types of air conditioners

Central air conditioning systems (namely ducted split systems) are the dominant forms of air conditioning in many states, but ductless mini-split systems and room (window) air conditioners are becoming increasingly popular.

These two types of air conditioners are excellent alternatives to central AC, allowing lower cooling bills. As to portable air conditioners, though increasingly popular, they are mostly supplemental devices for sporadic cooling needs.

See:

Room air conditioners
Portable Air Conditioners

Ducted AC systems

Central air conditioners are either split-systems or packaged units, and they both use supply and return ducts to circulate air.

Supply ducts carry cooled air into the home (using openings in the walls, ceilings or floors - covered by grills - technically called registers). The indoor warmer air is driven back to the central air conditioner through return ducts and their registers.

Central Packaged AC

In a packaged AC, the different parts of the system (evaporator, condenser and compressor) are all located in the same cabinet, usually placed on a roof or next to a foundation, outdoors. This outdoor located «package» is connected to the home’s interior through supply and air return ducts.

This type of air conditioners may include electric heating coils (or natural gas furnaces), which can replace a separate furnace. If you want a ducted system, and haven’t a furnace, packaged AC systems is an option you may consider.

Ducted split-systems and furnaces and air heat pumps

If your home already has a furnace or a heat pump but no air conditioner, an AC split-system is preferable to a packaged system.

In AC ducted split-systems, the air conditioner's evaporator coil is often installed in the cabinet or main supply duct of a furnace or heat pump. In other words: in most central split-system air conditioners, the indoor cabinet also contains a furnace or the indoor part of a heat pump.

Mini-splits (Ductless air conditioners)

Ductless split-systems are often known as "mini-splits", and shouldn’t be confused with central ducted split-systems.

When shopping, make sure the dealer understands which system you are referring to. There are conventional central split AC (ducted) and non-ducted split air-conditioners (mini-splits).

Mini-splits are - on their main parts - similar to central air conditioned, but instead of ducts they use a conduit that carries the refrigerant and the power, and they have a set of separated indoor air-handlers, one for each zone of the home to be cooled (some mini-plits can operate as heat pumps, providing both cooling and winter heating).

See: Mini-splits (ductless) AC: advantages and disadvantages