More than 97% of homes in the Southern U.S. have air conditioners installed. It’s so commonplace that you may not give your air conditioner much thought until it is damaged and needs repairs.
Read on to learn about an AC unit’s five main components.
The refrigerant is a cooling fluid, also known as coolant. It is the fluid that circulates heat from your home to outside the building. This fluid moves in closed loops.
Refrigerant, also known by the brand name Freon, is the messenger for your cooling system. It picks up heat from your indoor space and travels with it to the outdoor space where it releases the heat. The fluid is special in the fact that it changes from liquid to vapor at low temperatures, and fast, to enhance the refrigeration cycle.
The fluid flows through copper coils and cooling tubes that connect the indoor and outdoor air conditioning units. The gaseous refrigerant absorbs heat from your indoor space and changes to liquid form. It flows to the outdoor AC unit from where the heat is released outdoors.
Once the fluid releases the heat, it changes back into a gaseous state and flows back indoors. When the refrigerant cools, an indoor fan blows air over the coils and that air circulates throughout your home as cold air. This cycle goes on and on as long as your air conditioner is on.
The work of a compressor is to compress or pressurize the refrigerant. This increased pressure causes an increase in the temperature of the refrigerant. The function of the compressor applies the combined gas law that says, when pressure increases, temperature increases. Compressing the refrigerant heats it up. The compressor pressurizes the refrigerant by squeezing it together.
Heating the refrigerant is important in the heat exchange between indoor and outdoor air. When the refrigerant flows outdoors, its temperature must be higher than that of outdoor air. The hotter refrigerant is then able to release heat into the hot outdoor air.
3. Condenser Coil
This is the portion of the air conditioning unit located outdoors. The unit receives the refrigerant from the indoor unit, the compressor. It works antagonistically to the evaporator coil; while the evaporator coil holds cold refrigerant, the condenser coil holds the hot refrigerant.
These coils ensure the refrigerant releases heat to the outdoors. The exchange happens with the help of a fan. A condenser fan blows the outdoor air over refrigerant coils. Heat leaves the refrigerant and goes into the outdoor air. After the heat exchange, the refrigerant turns into liquid again and flows to the expansion valve.
4. Expansion Valve
The expansion valve is responsible for cooling the refrigerant. After dispersing heat outdoors, the refrigerant changes to a liquid state. However, it is still too hot to go back indoors. If the refrigerant flowed indoors with that heat, it would heat up the home.
Also known as the metering device, the expansion valve depressurizes the fluid to lower its temperature. The process of depressurization follows the same principle of combined gas law.
As the expansion valve depressurizes the refrigerant, it changes it from liquid to vapor. The expansion valve is also responsible for controlling the amount of refrigerant that enters the evaporator. The metering of the refrigerant is dependent on your air conditioning needs.
5. Evaporator Coil
The evaporator is to the indoor exchange unit as the condenser coil is to the outdoor heat exchange unit. This is the place the refrigerant picks the hot air from your home and releases the cool air from the expansion valve.
The copper tubes inside the evaporator coil receive cold refrigerant from the expansion valve. A fan blows hot air from your indoor space over these cold coils. As this happens, the refrigerant absorbs the heat from the indoor space. The process applies the second law of thermodynamics that says heat will flow naturally from hot to cold.
The indoor air handler fan blows the air over the coils to facilitate the heat transfer. As the refrigerant absorbs heat from the indoor space, it evaporates into a vapor and flows into the condenser for pressurization.
Understanding the Refrigeration Cycle
The flow of the refrigerant, its change in state, and the heat transfer results in the cooling effect you feel in your home. Hot air is sucked from your indoor space through the return vents. The refrigerant picks the hot air as it flows over the evaporator coils, which are cold from the depressurization in the expansion valve.
As the refrigerant picks up heat from your indoor space and evaporates, the evaporated refrigerant goes into the compressor. Inside the compressor, the refrigerant is pressurized to heat it up. The hot refrigerant flows from the compressor to the condenser coils. Inside the condenser is a large and loud fan that blows outdoor air over the condenser coils.
The refrigerant flows back inside through the expansion valve. At the valve, the refrigerant undergoes depressurization to lower its temperature. From here, it flows to the evaporator coils and the process continues over again. If any of the parts is not functional, the refrigeration cycle will stop. Our technician from Rite Way Heating, Cooling & Plumbing can help you diagnose and repair the system to get it back to normal operation.
Other Minor Parts of Your Air Conditioner
The above five main components of an AC unit have help from smaller parts that make the unit complete. One of these parts is the filter, which traps particles from the indoor air before the air enters the evaporator coils. These can be made of cardboard or cotton.
As the filters trap dust and dirt, they get dirty, and you have to wash them regularly. After some time, you need to replace the filters to ensure they are functioning efficiently.
Thermostats are also part of the air conditioning system. These small units have sensors that detect and regulate the temperature of a room. Your air conditioner continues to cool a room until it reaches the desired temperature. After that, the system slows down. Once the temperature of the room rises to a certain level, the air conditioner goes back on.
The muffler is another important part. It ensures that the sound from the condenser is not uncomfortably loud. If the condenser gets noisy, you’ll know the muffler is faulty.
Another part is the drain pipes. These will drain the humidity from your indoor space to the outdoor space. The drain pipes might get clogged when dust particles from your home build up inside the pipes. You will know these pipes have issues if there is excess moisture in your rooms.
Lastly, there are two main fans in your cooling system: the blower fan inside your home and the condenser fan outside the home. These help blow air over the coils for efficient heat transfer.
Get a Free Quote From Rite Way Heating, Cooling & Plumbing Today
At Rite Way Heating, Cooling & Plumbing, we can help you with the installation, repairs, and maintenance of your heating, cooling, and plumbing systems. We ensure that your home is comfortable during every season with the help of your HVAC system. You can also call us when your air purifiers, ducts, mini-splits, and any other systems have a problem or need maintenance. We offer financing to our all of our customers. Call Rite Way Heating, Cooling & Plumbing today and request a free quote.