How Does a HVAC System Work?

HVAC systems help control the temperature in your property by offering heating and cooling solutions. But how exactly do they do this? In this blog, we’ll explain the basics of HVAC systems, so you understand how they work.

The best way to describe how these systems function is to split them up into individual parts. Each HVAC system will have the following:

  • Furnace
  • Evaporator Coil
  • Condensing Unit
  • Ducts/Vents
  • Thermostat


The furnace is the main part of your HVAC system and essentially sets everything off. It’s a huge component that’s used to heat up air. This air then gets sent through your property via ductwork/piping, where it escapes out of vents into each room. As a result, the room is heated to the desired temperature.

The type of energy source your furnace calls upon will depend on the system and your property. Some homes use solar energy to power it, while others use electricity. Either way, its sole purpose is to provide heated air for your home to enjoy.

Evaporator Coil & Condensing Unit

While the furnace does the heating work, the evaporator coil, along with the condensing unit, is responsible for cooling the temperature in your property.

The condensing unit is where the cooling process begins. In it, you will find something called refrigerant.  It’s stored in the unit as a gas but will transfer into a liquid when the condensing unit sparks into action. So, if you need to cool down your home, then refrigerant is distributed through individual pipes in its liquid form. At this point, it reaches the evaporator coil and turns back into gas form. From here, the gas is dispersed throughout your home, cooling down the ambient temperature.


The ductwork and ventilation are basically there to help distribute air through the HVAC system and into your property. You have vents in rooms that allow heated or cooled air to pass through them, altering the room temperature. With some HVAC systems, you can control which vents allow air through, meaning you can adjust the temperature in specific rooms. So, one room may be heated while the other is left cool.


Essentially, this is the brain of your HVAC system. With the thermostat, you control the temperature of your home. When you turn it up, the furnace kicks into action and warms up your property. When you drop it down, the condensing unit and evaporator coil distribute refrigerant to cool it down.

You can also use your thermostat to keep your home at the desired temperature. You program it to stay at a specific level, and your HVAC system starts working if the temperature begins to fall or climb. As a result, you have a perfectly controlled temperature in your home at all times.

When you think about it, it’s quite a simple process. Part of your HVAC system works to heat your property, while the other brings the temperature back down. If you’ve ever wondered how these systems work, then now you know!

Contact us today to schedule your air conditioning service in bucks county PA to ensure your system is up to par!