The air conditioner condenser coils, which sit outside the house, contain fins or coils that channel refrigerant outside the house and back into the house. It is in the condensing unit that the heat is transferred from the refrigerant (in the coils) to the outside air. This means, if the condenser isn't working properly, it will not drain away the heat, and your air conditioner's efficiency will plummet. Here are three common things that lead to malfunctioning condenser fins:

Debris on the Coils

The condenser works best when it can get the refrigerant as close to the outside air as possible. This air also needs to circulate; heated air needs to give way to cold air. Unfortunately, dirt over the condenser coils will defeat both of these purposes. Dirt acts as an insulator over the coils, preventing the free flow of air and heat. This makes the condenser operate at inefficient levels. The debris comes from debris in the air such as dust particles, leaves and grass. Therefore, you need to clean the condenser regularly to get rid of the debris and maintain its efficiency.

Malfunctioning Condenser Fan

The condenser fan is responsible for cooling the highly pressurized refrigerant so that it can be re-circulated back into the house for further cooling. It does this by blowing outside air over the condenser coils. If the fan isn't operating as usual, the refrigerant won't cool, and the operating temperature of the air conditioner will rise.

An electronic malfunction is a common cause of condenser fan failure. For example, damage to the run capacitor (which boosts the fan motor during startup) can make the fan motor, and hence the fan, malfunction. Fortunately, these capacitors are relatively cheap, and you can replace it on your own if you know your way around the air conditioner.

Damaged Coils

Coil damages usually come in two forms; they either puncture or get bent out of shape. Using excessive force (such as that from a pressure washer) or the wrong tool when cleaning the fins can damage or puncture the fins.  The same thing can happen when debris covers the coils or when the fins' material deteriorates after years of use. Bent fins restrict airflow, and ruptured fins lead to refrigerant leaks—both things lead to poor cooling.

Maintaining your air conditioner, including the outside unit, is a necessity. You can get a service contract with an HVAC company like First Class Plumbing and Heating for regular servicing or hire them each time you need the system serviced. Whichever option you choose, make sure the condenser coils aren't damaged, punctured or clogged in any way.