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At a time when it seems like we have new jargon and acronyms flying at us all the time, it’s easy to get bogged down in “information overload.” One term you may have heard in the past is “HVAC” — perhaps you heard it used by a landlord or a technician to describe your air conditioner, but is that all this term means? In reality, it’s a bit more complex than just the way you get cold air. Good HVAC is a fundamental element of modern building design and an essential contributor to how you stay comfortable at home. So what is HVAC? Let’s break it down piece by piece to make it easy to understand.


Breaking Down the Main Elements of HVAC Systems


HVAC is an acronym that breaks down into three component parts: heating, ventilation, and air conditioning. Right away, we can see that HVAC isn’t a complex concept: it’s a simple catch-all term for the systems we use to control the climate of interior spaces, whether that means temperature, humidity, or even air quality. No matter whether it’s the dead of summer and swelteringly hot outside or if snow flurries fill the air, HVAC systems work hard to keep us comfortable.


With a basic answer to the question of  “what is HVAC?” established, let’s look at each component of the acronym in greater depth, then explore the constituent parts that make it all happen. 




Most homes, except those in specific climate zones, will need some way to heat interior spaces during the autumn and winter months. Even some areas that typically didn’t have high levels of heating demand in the past may need these solutions as extreme winter weather patterns evolve. Today, we’ve largely moved on from fireplaces and wood-burning stoves. Modern heating options typically use the same “forced air” system of blowers and ducts that air conditioners use. Heating can include:


  • Natural gas or propane furnaces and condensing furnaces
  • Electric resistance heating
  • Heating oil-fired furnaces
  • Radiant heating systems, such as boilers and radiators




Without keeping your windows and doors open all the time, there used to be no easy way to remove “stale” air from interior spaces and to replace it with fresh air. The “V” in “HVAC” stands for ventilation, and its goal is to solve this problem — to make it easier to exhaust air to the outdoors while also bringing in a fresh supply as needed. Ventilation systems can range from the very basic, as in most homes today, to the highly complex, such as those needed to provide adequate ventilation in large office buildings and high-rises. 


Air Conditioning


The “AC” of HVAC is familiar to nearly everyone. Air conditioners use special chemicals and physical processes to create a cooling effect on metal coils over which air blows. Air conditioning is essential not only for controlling the interior temperature of a space, but for also controlling its humidity. The air conditioning process naturally pulls moisture out of the air, making your home more comfortable.


How Do the Parts of an HVAC System Work?


With a clear sense of what each part of HVAC stands for, let’s take a quick look at how the individual components work in a broad sense. Check out more in-depth information to learn about the specific hardware elements of HVAC systems, such as ducts, blowers, and returns.


Furnaces function by burning fuel and exhausting the hot gases of combustion into a “heat exchanger,” a large series of twisting tubes. The hot gas transfers or “exchanges” its heat to the tubes. Air blowing over these tubes warms and flows into the home until the air temperature matches the thermostat temperature.


Air conditioners work on the principle of the refrigeration cycle. A chemical refrigerant undergoes compression and expansion, absorbing and releasing latent heat in the process. This process takes place partially outdoors and partially indoors. The key element is when the liquid refrigerant turns to gas in evaporator coils. Like in a furnace, air blows over these coils, cools, and then goes on to cool the home.


Ventilation can take the form of active exhaust fans or passive vents that allow air to escape to the ambient environment outdoors.


What is HVAC? Our Connection To Comfort

Next time you reach for the thermostat to adjust the temperature and you hear the rush of air through your vents, think about the magic of HVAC and how it allows us to always enjoy comfort at home or work. When you don’t need to wonder “what is HVAC?” you can also more capably identify potential issues based on changes in operation. Knowing when to call a professional technician for servicing and assistance ensures you can more easily avoid major headaches and equipment failures in the future. Be sure you always know who to call for help, and always make an effort to connect with licensed, insured, and highly experienced service providers so this critical system gets the care it needs.

If you’re a homeowner, you’ve surely heard the term HVAC before. However, you may not be aware of what exactly HVAC entails.


