleasant odors, fuel leaks, or ventilation issues. The types of electric heating and air conditioning systems include:

  • Electric Heat Pumps
  • Electric Air Conditioners
  • Ductless Mini-Split Systems
  • Geothermal Heat Pumps / Ground Source Heat Pumps


While not as energy efficient as electric power, heating your home with natural gas is still a great option for “clean” energy, meaning unpleasant odors as well as soot and ash can be avoided. Gas heat is ideal for anyone seeking an affordable, safe, effective mode of energy, which is why they are the most popular heating systems in the U.S.

There are two types of gas used to create heat: natural gas and propane gas. Natural gas is more convenient, but propane gas is cleaner and more affordable. Keep in mind that natural gas is not readily available in all areas, so propane may be your only option for gas heating. The types of heating and air conditioning systems that use gas or propane include:

  • Gas-Fired Warm Air Furnaces
  • Gas-Fired Hot Water Boilers / Hot Water Heaters
  • Automatic Standby Generators


Oil has long been used to heat homes due to its ability to provide heat quickly and efficiently. Heating your home with oil is also quite safe, since oil will not explode and the fumes are not lethal.

Oil systems also offer another advantage over gas heating systems – since oil systems produce odors and visible warning signs when not working properly, you have time to evacuate the home and alert authorities during an emergency, and the chances of carbon monoxide poisoning are slim. The types of heating and air conditioning systems that use gas or propane include:

  • Oil-Fired Warm Air Furnaces
  • Oil-Fired Hot Water Boilers / Hot Water Heaters

If you’re experiencing problems with your HVAC system, call today to have one of our friendly, professional technicians evaluate your system. We install, repair, and maintenance all types of HVAC systems for commercial and residential spaces. We’ll provide a custom quote to fit your needs.


How often should I change my air filter?

We recommend changing your air filter at least once a month. Neglecting to change your air filter on a regular basis can lead to a buildup of allergens, pollen, and pollutants in the air, which can exacerbate the symptoms of allergies and can even cause respiratory illnesses.

Disposable air filters are the most common type of air filter available, but non-disposable air filters can also be used. It’s important to clean non-disposable air filters once a month as well. Keep in mind that there are many different sizes of air filters. Your system should indicate which size filter you’ll need. Some systems even include more than one air filter that needs to be replaced regularly.

Your air filter is most likely located in the return air duct or next to your furnace. This is typically located in a basement, crawl space, utility closet, garage, or attic. If you’re unable to find the location of your air filter system or are having trouble replacing your air filter, contact us for assistance.


What is emergency heat and when should I use it?

Many people have questions about what emergency heat is and when it should be used. Emergency heat is a secondary heating source that protects your home from cold weather when your primary heating source, such as a heating pump, is broken or damaged. Heat pumps are designed to work in cold environments and can withstand temperatures in excess of -30 degrees, so don’t be afraid to run your primary heat source during the coldest weather.

Emergency heat should only be utilized in cases of emergency, rather than in situations in which colder than average weather is present. For example, if it’s 20 degrees outside, which is below freezing and colder than your average winter, your heat pump can still function properly in this temperature range, but if your heat pump is damaged by debris, weather, etc., turning on your emergency heat may be necessary to heat your home until your heat pump can be repaired. Keep in mind that it’s much more expensive to run emergency heat, so if it’s not absolutely necessary to heat your home, you may be able to prevent running emergency heat.

It’s a good idea to keep an eye on your heat pump during the colder months, to ensure snow, ice, and other debris do not pile up and damage the pump or its components. Clean your heat pump regularly to reduce the chances of a situation in which emergency heat is required.

Have a question about your heat pump or emergency heat source? Contact us for more information at 901-754-1515 or schedule an appointment online.


How can I save money on energy bills?

If you’re looking to save some money on your energy bills, there are a few things you can do to minimize costs. In fact, it’s a good idea to utilize these tips year-round for maximum energy efficiency.

Unplug Unused Appliances

This might be the most obvious method of lowering your energy bill, but it’s often the most neglected. Keeping unused kitchen appliances, charger cords, and other cables plugged in drains your energy sources. Staying in the habit of unplugging unused gadgets and accessories can save you a significant amount of money on your energy bill over the course of a year.

Turn Off the Lights

Another obvious yet often overlooked tip – turn off unused lights. Leaving the lights on in empty rooms and houses will add wasted energy costs to your bill every single month. If a room needs to lighted, consider using a small lamp to light the space rather than an overhead light, which uses more energy to run.

Utilize Ceiling Fans

Ceiling fans keep air circulating throughout your home, which can significantly lower energy costs in the warmer months when your air conditioner is working overtime to cool your home.

Switch Bulbs

One of the most affordable ways to get smart about using clean energy is to replace your standard light bulbs with energy efficient LEDs or CFLs (compact fluorescents). Keep in mind that CFLs can be harmful to people with epilepsy or those who are prone to seizures, so this is not a great option for commercial spaces.

Get Smart

Installing smart home gadgets like the Nest programmable thermostat can save you hundreds of dollars per year. These smart home accessories “learn” your patterns and preferences and utilize technology to provide a comfortable, energy efficient atmosphere throughout your home.

Mister Greenway Nashville installs and repairs smart home technology, including the Nest Cam and Nest thermostats. Learn more about smart home technology and how it can save you hundreds of dollars per year in energy costs.