Heating, ventilation, and air conditioning (HVAC) systems are what keep your home comfortable. It provides warm air in the cold and cool air in the heat, and disperses it throughout your home. Understanding the major components of your home’s HVAC system will help you better maintain it and allow you to improve your home’s energy efficiency.


The thermostat is the boss— it controls the operations of your home HVAC system. Of course, you set the controls on the thermostat, so one could argue that the thermostat is just the manager.


Your furnace is one of the main components of your HVAC system that supplies the heat to your home. The furnace works by using gas, other fuels, or electricity to warm air that passes through the furnace and is then forced into your home’s duct system.

heat exchanger

Inside every furnace is a heat exchanger, which is the component that is responsible for heating the air that enters the furnace. The heat exchanger switches on when activated by the thermostat and pulls cool are in to be warmed.

evaporator coil

While the evaporator coil is located on the furnace, it actually works for the air conditioner. Its job is the complete opposite of the heat exchanger and produces cool air.

Ventilation System

The ventilation system is the air circulation system in your home that moves warmed and cooled air throughout the house.


Ducts are the tubes or lines that line the entire house, through the ceiling and walls, to transport air from the furnace or air conditioner to vents. They are typically made of aluminum, but can be made of steel or other products.


Vents are the openings in the ductwork that allows the warmed or cooled air to be dispersed to rooms. Vents are typically placed on either the floor or the ceiling.

Air Conditioner

While all homes have ductwork and most homes have a heating unit, not all homes are equipped with an air conditioner. An air conditioner uses the same ductwork and vents as the home heating system, but has a few additional components.

condensing unit

The condensing unit is the large square box that sits outside of a house and is connected to the evaporator coil on the furnace. It is filled with refrigerant that is carried into the home to cool air that is then pumped throughout the home.

refrigerant lines

Refrigerant lines are the copper tubes that carry the refrigerant between the condensing unit and the evaporator coils.

Hot Water Heater

The hot water heater is usually located near the furnace and is a tank that holds water that it warms. The thermostats sense the temperature of the water and adjusts the heat.

Your residential HVAC system is responsible for keeping your home warmed and cooled for optimal comfort. Knowing the components of your HVAC system can help you better maintain them to prevent costly repairs or uncomfortable nights when your system suddenly stops working. If you are looking for experienced HVAC technicians in Salt Lake City, Service Mechanical Controls has you covered. Call for your free estimate today!