HVAC 101: Understanding the Basics

From Parts to Processes, Here’s a Beginner’s Guide to HVAC

Air conditioners, heat pumps, furnaces—you know your home needs a working HVAC system, but unless you’re a trained contractor, you might not know exactly what you need. In fact, maybe you don’t even know where to start.  

From parts to processes, we’ve broken down the basics of HVAC and answered common questions so that you can feel confident when choosing and installing a new system. Let’s explore.

What Does HVAC Stand For?

HVAC stands for heating, ventilation and air conditioning. From keeping your home cool in the summer and warm in the winter to every temperature in between, HVAC systems help homes stay comfortable throughout the year and during any weather conditions. Your HVAC system also works to improve indoor air quality, ensuring that the air you breathe is filtered, clean and circulated around your home.

Common HVAC Terms and Parts to Know

Air conditioner: Cools the temperature in an indoor space by removing heat and moisture in the air. Air conditioners transfer unwanted heat and humidity outside and return the cooled air inside.

Furnace: Heats indoor air using natural gas, oil, or electricity, which is then circulated throughout a space. 

Air handler: Controls how air moves indoors. Air handlers are responsible for circulating air as part of the larger HVAC system.

Thermostat: Detects and controls temperature changes in a space to maintain optimal comfort. For example, when the temperature drops, the thermostat will send a signal to the furnace to produce heat. Thermostats range in functionality, from basic temperature control to smart options such as EcoNet® that allow homeowners to monitor home comfort from anywhere via a smartphone app.

Heat pump: Cools and heats an indoor space. Like an air conditioner, heat pumps remove unwanted heat and humidity and deliver cool air indoors. But only heat pumps can also provide heat during the colder months. That’s because heat pumps can run in reverse and draw heat from outside air to bring inside, even if temperatures are lower outside. They also run on electricity and are gaining in popularity as homes move toward electrification.

Refrigerant: Acts as the conveyor in your HVAC system to move heat energy in or out of the home, heating or cooling air in the process.

Ductwork: Routes air throughout a space. Made up of a system of metal or synthetic tubing called ducts, ductwork transports cooled or heated air indoor to provide thermal comfort. It is crucial that a home’s ductwork is property sized and installed to get the best performance and airflow from your HVAC system.

Types of HVAC Systems

There are three main types of HVAC systems: heating and cooling split systems, ductless systems and packaged heating and cooling systems.

Heating and cooling split systems are the most common type of HVAC systems and do as the name implies: They heat and cool homes. Typically, split systems include one indoor unit, such as a furnace or air handler, and one outdoor unit, such as an air conditioner or heat pump. In split systems, homeowners regulate temperature and comfort through their home’s thermostat, and air is distributed through its ductwork.

There is a unique type of split system, known has a hybrid or dual-fuel system, which includes a heat pump outside matched with a gas furnace inside. This system still uses a thermostat to control temperature and system operation, and it moves air through a home’s ductwork. The key difference is that a hybrid split system allows you to switch between gas and electric power for heating the home. As such, it can be a more efficient, sustainable option compared to a traditional split system.

In a ductless system, also known as a mini-split system, typically a wall or floor mounted air handler unit is connected to a heat pump installed outside. Conditioned air is distributed into the home directly from the indoor units without the use of ductwork. Because ductless units operate, as the name suggests, without the ductwork in your home, they provide heating and cooling limited to the areas of the home where they are installed. Single-zone ductless systems may be most beneficial in instances where you only want to heat one room, such as a new addition to your home that is not connected to its ductwork. Meanwhile multi-zone ductless systems can provide heating and cooling to multiple rooms. In either case, a ductless system can save the extra, often costly expense of resizing ductwork or updating the existing HVAC system.

Lastly, a packaged heating and cooling unit contains all necessary heating and cooling systems, such as a heat pump and air handler or an air conditioner and furnace, combined in one box. These packaged units are usually placed on the roof or alongside a home’s foundation. They are suitable for homes where interior space constraints don’t allow for an air handler or furnace, or the home is already ducted for a packaged system.

How Climate Impacts Your HVAC Solution

So, which type of HVAC system is best for you? That comes down to the structure of your home itself—and where you live. Because HVAC works to provide thermal comfort, your location’s climate is a big factor in the type of system that will best cool and heat your home.

For instance, let’s say you live in an area that stays consistently warm throughout the year, never dipping below freezing. Your home will likely need to be cooled more often than it needs to be heated. In this case, you might consider a cooling system that has a heat pump outside and an air handler inside.

On the other hand, if you live in an area that experiences warm summers and frigid winters, your HVAC system will likely need to both cool and heat depending on the season. An HVAC contractor can help address your individual HVAC needs and tailor the solution to ensure peak performance and comfort.

The Importance of Yearly Maintenance

Because your home HVAC system manages two essential elements—air quality and thermal comfort—annual maintenance is a must to ensure that your system is working efficiently and safely. During these preventive appointments, a contractor will do a thorough cleaning and inspection to make sure that all of your system’s parts and connections are functioning properly.

Oftentimes, staying on top of routine maintenance allows contractors to catch issues, or soon-to-be issues, before they become a costly problem, which can help save money in the long run. Seasonal maintenance can also help prevent problems when you need air conditioning or heat the most—say, on a 102-degree day or the coldest night of the year.

What to Expect When Working with an HVAC Contractor

The truth is, there is no one-size-fits-all approach to HVAC because every home is different. Whether you’re looking to schedule an annual maintenance call or install a new unit, a trained HVAC technician can offer suggestions based on your home’s needs, the climate you live in, your home sustainability goals, and more.

To learn more about your home’s HVAC needs or install a new unit, find an independent Rheem Pro near you.