Have you noticed that your central AC has become inefficient over the years? This problem can potentially be caused by two coils essential to the unit's operation. There are condenser coils within the unit located outside, and evaporator coils in the main air handler located inside your home. If there are issues with either of these coils, your entire air condition may not work properly.
The Condenser Coil
Your home's air conditioning starts working with the thermostat, which sends the condenser a signal that turns on the motor inside it. Gas refrigerant is then pumped out and goes directly to the condenser coils. Condenser coils are what causes the refrigerant's phase change, causing the gas to turn into a liquid before it goes to the unit's air handler.
In order for that phase change to occur, it requires the condenser coils
Bent or broken coils should be immediately replaced because of this. A local AC installation or HVAC technician can check the coil for you, make the necessary repair, and top off refrigerant. If the coil is dirty, you could clean it yourself. All it requires is a wire brush to scrub the metal coil.
The Evaporator Coil
Liquid refrigerant leaves the condenser and heads towards the evaporator coil, traveling through the supply line that connects the two. Once it reaches the evaporator coil, another phase change occurs. Now the liquid turns to gas and heads back to your compressor. The change in phase makes the coil cold. When air passes over the coil, the air becomes cold and then gets pushed out through the vents.
If the evaporator coil is dirty, the energy efficiency of your AC unit will decrease. The coil won't get as cold and the HVAC system will have to run longer than necessary to cool down your home. It puts more wear and tear on the unit, leading to premature replacement.
You could clean this coil on your own using a foaming cleanser, which is applied directly to the coil and doesn't need to be rinsed off. Leave it on for the length of time stated on the directions, then turn the air conditioner back on again.