Home > How To Library > HVAC > Air Conditioning > EnergyWise House: Energy-Efficient Air Conditioning

EnergyWise House: Energy-Efficient Air Conditioning

Many people buy or use air conditioners without understanding their designs, components, and operating principles. Proper sizing, selection, installation, maintenance, and correct use are keys to cost-effective operation and lower overall costs.
Print VersionBookmarkEmail this page to a friend.

...Continued - Page 2 of 4 ( 1 2 3 4 )

Related Showrooms

Intelligent Warmth - The Value and Benefits of Today's Oilheat
A.I.M. Radiant Heating - Clean, Quiet, Efficient Heating
Radiantec - Radiantec Solar heating systems for home heat
Unico System - Retrofit High Performance, Heating & Air Conditioning


In a packaged central air conditioner, the evaporator, condenser, and compressor are all located in one cabinet, which usually is placed on a roof or on a concrete slab next to the house's foundation. This type of air conditioner also is used in small commercial buildings. Air supply and return ducts come from indoors through the home's exterior wall or roof to connect with the packaged air conditioner, which is usually located outdoors. Packaged air conditioners often include electric heating coils or a natural gas furnace. This combination of air conditioner and central heater eliminates the need for a separate furnace indoors.

Today's best air conditioners use 30 percent to 50 percent less energy to produce the same amount of cooling as air conditioners made in the mid 1970s. Even if your air conditioner is only 10 years old, you may save 20 percent to 40 percent of your cooling energy costs by replacing it with a newer, more efficient model.

Sizing Air Conditioners
Air conditioners are rated by the number of British Thermal Units (Btu) of heat they can remove per hour. Another common rating term for air conditioning size is the "ton," which is 12,000 Btu per hour.

How big should your air conditioner be? The size of an air conditioner depends on:
• how large your home is and how many windows it has;
• how much shade is on your home's windows, walls, and roof;
• how much insulation is in your home's ceiling and walls;
• how much air leaks into your home from the outside; and
• how much heat the occupants and appliances in your home generate.

An air conditioner's efficiency, performance, durability, and initial cost depend on matching its size to the above factors.

Make sure you buy the correct size of air conditioner. Two groups—the Air Conditioning Contractors of America (ACCA) and the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE)—publish calculation procedures for sizing central air conditioners. Reputable air conditioning contractors will use one of these procedures, often performed with the aid of a computer, to size your new central air conditioner.

Be aware that a large air conditioner will not provide the best cooling. Buying an oversized air conditioner penalizes you in the following ways. It costs more to buy a larger air conditioner than you need. The larger-than-necessary air conditioner cycles on and off more frequently, reducing its efficiency. Frequent cycling makes indoor temperatures fluctuate more and results in a less comfortable environment. Frequent cycling also inhibits moisture removal. In humid climates, removing moisture is essential for acceptable comfort. In addition, this cycling wears out the compressor and electrical parts more rapidly. Additionally, a larger air conditioner uses more electricity and creates added demands on electrical generation and delivery systems.

Air Conditioner Efficiency
Each air conditioner has an energy-efficiency rating that lists how many Btu per hour are removed for each watt of power it draws. For room air conditioners, this efficiency rating is the Energy Efficiency Ratio, or EER. For central air conditioners, it is the Seasonal Energy Efficiency Ratio, or SEER. These ratings are posted on an Energy Guide Label, which must be conspicuously attached to all new air conditioners. Many air conditioner manufacturers are participants in the voluntary EnergyStar® labeling program. EnergyStar-labeled appliances mean that they have high EER and SEER ratings.

In general, new air conditioners with higher EERs or SEERs sport higher price tags. However, the higher initial cost of an energy-efficient model will be repaid to you several times during its life span. Your utility company may encourage the purchase of a more efficient air conditioner by rebating some or all of the price difference. Buy the most efficient air conditioner you can afford, especially if you use (or think you will use) an air conditioner frequently and/or if your electricity rates are high.

...Continued - Page 2 of 4 ( 1 2 3 4 )
< Previous Page | Next Page >



Add To:
Del.icio.us
Digg
Google
Y! MyWeb
Reddit
Technorati

Find homes by zip code
Find home plans to suit your lifestyle


Bellacor.com - Quality Lighting and More


TOTO USA - Plumbing Fixtures


NewGrass - Synthetic Grass for Artificial Lawns


LightingUniverse.com - Lighting for your Home


Radiantec - Radiant Floor Heating


KnobsandHardware.com - Decorative Hardware

View all Showrooms


Related Articles Related Tips Related Videos
EnergyWise House: An Ultra Energy-Efficient Home in the Desert
Cooling Your Home Naturally
Sizing Residential Heating and Air Conditioning Systems
Microwave Savings
AC Energy Ratios
Replacing HVAC Systems
Spacepak
LP TechShield
Tyvek







 

About | FAQ | Contact | Sitemap | Privacy Policy | Terms of Use | Help
© BobVila.com 2008