It is understandable why many people put off repairs on certain household objects — it's often simply too much of a hassle to deal with when you have other, more pressing, things to deal with. However, unlike some household objects, a faulty air conditioner can potentially cost you more over the time if it isn't properly addressed. An example of this is improper (or nonexistent) maintenance. If you let the air conditioning coils and filters become dirty, your air conditioner will not work optimally, costing you extra money on your energy bill; additionally, the fans and compressor will become much more likely to fail before their expected lifespan has expired.
Some filters are reusable; others, however, must be replaced. Not all filters are made with equal efficiency; some will need to be replaced more regularly. As for how often your conditioning system's filter should be changed, it is recommended that they be changed every month or two during peak use. Filters may need to be replaced more frequently than this if it is experiencing heavy use.
Like most things in life, air conditioners — like your car, body, financial situation, etc. — is best served by being proactive rather than reactive. For example, a simple filter replacement is an easy task you can complete, but doing so ensures your air conditioner not only lasts longer but last longer with more efficiency.
Due to the high power required for an air conditioner to run at its peak capacity, even a small issue with the air conditioner can potentially decimate your bank account. In a commercial setting, improper air conditioner maintenance can easily cost tens of thousands of dollars, if not more for companies with large server arrays. For example, companies such as Google take the matter of cooling extremely seriously. In Google's case, failure to cool one of their server blocks can have dire ramifications for their company.
While server farms require constant cooling, households often will go many months without requiring the use of an air conditioner. Although just as applicable to perfectly functioning air conditioners, it is imperative that you keep your air conditioner well protected from dust and debris during the winter periods, where air conditioners rarely see any use. A simple way of doing this is to add a cover to the air conditioner's exterior. This is especially important for outside units, where the risk of weather, dust, and debris striking the air conditioner is greatly increased.