There are two main types of residential central air conditioning systems.
- Rooftop package systems usually sit on a stand on top of the roof and are connected to a sheet metal transition coming into the attic or house. Occasionally, these units will sit on the ground and the ductwork will go underneath the house or up the side of the house. These are very common with mobile homes or manufactured homes. They call it a "package" unit because all the components of a central air conditioning and heating system are located all together in one "package".
- Split systems are the most common central air conditioner used here in Phoenix and account for about 95% of all new construction. They are called "split" systems because the major components of the air conditioning and heating system are split apart and located in different parts of the house. The air handler can be located in the attic (most common), garage or inside an interior or exterior closet. The condenser is usually located outside on the ground but sometimes it is put on top of the roof if it is flat. With a split system, there are two copper lines that hold the refrigerant that runs between the air handler and the condenser.
Major components of an air conditioner:
- COMPRESSOR – The heart of the system that pumps the Freon through your coils, which cools the air. It can be compared to an engine of an automobile and it is the most costly to replace.
- EVAPORATOR COIL – Also commonly referred to as the "indoor" coil, this is the coil where the air that is circulated throughout the house gets cooled. It is very important that this coil is kept clean so there is a good exchange between the cold Freon in the coil and the air being blown across it. If the coil is dirty and/or restricted, the air will not get as cold as it should, which will cause the unit to run longer and drive utility bills up. CLEAN THAT COIL!!
- CONDENSER COIL – Also commonly referred to as the outdoor coil because it is visible on the outside of the unit, this coil releases the heat from inside the house to the outside. If this coil is dirty (and it gets dirty more often because it is outside), it can’t release the heat, which causes a strain on the compressor and the condenser fan motor and will cause them to fail or overheat. CLEAN THAT COIL!!
- METERING DEVICE/EXPANSION VALVE – This controls the flow of Freon throughout the system. This is a very critical part of the system. If the Freon has dirt or contaminants, it will cause the metering device to reduce the Freon flow and directly affect the cooling.
- BLOWER MOTOR – Also called the "indoor" fan motor, this is responsible for pulling air from the house through the filter and then through the "evaporator" coil, where the air is cooled, blown into the duct system and then into the house. If the filter is clogged or dirty, it will cause the blower motor to run under a strain and cause it to overheat or fail. CLEAN THAT COIL AND REPLACE THAT FILTER!!
- CONDENSER FAN MOTOR – Commonly called the "outdoor" fan motor, this is the hardest working motor in the entire system. It sits on top of the unit and sun beats down on it all day as it pulls very high temperature air across the outdoor coil to cool the Freon and the compressor. If this motor fails or overheats, it will immediately cause the compressor to overheat and shut off. Like the motor in your car, if the motor overheats it WILL CAUSE serious internal damage to the compressor or even cause it to fail immediately. If this motor starts showing signs of wear and tear, replace it immediately BEFORE it fails and CLEAN THAT COIL!!
SERVICE YOUR HOME’S CENTRAL A/C SYSTEM EVERY YEAR, USUALLY IN THE SPRING BEFORE THE COOLING SEASON STARTS.