A very important thing that one can do to keep your air conditioner working at maximum efficiency is to change the filter every 1-6 months.
There can be many factors that determine how often your air conditioning filter should be replaced. If you wait too long operating efficiency begins to decline, as efficiency drops operating costs increase. Changing your air filter more often than necessary is like throwing money away. Considering the cost of some filters that will add up to a lot of money over your life time.
Air conditioner filters are designed to capture a certain amount of air contaminants that float around your home, including Dust, smoke, pet hair, pollen and even bacteria. These are then trapped by a high quality air filter. However, once they reach a specific level your filter will no longer allow air to pass through the material efficiently. This creates a buildup of pressure resistance in the blower motor of the system and causes your air conditioner to work harder to do its job.