How Does an HVAC System Work?

Most modern homes and buildings have efficient heating ventilation and cooling (HVAC) systems that keep people comfortable at various times of the year. It’s probably something you take for granted, but there may come a time when you want to know a little more about how these systems work. The most essential step for understanding an HVAC system is to learn about its anatomy. There are six main parts to the system:

  • Thermostat
  • Furnace
  • Evaporator coil
  • Condensing unit
  • Refrigerant lines
  • Vents

The thermostat is the control panel where you adjust your desired temperature. It measures the air temperature and it can automatically adjust the heating or air conditioning to emit either cool or warm air as needed.

Furnaces produce heat that is blown through the ductwork to heat the building. They can use a variety of different methods to produce heat such as combustion, electric resistance and solar energy.

The Evaporator coil’s purpose is to cool the air. The process of evaporation transfers heat from the air into the liquid compound inside the metal coils, which causes the air around the coils to become cooler.

The condensing unit is filled with a refrigerant in a gas state that is cooled to a liquid state, then pumped into the evaporator coils. This serves to release heat energy that was absorbed by the evaporator coil.

The Refrigerant lines carry a chemical compound in a gas state from the evaporator coil to the condenser coil where the gas is turned back into a liquid and heat is expelled from the system.

The vents are the points where warm or cool air are released into the living or working spaces of the building. They’re rectangular openings with metal slats, and they’re usually located on or near the ceiling.

Three types of HVAC systems

There are many different types of systems to control air temperature, but these are three of the most common types.

  • Split systems
  • Duct-free systems
  • Zoned systems

Split systems have components on the inside and outside of the building. They usually have a furnace, an air conditioner and ductwork to carry air throughout the building.

Duct-free systems circulate air throughout the home or building without duct work by using pipes and fans, and zoned systems allow you to set different temperatures for specific areas or rooms in the building.

If you would like to learn how HVAC systems can provide greater comfort in your building or home, don’t hesitate to call us at 408-295-2182.