HVAC systems are the systems that keep homes warm and cozy in the winter and cool and fresh in the summer. They also help to filter indoor air and regulate humidity levels.

There are two types of HVAC systems – central and local. Central systems have primary equipment located in one location while local systems use equipment that serves a single zone.

Heating

A well-designed HVAC system can offer more than just cooling. It can warm homes in the winter and help filter and clean air to improve indoor quality.

An HVAC system can use gas furnaces or heat pumps. It can also have ducts in the home or be a ductless system for specific rooms. Regardless of the system, it will usually be powered by electricity.

When the thermostat tells the system that it’s time to heat the house, the blower motor in a gas furnace will start working. Air will be pulled in from the ductwork and blown through a heat exchanger, then heated and pushed into the space through the ducts or registers. This process can be repeated when the temperature needs to be cooled.

Cooling

A key part of an HVAC system is its ability to cool a space. It does this by moving air through a ductwork system that is connected to units like furnaces, heat pumps and air conditioners.

The cooled air is then distributed throughout the space through a network of vents, which can be controlled by a thermostat. This can be a traditional thermostat or a smart thermostat that is connected to the home’s Wi-Fi network for added convenience.

The HVAC system can be enhanced with products like air cleaners, humidifiers and dehumidifiers to control the moisture levels in a home’s air. Additionally, a smart home control system can help you improve efficiency with features like climate zones and programmable thermostats. These devices can also save you money by making small adjustments to your heating and cooling needs based on actual usage data.

Ductwork

Ductwork is the system of air ducts that transports cooled or heated air from the HVAC unit throughout your home. Well-maintained and properly insulated air ducts are essential for your heating and cooling system to work optimally.

Air ducts are made of different materials, including metal and fiberglass. Galvanized steel and aluminum are the most common types of metal used in ducts, and they’re often coated with insulation to help control their temperature.

Ducts are usually divided into sections, called terminals. Each terminal has an air flow opening known as a grille, diffuser or register. They’re located at the entrance and exit of the ducts, and they’re aided by turning vanes to direct air flow as needed.

Filters

When your system is running, air from your return ducts passes through your filter, which traps contaminants before it’s pushed into the conditioned space. Most filters have a flat panel made of spun fiberglass or another material that operates through the process of straining: Airflow causes particles to impact against the filter surface and become trapped inside.

Some of the most common HVAC service issues are due to dirty and clogged filters, which can interfere with airflow and force your system to work harder to compensate. Filters are available in a wide variety of materials and sizes, including pleated filters, which have more surface area for better trapping. Some are reusable, while others require replacement. Some have special features, such as HEPA filters, which can remove small allergens like mold spores, bacteria, and smoke.

Maintenance

A well-maintained HVAC system can save you money by reducing energy bills, improving efficiency and prolonging the life of your equipment. Regular maintenance checks can help catch problems before they cause major damage and expensive repairs.

Maintaining your system includes ensuring that the air filter is replaced regularly, keeping outdoor units clean of leaves, twigs and grass clippings and cleaning indoor vents and passages to prevent mold and dust build-up. A programmable thermostat can also lower energy costs by automatically turning on and off to match your schedule.

Many HVAC companies offer annual or bi-annual maintenance plans with varying rates, and these plans can often include priority scheduling, service discounts and repair credits. For best results, hire a company that specializes in the type of equipment you have in your home or office.