What Are HVAC Systems And How Do They Work?

Becoming a homeowner comes with a serious learning curve. Not only do you have to navigate the home buying process, but there’s also plenty you’ll need to know about your home itself.

One of the most important components of your home is the HVAC system – short for heating, ventilation and air conditioning. In this article, you’ll learn everything you need to know about HVAC systems, including how they work, the different types, the cost of a new one and more.

What Is An HVAC System?

An HVAC system is a system in your home that’s designed to regulate the temperature in your home and provide air quality by keeping the air moving between the inside of your home and the outside. An HVAC system has three primary functions: heating, cooling and ventilation. Not only does this system keep you comfortable in your home, but it also keeps your family healthy and protects your home’s interior from damage.

In some cases, your HVAC system may actually be three separate systems. But often, they are combined systems using the same internal ducts in your home (or the same ductless system).

Heating

The first important function of an HVAC system is to heat your home, keeping it warm during the colder seasons. When you set your desired temperature on the thermostat, your HVAC system responds by keeping your home’s internal temperature at that setting. Once the temperature falls below that setting, the thermostat sends a signal to your HVAC system to create more heat.

The main component of the heating system in your HVAC system is either the furnace or the heat pump. Both create the heat that’s dispersed through your home, but in different ways. A furnace runs off propane or oil only to heat your home, while a heat pump runs off electricity to both heat and cool your home.

If you live in a colder climate with more substantial heating needs, your home is most likely to have a furnace. You are likely to have a heat pump only if you live in a moderate climate.

Ventilation

The ventilation component of your HVAC system is what delivers the heated or cooled air to the various rooms in your home. Not only does the ventilation component distribute the air throughout your home, but it also filters and purifies the air for the benefit of your home’s air quality, your family’s health, and the HVAC system itself.

Air Conditioning

The final function of an HVAC system is its cooling component, which has parts both inside and outside of the home as a way to regulate the temperature.

The air conditioning component of your home has a main unit, the condensing unit, which is typically found outside, either behind or on the side of the house. It also includes a condenser coil and an evaporator coil.

How Does An HVAC System Work?

As we’ve discussed, an HVAC system has a few primary functions. First, it controls the air temperature in your home through either heating or cooling.

When your HVAC system heats your home, it uses either your heat pump or your furnace to create warm air. A heat pump works by drawing in cold outside air, drawing heat into the refrigerant, and drawing air over heated coils to bring it to the desired temperature.

In the case of a furnace, the HVAC system draws in air through the ducts and into the furnace, where it heats it and pushes the heated air back out.

The HVAC is also responsible for cooling your home. First, the main unit has a condenser coil, which cools the refrigerant and sends the liquid to the evaporator coils inside the home. The evaporator coil does two things: It changes the liquid to a gas to be dispersed throughout the home via ductwork and absorbs heat from the inside of your home to send it back to the condenser unit to disperse outside.

The HVAC is also responsible for distributing hot or cold air throughout your home using ductwork. The ductwork acts as the various tunnels the air travels through, while the vents act as the doors, allowing air to enter the room or, if closed, blocking it from entering.

Vents can also direct airflow. If the vents are pointed down, they will direct the aid downward. If they’re pointed up, they’ll direct the air up. Vents can be opened, closed, and pointed either way manually by the homeowner. This can help you regulate temperature better. For example, if one room is normally very hot, you can close off the vent to keep the heat from going into that room.

Parts Of An HVAC System

Each part of your HVAC system plays an important role in helping it provide proper heating, cooling and ventilation for your home. Here are the important parts of your HVAC system that contribute to its overall performance and functionality.

• Air return: Your HVAC’s air return serves as the starting point of the ventilation cycle. It pulls in the warm air and moisture in your home and draws it through the air filter, which then helps it flow to the main HVAC system.
• Air ducts: The air ducts in your home help to circulate hot or cold air throughout the home to heat, cool and ventilate each room. Your air ducts are connected to your HVAC unit, which sends filtered air to the various ducts in your home.
• Compressor: The compressor is one of the most important parts of your home’s HVAC system. In your air conditioner, the compressor works to transfer heat from an enclosed space to the outside, pulling hot air with it and then returning cooled air to your home.
• Coils: Your HVAC system’s evaporator coil is found inside of the split-system air conditioner. The refrigerant flows through this coil and it absorbs heat from indoor air, causing condensation and lowering the humidity in your home. The system also has a condenser coil, which is where the refrigerant gas flows through before the cooling cycle restarts.
• Exhaust outlets: The exhaust outlets are the part of your HVAC system where the exhaust is expelled. The exhaust outlets are especially important during the winter months, when your HVAC is responsible for heating your home.
• Electrical components: Your HVAC system has several electrical components that help it function properly. Included in the electrical components are the compressor, motors and capacitors, each of which is connected together through the electrical wiring.
• Filters: This part of your HVAC system is a part of the air return where the air is drawn through. The filter removes impurities from the air both as a way of protecting your home’s HVAC system and improving your home’s air quality.
• Thermostats: The thermostat is the sensor that allows your HVAC system to function properly. First, the thermostat is programmable, meaning it allows homeowners to set their desired temperature. The thermostat then senses your home’s internal temperature and directs the heating and cooling components.