HVAC stands for Heating, Ventilation, and Air Conditioning, which covers elements ranging from the air conditioner in your home to larger, more complex systems that are sufficient for industrial or apartment blocks. A sufficient HVAC system provides indoor comfort as well as thermal control. It should incorporate the principles of thermodynamics, heat transfer, and fluid mechanics.


HVAC describes the systems that move air between indoor and outdoor areas and either cool down or warm up the air so that you feel cozy and toasty in winter but fresh and cool in the summer. Apart from helping you achieve the ideal temperature inside a building, an HVAC system is responsible for cleaning and filtering the air indoors to keep the humidity levels as manageable as possible. The system ensures an even distribution of treated air through a series of ducts and vents that transport and direct the air.

An HVAC Is a Complex Multi-Component Machine

While the term HVAC deals with multiple aspects of your home, each of these aspects has unique components and principles that work together to keep you comfortable. To further understand what HVAC means, we can break down these HVAC aspects into their primary elements.


The heating component of an HVAC system is usually a gas or electric furnace or a heat pump. Furnaces generally occupy the most space and consume the most energy from your HVAC elements. Furnaces contain an ignitor and burners that heat the air before moving from the heat exchanger to your interior rooms via ducts. Generally, homeowners will install this kind of heating system in an area that is not heavily occupied.


Unlike furnaces, heat pumps draw warm air from the outside and bring it in through the evaporator coil. They use the same refrigeration cycle as an air conditioner, but instead of releasing the air outside as a cooling system would, they push air towards a room. Heat pumps can also cool down a room by reversing the flow of air. They can be up to four times more efficient in consuming energy than traditional heating systems.


Ventilation is an essential part of the HVAC system. In addition to moving air, it eliminates excess moisture and harmful particles from the air. Ventilation systems include ducts, filters, vents, and exhaust fans. Homeowners will want to keep enough ventilation in an area to exchange the air every four hours, depending on the size of the home. The age of a home may also influence how much ventilation the interior space requires.


The air conditioner is one of the main components that every North American homeowner desires. Its primary function is to cool and monitor the indoor temperature via a thermostat. These systems are also partially responsible for reducing the humidity inside a house. Split systems are a popular option in which part of the air conditioner lies outside the home and the other lies in the interior: you’ll find the condenser and compressor outside, while the evaporator and expansion valve are inside.


If you’re considering installing an HVAC system as a homeowner, one factor to think about is the cost. A new HVAC installation can set you back between $3,000 to $30,000. Multiple factors will dictate the cost, including the efficiency of the equipment, the size of your house, your ductwork, and your area.


Bear in mind that cheaper rarely means better. Often, you’ll encounter problems down the line if you decide to go extra-cheap on your HVAC system. Apply the same principle to selecting the ideal HVAC contractor for ongoing maintenance: a professional who seems too good to be true in cost may be less experienced.

Keep HVAC Maintenance in Mind

Whether you install a furnace, water heater, or air conditioner, you’ll have to maintain each piece of equipment. These systems each contain parts that require attention—for example, you’ll have to change out the filters in your system regularly to place less strain on your HVAC components so that they can deliver an efficient performance.


Heating and cooling account for a significant portion of your energy bill, which is why you’ll want to ensure that your house is airtight and insulated. When you’re looking for a system, keep an eye out for high-efficiency options. You can measure the energy efficiency of an air conditioner through its Seasonal Energy Efficiency Ratio, or SEER, and a gas furnace through Annual Fuel Utilization Efficiency, or AFUE. Professional HVAC companies recommend that you opt for an air conditioner with a SEER rating of at least 20 and a gas furnace with an AFUE rating of 95 percent.


Sticking to these basics will ensure that your HVAC system works for you while keeping your energy bills as low as possible and your comfort levels high. If you’re unsure how to handle shopping for new equipment or maintaining your existing HVAC system, you can engage an HVAC technician to explain your options to you in terms that you understand so that you can make more informed decisions.