The first and most basic action to take to prolong your air conditioners life is to replace the filter. You should replace it whenever it gets dirty. Depending upon the usage, that might vary from every 3 to six months. There are some filters out there which can last up to a year. Ask someone in the hardware shop for more ideas.
Once a year, make sure that you inspect the evaporator coil found inside the air handler to make certain there is no dust build up. When the weather condition starts to cool, you should inspect the outside of the air conditioning unit. You should check around the unit and make certain there is no debris on the surface of the condenser, as that will stop air movement. Also, you should check in between the fins of the condenser to see that its not clogged with dead insects or pollen. Spraying the condenser with a hose will normally be good enough to get rid of all the particles Dallas Texas Air Conditioning Service .
Although numerous air conditioners today use direct drive motors, it is a good idea to inspect the belt in the air handler. You may have to replace it. If no change is needed, you may only have to oil the motor bearings once a year.
It is also great to inspect the contactors and various other electrical parts; many of them are found inside the condensing unit. The contactor runs the compressor, and the contacts get pitted and need to be changed occasionally. Various manufacturers utilize different kinds of contactors, so check the handbook to discover exactly what kind you need.