How Does Air Conditioning (AC) Work? A Complete Guide

Air conditioning units — which are often part of a larger heating, ventilation, and air conditioning (HVAC) system — keep your home cool by removing heated air from inside and pushing it outside. But how does this process work?

In this guide, we’ll break it down step by step so you can better understand the refrigeration cycle, the AC parts involved, and the different types of AC systems. We’ll also cover how a home warranty can take care of AC repairs.

What Are the Different Parts of an AC?

Most central air conditioners are split systems that include indoor and outdoor components. The condenser and compressor are located outside the home, while the evaporator coil is inside, typically near the furnace or air handler. Here's an inside look at a typical air conditioner:

Related: Learn the tips and tricks to know about HVAC Maintenance to keep your system humming.

How AC Works: The Refrigeration Cycle

Air conditioners don’t create cold air. Instead, they remove heat from your house using a cycle of evaporation and condensation. Here’s how air conditioning works:

1. Evaporation (Absorbs Heat)

Warm air from inside your home blows over the evaporator coil. The coil contains refrigerant, which absorbs the heat and turns from a liquid into a gas.

2. Compression (Increases Pressure)

The refrigerant gas moves to the compressor, which squeezes it. This increases both the temperature and pressure, which prepares it to release the heat.

3. Condensation (Releases Heat)

The hot, pressurized refrigerant moves to the condenser coil outside. A fan blows over the coil and releases heat into the air. As it cools, the refrigerant turns back into a liquid.

4. Expansion (Cools Down)

The refrigerant passes through an expansion valve, which lowers its pressure and temperature. Now, it’s ready to absorb heat again, restarting the cycle.

Types of Air Conditioning Systems

There are several types of air conditioning systems, each suited for different needs:

• Central AC: Central air conditioning uses ductwork to distribute cooled air throughout an entire home. It is ideal for larger houses that require consistent cooling in multiple rooms.
• Ductless mini-split unit: This system provides targeted cooling without the need for ductwork. It is great for homes without existing ducts or for cooling specific rooms in a home.
• Window AC: A window unit is a self-contained system designed to cool a single room. It is a cost-effective option for smaller spaces or individual rooms.
• Portable AC: A portable air conditioner can be moved from room to room and vents hot air outside through a window. It is a flexible solution for temporary or supplemental cooling.
• Heat pumps: This system can both cool and heat a home by reversing the refrigeration cycle. It is an energy-efficient option for year-round climate control.

Does a Home Warranty Cover AC Repairs?

HVAC systems work hard year-round, so breakdowns can happen over time. Because air conditioning replacements can be expensive, unexpected failures can put a strain on your budget.

HVAC home warranty coverage can help take care of the cost of repairs and replacements for key HVAC components like air conditioners, heat pumps, thermostats, and ductwork. Some plans even include refrigerant recharges, which can be costly on their own.

Related: A Guide to the Types of AC Refrigerant for Your Home.

Stay Cool with AC Warranty Protection

Air conditioners work by removing heat from your home and cycling refrigerant through key components like the evaporator coil, compressor, and condenser. ACs can be part of an HVAC system that keeps your home comfortable year-round.

Since HVAC repairs can be expensive, a home warranty can help take care of repair or replacement of key AC components. If you're looking for added protection and peace of mind, get a free quote today to see how a home warranty can help.

The contents of this article are provided for general guidance only. First American Home Warranty does not assume any responsibility for losses or damages as a result of using this information.