A basic overview of the primary components of a quality HVAC system

ABCs of HVACLike many aspects of modern life, our heating and cooling systems are run by technology that’s easy to take for granted. It isn’t until something goes wrong that we stop and realize we have no idea how this whole thing works. Here is a brief overview of the vital components that make up an HVAC system and how they affect your indoor air comfort and energy bills.


The H in HVAC stands for heating. Today property owners have many different options for their heat. The most common forced air options include gas or electric furnaces and heat pumps. Some heat pumps can even be configured to work in concert with a furnace to maximize energy savings—the furnace does the heavy lifting, but special sensors enable the heat pump to take over whenever heat output needs drop into the range this more efficient appliance can handle. As a bonus, the heat pump can also double as an air conditioner.

In order to get the best performance from your heating system, it is crucial to have a furnace or heat pump that is neither too big nor too small for your space and a programmable thermostat that can provide precision control of temperatures. The type of fuel your heater uses (gas or electric) can also have a big impact on energy-efficiency and cost.


Ventilation, or the V in HVAC, refers to the fan that circulates air inside a building as well as the ductwork and vents that enable this air to move about. In most HVAC systems, the fan or blower is actually part of the furnace. It can circulate warm air in winter and cool air in summer because it can be operated independently of the heating element.

The integrity of the ductwork is very important for HVAC efficiency, as any leaks can result in heated or cooled air escaping before it has a chance to reach its intended destination. Well-placed vents are also essential for directing air evenly to different rooms within a building.

Of course, not all buildings have ductwork. In such cases, ductless split systems can be used to deliver conditioned air from a small outdoor air conditioner or heat pump to a blower unit mounted in the wall.

Air Conditioning

There are two main ways of providing air conditioning, or the AC in HVAC, to a building. The first is with an air conditioner that is part of a split system. Split system just means that part of the air conditioner is outside and part of it is inside. The bulk of the air conditioner unit will be located outside, but the evaporator coil will be located inside. The other option is a packaged system, which is preferable in buildings were there is no room for an indoor coil. In a packaged system all of the AC components are outside in a single unit.

As with heaters, getting the right size air conditioner is very important for its efficiency and performance. An undersized AC will run constantly without producing enough air to cool the whole building evenly, while an oversized AC won’t run long enough dehumidify the air. With any type of AC unit, a variable speed fan is a very wise investment as it will help control energy costs.


In addition to the main heating, ventilation, and air conditioning components, you might want some additional accessories for your HVAC system. For example, you might want to install an air purifier to help remove airborne allergens and contaminants like dust, pet dander, mold spores, and pollen. You might also be interested in a germicidal UV lamp or a humidifier to replace lost moisture in the winter months. General Heating & Air Conditioning can perform a Home Performance evaluation and recommend the right HVAC components and accessories for your property.