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A Simple Guide to the Main Parts of Your Air Conditioning System

By April 4, 2024Air, HVAC
Parts of an air conditioning system to know

Peeling back the layers of your air conditioning system reveals more than just wires and coils – it uncovers fascinating interactions of technology and engineering, designed to keep you comfortable. This guide will take a magnifying glass to the function of a standard air conditioning system, its main parts, and the crucial maintenance necessary to keep it chugging along.

From the compressor’s silent work to the evaporator coil’s hidden role, each component plays a pivotal role in crafting the perfect indoor climate. Let’s get started on getting to know them all a bit better!

The Core Components

  • Compressor: Firstly, think of the compressor as the heart of your air conditioning system, pumping refrigerant through the system. Located in the outdoor unit, it’s vital for cooling your space. Signs of malfunction include strange noises or your AC not cooling as it should.
  • Condenser Coil: Then, a component that releases the heat from the refrigerant into the outdoor air. Found in the outdoor unit, a dirty condenser coil can lead to inefficiency and increased energy costs. Keeping it clean is crucial.
  • Evaporator Coil: Inside your home, the evaporator coil absorbs heat from the air, contributing to the cooling effect. If your rooms feel warmer than usual, it might signal issues with the evaporator coil.
  • Expansion Valve: This valve controls the flow of refrigerant into the evaporator coil, adjusting cooling power. When it malfunctions, it can lead to less efficient cooling.
  • Air Handler and Blower Unit: These components circulate air through your home. Regular cleaning can prevent airflow problems and maintain system efficiency.
  • Thermostat: The control center of your AC system, the thermostat, regulates your home’s temperature. If your AC isn’t responding correctly, the thermostat might need attention or replacement.
Main parts of an air conditioning system, excluding the external view of the outdoor unit and air handler.

Internal view of the primary components working to condition home air

Honorable Mentions

  • Filter: Also, a clean filter is essential for maintaining air quality and system efficiency. Depending on your system, you might need to clean or replace the filter every 1-3 months.
  • Ductwork: Finally, your AC system’s ductwork distributes cooled air throughout your home. Leaks or blockages can significantly reduce efficiency, leading to higher energy bills and uneven cooling.
Person performing crucial air conditioning system maintenance.

Recommended Maintenance

However, understanding your air conditioning system’s main parts is just the beginning. To ensure its longevity and efficiency, keeping up with regular maintenance is key.

  • Clean Around the Outdoor Unit: Keep the area around your outdoor unit clear of debris, leaves, and dirt. A clean surrounding allows for better airflow and system efficiency.
  • Check for Refrigerant Leaks: A system running low on refrigerant works harder, leading to increased wear and energy consumption. If you notice your system struggling to cool or frost forming on the outdoor unit, it might be time for a leak check.
  • Insulation: Lastly, ensure that your home’s insulation is in good condition. Proper insulation helps maintain indoor temperatures, reducing the workload on your air conditioning system.

Regular attention to these areas can prevent common issues, saving you from unexpected repairs and high energy bills.

When to Call a Professional

  • Poor Performance: If your system can’t keep up with cooling demands or there’s a noticeable drop in efficiency. When in times of doubt, call a pro.
  • Unusual Noises: Sounds like grinding, squealing, or banging are not typical for a healthy AC system. These noises could indicate a serious problem that needs immediate attention.
  • Refrigerant Leaks: Handling refrigerant requires specialized training and equipment. If you suspect a leak, contact a professional due to the potential health and environmental risks.


So, you’ve taken a crash course on the biggest players in your AC system. Understanding and maintaining this system is key to home comfort and efficiency. Regular care prevents issues, prolongs its life, and maintains peak performance.

Finally, while DIY maintenance is beneficial, knowing when to hire a professional is crucial. To schedule an inspection of your entire HVAC system in NH, MA, and ME, call Alpha Building Inspections today.