Air Conditioning Unit

During the hot summer months, we have all come to rely on our air conditioners for health and comfort. When air conditioning units or systems wear out, however, or need to be upgraded, it is important to understand what type and size to buy and how to proceed.

The first consideration in selecting air conditioning units is deciding if you will install a window air conditioning unit, or central air conditioning, and determine your budget--how much money you want to spend. The proper sizing and correct installation are also key elements in getting the result you are working toward. A unit that is too large for your area will not be adequate for removing humidity, and a unit that is too small will not cool the area to a comfort level during hot days. If you want to cool only one room, or two connected rooms, a window air conditioning unit may be all you need, and will save the expense of cooling the entire house. If, however, you already have duct work installed for hot air heating, and want to cool the whole house, central air conditioning may not be beyond your budget.

Window Air Conditioning Unit

For single rooms or a small area, window air conditioners are the most common choice. All parts of the unit, the evaporator and cooling coil, expansion valve, condenser and the compressor, are all closed in, usually with an aluminum shell, and the whole unit is placed in a window. For alternate installation, a slot or hole can be cut through the wall, which frees the window for continued use, but obviously it is much harder to install in that way, and that is why most people just place the unit on the window sill. Care must be taken to fasten it according to the manufacturer's instructions to avoid the danger of it falling out of the window.

If you have decided to install a window unit, first measure the area you want to cool, and then choose the BTUs needed for that size area. A BTU--British Thermal Unit--measures the output in increments of a heating or cooling device. For instance, if your room is no larger than 350 square feet, you will need 5000 to 7000 BTUs in a unit, and for a larger room, say 500 to 700 square feet, 9000 to 12000 BTUs will be needed, and so on. Also, be sure to choose a unit with the highest energy rating. Look for the Energy Star label on the unit.

Central Air Conditioning

After the main unit is installed for central air conditioning units, it will need to be connected to either existing ductwork used for heating, or ductwork will have to be installed throughout the home to reach every room. The size needed and cost of the entire system will depend on the condition and size of your home, where you live, whether you home has good insulation, ease or difficulty of the work involved, and other factors. Central systems, in general, are more efficient that window units. They are convenient, quiet and out of the way.

Hiring a reputable contractor or air conditioning specialist is the single most important decision you can make concerning acquiring central air conditioning. It is even more important than the brand of conditioner you choose. In researching for the best person to do the job, word of mouth may help, if you have friends or neighbors who have recently had this type of work done, or ask potential local contractors for referrals from their customers. Searching online will give you information on questions to ask and recommendations of what you should expect from a contractor.

Be sure you are purchasing the most energy-efficient system you can, and your contractor should be able to supply you with this information. Any air conditioner made after January 26, 2006, is required to have a SEER--Seasonal Energy Efficiency Ratio--of 13 or greater. Units with a smaller ratio rating can still be sold, so ask for the rating on your unit.

As with any purchase, save all receipts, warranties and guarantees and keep them with your important papers for as long as you own and operate the unit. If the contractor buys the unit for you from a manufacturer, ask for the receipt, or a copy, so that you know exactly where and when the central air conditioning unit and materials were purchased.