How Does Your Air Conditioning System Work?

Published on: July 6, 2012

Air conditioning and refrigeration systems use the same basic technology to cool heated air. Your home HVAC system uses a process called phase conversion to absorb heat. In this process, liquid converts to a gas through special chemicals that evaporate and condense continuously over a closed system of coils. Fans to move warm interior air over cold refrigerant coils are an important component of air conditioning systems. The ducts present in your home are essential to funneling air to and from the refrigerated coils.

Your HVAC system as three main parts: a compressor, a condenser and an evaporator. In a typical split-system air conditioning unit, the compressor and condenser are located outside, while the evaporator is inside, many times as part of the furnace.
house, sometimes as part of a furnace. That’s the part that heats your house.

The evaporator, which receives the liquid refrigerant, is known as the cold side of your air conditioning system. The condenser, with the help of a fan, blows chilled air over the coils and into your home. In between the cold and hot side is the expansion valve, which regulates the flow of the refrigerant into the evaporator. Air conditioning evaporators also have metal fins that aid in the the exchange or dissipation of heat into the surrounding air. The hot side of the HVAC system has the compressor, which is an electric pump, the condenser and another fan which moves air through your house.

Your home air conditioner also has a vent where air is sucked into the ducts and blown through the house, coming out into rooms, usually at floor level.

When warm air moves over the cold evaporator coils, refrigerant absorbs heat while it changes from a liquid to a gas. The HVAC system then converts refrigerant back to liquid, which happens through the compressor. This process creates additional, unwanted heat, which is evacuated to the outside through the condenser coils and a second fan. As the gas condenses back into a liquid, the process starts all over again. Additional sensors, timers and valves are also located here.

Your home’s thermostat, which monitors and regulates air temperature, is also a big part of the air conditioning system as it is part of the control unit which regulates the entire HVAC system operation. Cooling the air also removes much of its humidity, causing the moisture to transform from gas into liquid. Drains and moisture pans catch and disperse water discharged by air conditioners during humid periods.