If you take care of your air conditioning unit, you could prolong its life and get the most use out of it. Generally you should be able to do most of the maintenance yourself. However, in the more serious cases, it would be better to hire a contractor.
The first and most simple step to take to prolong your air conditioner?s life is to change the filter. You should change it whenever it gets dirty. Depending on the usage, that could range from every three to six months. There are some filters out there, which can last up to a year. Ask someone in the hardware store for more tips!
Once a year be sure that you check the evaporator coil located inside the air handler to make sure there is no dust build up.
When the weather starts to cool you should check the outside of the air conditioning. You should check around the unit and make sure there is no debris on the surface of the condenser that will stop airflow. Also you should check between the fins of the condenser to see that it?s not plugged with dead bugs or pollen. Spraying the condenser with a hose will usually be good enough to get rid of all the debris.
Although many air conditioners today use direct drive motors, it is a good idea to check the belt in the air handler. You may have to replace it. If no change is required, you may only have to oil the motor bearings once a year.
It is also good to check contactors and other electrical; most of them are located inside the condensing unit. The contactor operates the compressor and the contacts get pitted and need to be replaced occasionally. Different manufacturers use different types of contactors so check the manual to find what kind you need.