Although some types of air conditioners can be used with the doors or windows open, with a central air conditioner the building should be closed up for it to cool properly. Some central air conditioners include a heat pump, which will allow the unit to heat the home during the winter months. The main unit might be mounted on the building's roof or on the ground.
The air conditioner filter should be changed on a regular basis. This might be once a month or more frequently if the pollutants and dust levels are high. The filter may be located in the ceiling, wall, on the unit or in another location. There may be just one filter or more if it is a large central air conditioning system. A grated door usually holds the filter in place. The door will typically unscrew and swing out on hinges, and then the filter can be lifted from its place and a new filter inserted. Normally there are arrows on the filters, indicating which side should be against the opening. Filters come in a variety of sizes and should be purchased to fit the specific opening. Some filters are reusable and are cleaned instead of discarded. It is important to check with your air conditioning manufacturer to determine the appropriate filter for your system, because some filters are too dense for some systems.
When setting the temperature on your air conditioning system, set the thermostat to the desired temperature. Do not set the temperature below that number, assuming that the room will cool faster. If you want the room to get to 78 degrees F and set the room to 50 degrees F, it will get to 78 degrees F in the same amount of time as if you set the thermostat to 78 degrees F. If you set the thermostat too low and forget to reset it to a higher temperature, the unit can freeze up and cause potential problems for your unit.
Regularly maintain your unit by keeping it clean and removing any debris that has collected in or on the unit. Before attempting any maintenance, disconnect the unit from the power source. Remove leaves and debris by first opening the fan support panel. Use a dry paintbrush to dust the compressor fins on the outside of the unit. If the fins have become bent, straighten them by running a fin comb through the damaged area. Fin combs can be purchased at a hardware store. Clean the coil's condensate drain of bacteria by pouring in a bleach and water solution. At the beginning of each season the outside of the unit by the condensing unit can be hosed off with water to remove the dust and dirt. Check with your air conditioner's manufacturer on the recommended maintenance procedures for your particular unit.