What are the Major Components of an HVAC System?

Ready to become an HVAC technician? Understanding the parts of an HVAC system is one of the most important foundations of the trade. Whether you are just starting out or exploring a career change, knowing how each HVAC system component works and how they work together is essential for anyone entering the field. Once you have mastered the basics, you will be ready to enroll in an HVAC program at The Refrigeration School (RSI) in Phoenix, Arizona.

What are the Major Components of an HVAC System?

An HVAC system controls the temperature, humidity, and air quality inside a building. While systems vary by size and application, most share the same core components of an HVAC system. A solid grasp of what each part does is one of the first skills HVAC/R technicians develop on their way into the trade.

Every HVAC system is a little different, but the major parts of an HVAC system are largely consistent across residential and commercial installations. The core HVAC system components include:

Air Conditioner

The air conditioner cools a structure with a cold indoor evaporator coil, while the condenser releases hot air outside. A compressor moves refrigerant between the evaporator and condenser. The refrigerant evaporates in the indoor evaporator coil, pulling heat out of the structure and cooling the inside air.

Air Handler

The air handler is designed to heat or cool air, which is then distributed through the ventilation system to maintain a comfortable indoor temperature. It typically houses the blower motor, evaporator coil, and air filter, making it a central hub among the components of an HVAC system.

Blower Motor

After the temperature reaches a set level, an electric blower motor powers a fan pushing the warm air through the ventilation system. Blower motor issues are among the most common service calls HVAC technicians handle in residential settings.

Combustion Chamber

The combustion chamber is the location inside the furnace where fuel mixes with oxygen to produce heat. It is a critical safety component, and a cracked or failing combustion chamber can allow carbon monoxide to enter the living space, which is one reason regular furnace maintenance matters.

Condenser Coil

A component of the HVAC system that is located outside the structure where refrigerant releases the heat it absorbed from inside. The condenser coil rejects the energy from the evaporator coil to an outside source.

Evaporator Coil

Found inside the HVAC system’s indoor air handler, the evaporator coil uses refrigerant to absorb heat and lower the temperature indoors. It works in tandem with the condenser coil to complete the refrigeration cycle, making the relationship between these two coils one of the key concepts in any HVAC training program.

Heat Exchanger

A part of the furnace that absorbs heat and warms cool air when the heat of combustion rises. Like the combustion chamber, the heat exchanger is a component where cracks or failures can pose serious safety risks, making inspection skills essential for working technicians.

Heat Pump

An energy-efficient alternative to furnaces and air conditioners, heat pumps use electricity to transfer heat rather than generate it, making them one of the more efficient parts of an HVAC system available today. They can both heat and cool a space depending on the season, which makes them increasingly common in modern residential and commercial installations.

HVAC Compressor

The HVAC compressor is often called the heart of the system. It compresses the refrigerant to raise its temperature and pressure before passing it to the condenser. The five main types of HVAC compressors are:

• Reciprocating
• Rotary
• Scroll
• Screw
• Centrifugal

Refrigerant

Refrigerant is the chemical that makes the entire cooling process possible, transferring between liquid and vapor states to absorb or release heat as it moves through the system. Because many refrigerants can be harmful to the environment, the EPA requires any technician who purchases or handles refrigerants to earn Section 608 Certification. Understanding refrigerant handling is a core part of becoming a refrigeration technician..

Thermostat

A temperature sensor that decides when to turn on and off the heater or air conditioning. A smart thermostat is a Wi-Fi enabled device that can automatically heat or cool an indoor space.

Ventilation

Ventilation is the ductwork and filtration network that distributes conditioned air throughout a residence or building. It includes filters that need to be cleaned and replaced regularly to maintain air quality. Proper ventilation is also what puts the ‘V’ in HVAC, and it plays a direct role in occupant health and energy efficiency.

How Do the Parts of an HVAC System Work Together?

Understanding each component individually is important, but knowing how the parts of an HVAC system interact is what separates a beginner from a working technician. Here is a simplified overview of the cycle:

1. The thermostat detects a temperature change and signals the system to activate.
2. The blower motor moves air across the evaporator coil, where refrigerant absorbs heat and cools the air.
3. The compressor pressurizes the refrigerant and sends it to the condenser coil outside, where heat is released.
4. The air handler circulates the conditioned air through the ventilation system.
5. In heating mode, the combustion chamber, heat exchanger, and heat pump work to warm the air before it is distributed.

Want To Learn More?

Ready to start your new career at one of the best schools for HVAC in Phoenix? Because HVAC is a hands-on job, technical training is typically required for anyone to enter this field. Many people decide to invest in a trade program to learn the trade skills they need to be safe and effective as a professional. To learn more about our HVAC program offered at the Phoenix, AZ campus contact us at The Refrigeration School, or call 1-888-671-5803.