How Your Air Conditioner Works

Air conditioning is really pretty simple when you get down to the basics. It is a sealed system composed of copper tubing, some electronics, and three basic components. A compressor and two heat exchangers or coils. The cycle goes like this:

So to summarize, the air releases heat energy to the refrigerant (cooling the air) at the inside coil (evaporator) and the refrigerant releases that heat energy into the air at the outside coil (condenser).
It all boils down to hot air blowing out of the outside coil (condenser) and cool air blowing out of the inside coil (evaporator) (usually ducted to the rooms in the home).
Air conditioning is the conditioning of air within a defined space, usually a residence or a place of business. Conditioning usually involves heating or cooling, humidifying or dehumidifying, and filtering or Cleaning the Air. If you have a central air conditioner, your system cools and dehumidifies the defined space. Heating is accomplished by an add-on to the system (such as an electric heat strip) or by a seperate unit, such as a furnace.

How Your Air Conditioner Cools the Air

Central air conditioners are split system: an outdoor unit (condensing unit) and an indoor unit the air handler. The function of an air conditioner is to transport heat from one station to another. The vehicle your system uses to carry the heat is called a refrigrant, commonly referred to as Freon.
The compressor in your outdoor unit canges the refrigerant (or "Freon") into a high temperature, high pressure gas. As that gas flows through the outdoor coil, it loses heat and condenses into a high temperature, high pressure liquid. This liquid refrigerant travels through copper tubing into the evaporator coil. There the refrigerant expands. Its sudden expansion turns the refrigerant into a low temperature, low pressure gas. This gas then absorbs heat from the air circulating in the duct work. The cooled air is then distributed back through your house or place of business. Meanwhile, the heat absorbed by the refrigerant is carried back outside through copper tubing and released into the outside air.
Dirty coils and improper refrigerant levels can cause your system to cool less efficiently than it should. An inefficient system means higher energy bills. It also forces your compressor to work harder than is necessary and can actually shorten the life span of your unit. An annual air conditioning inspection by an experienced technician includes an inspection of the coils and the checking of your refrigerant charge, to insure that your system is running efficiently.

How Much Does it Take?

1 Ton of air conditioning (12,000 BTU Cooling ) for every 500 square feet of living space. 2,000 sq. ft. divided by 500 sq. ft. = about 4 Tons of A/C
This assumes some basic values, such as:

Standard 8 foot ceilings.
South facing walls are less than 20% windows.
Windows have drapes or other coverings.
Walls and attic spaces are insulated.

How Your Air Conditioner Dehumidifies the Air.
As the warm air circulating through your ducts passes over the evaporator coil, it is quickly cooled and can no longer hold as much moisture as it did at a higher temperature. The excess moisture condenses on the outside of the coils and is carried away through a drain. The process is similar to what happens when moisture condenses on the outside of a glass of ice water on a hot, humid day.
Occassionally, the drain lines may become clogged and your system will not drain properly. This can result in a drain pan overflow, leading to water leaks in your ceiling or walls. An annual air conditioning inspection by an experienced technician includes an inspection of your draining system. During the inspection, the technician will treat your draining system with an algaecide to retard the growth of algae, which can clog your system.

The Importance of a Matched System.

Your cooling system consists of an outdoor unit (thecondensing unit) and an indoor unit(air handler). These two components are designed to work together as a coordinated team to provide top performance, maximum efficiency, and comfort. Whenever you install a new outdoor unit, you should install a new, equally efficient "matched" indoor unit at the same time. While replacing the outdoor unit only may initially offer you the lowest price, it may prove more expensive over time. When your air conditioning components don't match, your system may still work, but it won't perform at the promised energy efficiency. In fact, your system could be up to 15% less efficient than stated. You may be sacrificing comfort, as well, as a mismatched system may have difficulty keeping up on the hottest days. Finally, if your cooling system's components aren't matched, it could create undue stress on your cooling system, resulting in unnecessary, premature failure.

Heat Pumps

A heat pump cools your home or place of business by extracting heat from indoor air and forcing (pumping) the heat outdoors. For diagrams and a more detailed description on how heat pumps work, visit our Heat Pumps web page.
If your home or business uses a heat pump, make sure that your heating and air conditioning technician is certified to work on heat pumps before he services your unit. Heat pumps operate on different principals than traditional furnaces and air conditioners and so are engineered differently. Not all state licensed heating and air conditioning contractors and their employees are qualified to service heat pumps. To receive heat pump certification, a technician must receive formal training in heat pump design and repair and must pass a test administered by the Refrigeration Service Engineers Society (RSES).

The Importance of an Annual Cooling Inspection

Would you drive a car year after year without ever changing the oil or taking it to a mechanic for a tune-up? Probably not. Like your car, your cooling and heating systems must be maintained in order to run efficiently and dependably. An annual cooling check-up allows a technician to identify minor problems before they become major ones.
ACU Airperforms annual cooling system inspections on both residential and commercial structures.
Click here for details on what our cooling inspection covers.