INFO: How does air conditioning work?

Last edited: 19th December 2023

How does air conditioning work?

People think that air conditioning lowers the temperature in an area by simply pumping cool air in. However, what’s really happening is that the heat from the warm air within the area to be cooled, is being removed and cycled back through the indoor unit as cooled (and possibly cleaned) air. This cycle continues until the room reaches the desired temperature, then continues to maintain the room temperature until the parameters are changed or the system is switched off.
Modern systems make use of inverter technologies to ensure the system continues to run, while using the minimum energy required, making running the system as affordable as possible!

An air conditioner is in essence, a refrigerator without the insulated box covering its parts. It uses the evaporation of a refrigerant to provide cooling or heating as required. The mechanics of the evaporation cycle are the same in a refrigerator as they are in an air conditioning unit/system.

A split system has an inside unit and an outside unit, connected via refrigerant hoses and electrical cable. The indoor unit also has a hose to take away the condensate generated during operation in cooling mode.

The great advantage of a split system (whether that’s single or multi splits) is that they are also heat pumps (most modern systems anyway) and can provide exceptional warmth to the desired area during the cooler months.
That makes air conditioning the perfect product for year round climate control, while the inverter keeps the system operating at highly economical performance levels.

How does the evaporation cycle (in an air conditioner) work?

1. The compressor compresses refrigerant which causes it to become hot and pushes the (now hot) refrigerant through a closed loop system.
2. This hot gas runs through a set of coils in the Condensor (outdoor unit) so it can dissipate its heat (to the air outside) and in doing so condenses into a liquid within the pipework.
3. This liquid runs through an expansion valve where it evaporates to become a cold low pressure gas.
4. This cold gas runs through a new set of coils in the Evaporator (inside unit) that allows the gas to absorb heat (from the air within the room) and cool down the re-circulating air.
5. The refrigerant circulates back to step 1 and the cycle repeats.

During the systems usual operation while in cooling mode, steps 1 to 3 take place within the outdoor unit and step 4 takes place within the indoor unit. To ensure the evaporation cycle performs correctly, there will always be a minimum pipe length (see manufacturers technical data for specifications) to ensure the refrigerant has time to fully change state from gas to liquid form (you can’t compress a liquid after all).

To enable the system to provide economical heating, this process is simply reversed to provide heated air (sometimes referred to as Reverse Cycle air conditioning) to the desired location.

For this type of system to operate correctly, air flow is essential for both the indoor and outdoor units. Without the correct amount of space around and in front of the units (the outside especially) the system will never reach its peak temperature capabilities in either cooling or heating modes.