Types Of HVAC Systems

There are five types of HVAC systems you’re likely to find in a home: split systems, hybrid split systems, zone systems, ductless or mini-split systems, and packaged systems.

Split System 

The split system is the most popular type of HVAC system. It has both indoor and outdoor units that connect to one another. The outdoor component has the condensing unit and condenser coil, while the inside has the evaporator coil and furnace or heat pump. A thermostat controls the heating and cooling. Once the air is heated or cooled, it’s transported throughout the home through ductwork, then delivered through the vents.

Hybrid Split System

A hybrid split system features both a heat pump and a furnace. Since heat pumps are best used in mild climates, the furnace takes over the heating duties when the temperature drops below 40 degrees. This system also uses a thermostat and delivers the air via ductwork.

Zoned System

A zoned HVAC system is often used in larger homes as a way of controlling different parts of your home separately. In this type of system, there are different thermostats in different zones of your home. These are ideal for larger homes, since you can separately control different parts of the home. They’re also energy-efficient, since you may have reduced heating or cooling needs in parts of your home you don’t use as often.

In a zoned HVAC system, each of your thermostats is connected to a central control panel. There are dampers that regulate airflow inside a duct. They open and close to allow hot or cold air to pass through until the zone has reached the desired temperature.

Ductless Or Mini-Split System

As the name suggests, a ductless, mini-split system doesn’t use ductwork. Instead, separate mini-split units are used in specific zones or rooms of the home and attached to an outdoor heat pump or air conditioner. Because they don’t require ductwork, they are popular for home additions. They also offer greater control over the heating and cooling in different rooms of the home. This can lead to better energy efficiency since you can choose what rooms to heat or cool and when.

Packaged System

Packaged HVAC systems feature both heating and cooling systems all in one outdoor unit that’s installed on the roof of a home or near the foundation. This system delivers warm or cool air through the ductwork as well. This space-saving HVAC system is good for small homes with limited room.

How Long Do HVAC Systems Last?

The average lifespan of an HVAC system depends partially on the type of system you have. But generally speaking, you can expect yours to last for anywhere from 15 to 30 years.

With such a wide range, it can be difficult to know when it’s time to replace your HVAC system. There are a few things you can look out for that can be signs your HVAC system is ready to be replaced. Those signs include increased energy bills, reduced air quality, and frequent repairs.

The good news is there are things you can do to make your HVAC system last longer. Be sure to schedule your regular maintenance and deal with issues as soon as they arise. You can also extend your HVAC system’s lifespan by changing your air filter more frequently. Not only will it improve your home’s air quality, but it will help your HVAC system run easier.

Finally, there are a few things you can do around the house to alleviate the burden put on your furnace. Check for and seal drafts around the home, winterize your windows, and check your vents to make sure they’re allowing proper airflow.

How Much Is A New HVAC System?

Depending on the type of HVAC system you have, you can expect to pay between $5,000 and $10,000 for a new one. The amount you’ll pay depends on the type of system you have, the type or brand you’ll get to replace it, the size of your system, local labor costs, and whether you need to replace the full system or just certain components.

The good news is there are ways to fund your new HVAC system outside of just paying in cash. Those strategies include getting a home warranty or a cash-out refinance.

What Is The Best HVAC System For My Home?

When it comes to choosing the best HVAC system, there’s not necessarily one option that’s best. Instead, the best system for you depends on factors that include your home’s location and size, as well as your desire to save energy or money.

The first thing to consider when choosing an HVAC system is your area’s climate. As we’ve mentioned previously, certain types of systems are best suited for either moderate or cold climates. Another thing to consider is energy efficiency. The more energy-efficient your home, the more you’ll save on energy.

Another thing to consider when choosing an HVAC system is the capacity you need. Generally speaking, the larger your home, the greater capacity you’ll need.

Finally, consider your budget. Certain types of HVAC systems, while they may be better suited to your needs, are also more expensive. However, the increased price is usually worth it in the long run.

The Bottom Line

Your HVAC system is one of the most important systems in your home. Not only does it heat and cool your home, but it also ensures the best air quality for you and your family.

If the HVAC system that best fits your needs is on the pricier side, you might want to consider financing options. Cash-out refinances tend to be highly attractive options because they let you turn existing home equity into an opportunity to further increase your home’s value to you and others. If that sounds appealing, why not start the process to get a cash-out-refinance today?