AC main indoor components are evaporator and filter and the outdoor components are condenser, fan and compressor. This is why most of AC systems are called split because they have two parts: indoor and outdoor.
Before introducing AC components, let's know a little about its function.
AC units use a fluid for cooling the environment called refrigerant. This fluid absorbs the heat of the room and transfers it outside. This refrigerant is always circulating to exit heat from your house or office and adjust the temperature to what is selected by the thermostat. This heat transfer cools down the internal environment.
Knowing different AC components help you better understand its function.
AC indoor unit components
Evaporator
Let's start introducing AC components with evaporator. This AC component is in charge of heat and humidity absorption from the environment. This is done with the help of the refrigerant fluid which flows inside its coils. Evaporator coils are made of copper or aluminium for the ease of heat transfer. The coils are located among some aluminium fins. Fins increase the heat exchange surface between the air and the evaporator.
Tip: most evaporators consist of U tubes sitting next to each other like a grid.
Refrigerant liquid enters the evaporator. It should first pass through the expansion valve. The expansion valve reduces the refrigerant pressure so its boiling point comes down and cools down faster. The refrigerant leaving the expansion valve is pretty cold and boiling. So, it can absorb the environment heat.
AC internal fan blows the hot air over the fins and coils. So, the refrigerant can absorb the heat.
Air filter
Air filer is one of the AC components located in the indoor unit. It cleans the air suctioned into the air conditioner unit. If there isn't any filter, dust and contamination can rapidly sit on the AC components especially internal unit coil fins. So, the AC productivity decreases.
Tip: air filters are washable and permanent in some ACs but they are replaceable in most of them.
AC outdoor unit components
Compressor
Refrigerant liquid turns into vapour after absorbing heat in evaporator. This vapour passes through one of the most important AC components which is the compressor and heats up. Now it's ready to lose its heat. In fact, compressor compresses the refrigerant as its name indicates and turns it into a high-pressure gas, sends it into condenser coils.
Condenser
This AC component is located inside a big box outside the house. There are other AC components in the box too, such as service valves, accumulator, capillary tube, etc.
The AC components related to the condenser are coils, fins and fan.
The hot and high-pressure refrigerant gas leaving the compressor enters condenser and releases most of the heat it has absorbed inside the house. The outdoor unit fan blows the air over the fins and coils in order to help the refrigerant lose its heat.
The high number of condenser fins and coils increase the time of refrigerant exposure to air in order for losing its heat. So, the hot refrigerant gas turns into a cold liquid and returns inside the house.
Tip: evaporator and condenser coils are both heat exchangers, working opposite of each other. Condenser coils help the refrigerant lose its heat and evaporator coils help it absorb the heat.
Fan
Both indoor and outdoor units have this AC component. Their duty in both units is moving the air and flowing it over the evaporator and condenser fins to increase the speed of heat exchange between the coils and the air.
- Indoor unit fan
The hot air of the house indoor environment is led towards the evaporator with the help of a fan. The air loses its heat there, and flows back to the room.
- Outdoor unit fan
The temperature of the condenser increases because of the hot refrigerant entering it. So, the fan duty is moving the air to send this heat from condenser coils to the outdoor environment. Then the refrigerant cools down and is condensed
Tip: outdoor unit fans are axial and indoor unit fans are radial.
Now that you know all the five main AC components, let's point to another AC component which is located between the condenser and evaporator. Expansion valve which we mentioned in evaporator part, controls and adjusts the amount of refrigerant into the evaporator and also decreases the refrigerant pressure.
Tip: the refrigerant type for AC units is usually R410A and R22.
If you need more information about air conditioners, you can watch our air conditioner instructional video in HelloTechnic training system. Our experts have thought every detailed information about AC function, installation, service and repair to turn you into a professional repairman.
