You twist a knob, turn a dial, and cool crisp air pours through the vents, a welcome relief from the sweltering heat outside. You know that it works, but do you know how it works? Surprisingly, it might not be as complicated as one might imagine.

The Most Common AC System

The most common type of system found in and around Portland is called a split system. Split systems are the most common type of central air conditioner found in the U.S.

With these systems, inside the house, tucked in a compartment, is the evaporator coil. This coil’s function is to remove heat and moisture from the air. Outside the house, a metal case contains the condenser coil, which releases that heat, and the compressor, which pumps refrigerant between the two coils.

The indoor component of the air conditioner is connected to a network of ducts, and a blower circulates the cold air through them to reach all parts of the house. This type of system is the most economical to install in a house with a central furnace, because it can share the ductwork used by the heating system.

Heat Pump Systems

Heat pumps are a variation of the traditional split system. During hot summer months, it pumps heat from the house and releases it outside. In the wintertime, it extracts heat from the outdoor air and uses it to warm the house. Because of that, heat pumps can be used effectively for both heating and cooling in mild climates. However, heat pumps do not generally work well when temperatures stay below freezing for a long time, so they are not the best choice for cold climates.

Portable and Window AC Systems

Within Portland, many homes and apartments use a minified version of the split, know as the ductless mini-split. These systems can be a good choice for houses that do not have ductwork. Like a basic split system, the ductless mini-split combines an outdoor compressor and condenser with one or more indoor air-handling units. These units are mounted high on the wall and have blowers attached. Tubing connects the indoor and outdoor units and circulates refrigerant between them. Each indoor unit is installed in a separate room and cools that room only, much like a window air conditioner.

The main advantage of ductless mini-split systems is that they can be installed without tearing up walls to install ductwork. They also allow the flow of cold air to be controlled independently in each room (or shut off altogether in empty rooms). They can also more efficient, since mini-splits avoid the energy loss associated with ductwork.

The downside is cost. Mini-splits can also be a cost effective alternative if you only want to cool certain rooms rather than a whole house, but individual room air conditioners can be still less expensive. In addition, if you are looking to cool an entire house, mini-split systems are more expensive than ducted central air conditioning systems, costing roughly 30 percent more for the same amount of cooling power.

If you’d like to know more about your particular system or need AC repair or maintenance, contact Integrity Air.