Air Conditioning Efficiency | ALLINONEHOMEREPAIRS247.com

Is Running Central Air Cheaper Than Running Three Wall Air Conditioners?

Air conditioning makes the hottest summer days more enjoyable, but rising energy costs and the growing awareness of energy conservation and resource depletion demands you cool your home as cheaply and energy efficiently as possible. Deciding which cooling method will save you the most - three window air conditioners or a central air unit - depends on a few factors. Cooling your home with the proper system saves you money and electricity, and keeps you completely comfortable no matter the temperature outside.

Central air units are designed to work with your heating vents to supply cool air to every room in your house. Granted, you can turn off the registers to limit or stop the air from entering a room, but the central air unit will still be running at full power. One of the ways to use a window unit, in this instance, is to spot cool a room that is occupied, but they can also save energy, be used for whole house cooling, and even during emergency power outages.

A smaller air conditioner can adequately spot cool a room where people congregate. Since even smaller central air conditioning units draw at least 15 amps or more of power, a window air conditioner that draws less energy, but can cool the room, is an effective alternative. There is no reason to cool off the entire house when only one room is occupied. You can save on energy costs and the wear and tear on your central air unit by using a window air conditioner in this instance.

Find the amperage rating of your central air conditioner and install window units that are below that rating. Cooling off the family room, the kitchen and a bedroom with three window units can save energy and be more cost effective than turning on the central air, provided the total amperage of the window units are rated less than the amperage on the central air unit. For example, window unit for a bedroom that uses 5,000 British thermal units is commonly rated at 5 amps. An 8,000 BTU unit for both the kitchen and the family room are rated at 7 amps each or 14 amps total. If the amperage draw on your central unit is 20 amps or greater, you save energy by using three window units instead.

Comparing Energy Usage

Considering that the average home uses more electricity for cooling than for any other appliance or accessory, if you want to save money on your utility bill, carefully consider your cooling choices. A central air unit uses more energy to cool your home. As Mr. Electricity states, a window unit uses anywhere from 500 to 1440 watts to run, while a 2.5 ton central unit (about the size for a typical 1,500- to 2,000-square-foot home) uses about 3,500 watts. It's not simply about the size of area cooled, but the fact that central air involves the furnace, too. The air does not flow to the rest of the house without the furnace blower - so more running parts equal a larger power draw.

Cost of Unit Installation

It's simple to see that a central unit uses more power than a window unit, but there's more to your cost than just the energy draw. Once you factor in the purchase price and cost of installation, your cost per use may rise significantly. Dividing the total price and installation labor cost by the months you use it dramatically illustrates the true cost of just having the air conditioner, without figuring in the utility bill. Window units sell for a lot less than central units, and the installation typically is do-it-yourself.

It's Not All About the Unit

Another factor when determining which cooling unit is best for your circumstances is the condition of your existing HVAC system. No matter how efficient your central air unit, if the ducts the cool air travels through are full of holes, or poorly insulated and exposed to temperature extremes, the efficiency of the whole system goes down - and the cost goes up. If you choose to run a central air unit, insulating your ducts, and inspecting and maintaining the whole system is important, although it adds to the cost. Compared with window units, which blow directly into the room and need little but occasional cleaning unless they go out, a central unit again costs more.

Verdict

Although it costs more to purchase and install a central unit - and responsible owners also spend more on annual service calls for maintenance and inspection - if you plan to cool three or more rooms, the most cost-effective and energy-efficient choice is the central unit. A central unit has greater resale value, so you recoup more of your investment if you sell your home. The weightiest factor, however, is that three window units typically use more energy than a single central unit. Also consider that three rooms likely is a large portion of the home, and every time you travel between cooling zones with a window unit, you're leaking cool air, making your unit work harder. However, neither unit will work efficiently and save money unless it is properly sized. Carefully research your choices before purchasing.