How Does Air Conditioning Work?



How does air conditioning work?

Part 1

The air conditioning system is designed so that refrigerant will circulate through the system,

Absorbing heat from the air flowing accross the evaporator, cooling the air down,

Then releasing that heat to the outside air flowing accross the condenser outside, which warms up that air.


How does air conditioning work?

Part 2

A compressor is used to pump the refrigerant through the system.

The refrigerant travels around the system continuously, and is never consumed or lost, unless there is a leak.


How does air conditioning work?

Part 3

The refrigerant is a fluid that researchers have found capable of evaporating and condensing at practical and usable pressures, capable of mixing with compressor lubricating oil and carrying it around the system, capable of moving heat, and safe.


How does air conditioning work?

Part 4

The refrigerant will leave the compressor and travel through the condenser at a temperature around 30 degrees higher than ambient outdoor air temperature.

This is so that the relatively cool air flowing accross the condenser will absorb heat from the refrigerant, and cause it to condense.


The refrigerant will condense because as it cools the vibrations of its molecules slow down to the point that they move close enough to each other to transform from a vapor to a liquid.

This is called a change of state, and the amount of heat energy released at this point is called the latent heat of condensation.


How does air conditioning work?

Part 5

The liquid refrigerant will now travel down the liquid line and then through the metering device.


How does air conditioning work?

Part 6

The oulet of the metering device begins the low pressure side of the refrigerant circuit, and at this point the refrigerant will begin to boil and evaporate at a low pressure and temperature, about 40 degrees F.


This point is also at the inlet to the evaporator circuit, and the refrigerant will continue to boil and evaporate as it travels through the evaporator.


How does air conditioning work?

Part 7

Relatively warm air flowing over the evaporator piping will cool down as it releases its heat content to the cold refrigerant that is evaporating in the evaporator.


How does air conditioning work?

Part 8

The refrigerant will continue to totally evaporate because as it absorbs heat and warms up the vibration of its molecules speed up to the point that they move far enough away from each other to transform from a liquid to a vapor.


This is called a change of state, and the amount of heat energy absorbed at this point is called the latent heat of evaporation.


How does air conditioning work?

Part 9

Cool air is now flowing out of the evaporator; and the refrigerant vapor, carrying the heat absorbed from that air, will return to the compressor and be pumped to the condenser, to repeat the cooling cycle until the room is cool enough to satisfy the temperature control.


How does air conditioning work?

Boiling refrigerant absorbs heat energy from air flowing over the evaporator.

The refrigerant will totally evaporate because the heat energy it absorbs will cause the vibrations of its molecules to speed up to the point that they move far enough away from each other to transform the refrigerant from its liquid state to a vapor state.

The refrigerant now travels back to the compressor, then is pumped to the condenser, where it will condense because as it releases heat to the air flowing over the condenser piping, the vibrations of its molecules will slow down to the point that the molecules move close enough together to transform the refrigerant from its vapor state to a liquid.


And this cycle is repeated until the room is cold.


There's an old saying that goes "A picture is worth a thousand words."

Our air conditioning circuit and cycle diagram page might help you understand the cycle more clearly.


I hope this page has helped, and please, feel free to contact us with any specific HVAC questions you might have, including questions about air conditioning on Guam, or refrigeration on Guam.

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