8 Tips for Buying a Central Air Conditioning System
When purchasing a new central air conditioning unit or upgrading an old one, keep several things in mind before you buy.
1. