Is It Time For Central Air Conditioning?

Central air conditioning is a great way to make a home more comfortable during the warm season months. Air conditioning equipment is now more energy efficient and quiet than ever. If you are running one or more window AC units, switching to central air might actually reduce your energy bills.

A conventional air-conditioning system blows cooled and/or dehumidified air through ductwork to the rooms throughout the home. Typically, it employs an air handler (blower) and the existing ductwork of a forced-air furnace for cool-air delivery. Even if your home has never been fitted out for central air, or central heat, most structures can be retrofitted. Even historic homes with little room for standard ducting can be be retrofitted for central air conditioning. However, such retrofits may require opening walls, which can be very disruptive and potentially expensive to restore to the original finish. Timing the installation to coincide with a renovation project will help to reduce overall costs.

Air conditioners use the principles of refrigeration to cool the air. Modern central air units are comprised by three main parts - the compressor, the condenser and the evaporator. In a split-system AC, the compressor and condenser are combined into one unit, the part that is located outdoors. The evaporator is where the heat exchange takes place and is either utilizes an air handler or the furnace system to deliver the cool air. Many options exist for air-handling equipment placement, such as an attic, basement, crawlspace, utility closet or garage space. In a package AC system, all three components are combined into one unit and installed outdoors.

Homes can utilize the zone principle both for cooling and for heating. That is, to heat or cool only certain portions of the home as desired. It is also possible to install central air to service only, for instance, the upstairs of a home.

The equipment selected must be sized to match the space that must be cooled. Since this sort of equipment is nearly always sold and installed by the same company, they will advise you on equipment selection. Saving money on lower capacity equipment, may end costing more in the long run. An under-powered unit will be called upon to run for longer periods of time. Ultimately, a properly sized AC unit will operate more efficiently and keep your home more comfortable.

How Does an Air Conditioning System Work?

A central air conditioning system draws in air from a centrally located air return duct. The air passes through a heat-exchanger where it is cooled and dehumidified. The air is filtered and then carried back out to the rooms via the ductwork. The A/C unit is controlled by a thermostat, usually the same one that controls the heating system. The thermostat cycles the system on and off as the temperature crosses the preset temperature preferences.

Be aware that retrofitting an existing home for AC,that does not already have a furnace may not be an easy or inexpensive project. Ductwork must run from the air handler to the rooms and, to do this, must usually be routed through the attic or under the floor. Special retrofit ductwork is available. However, if your home is not suited to this type of installation, room air conditioners may be a better solution.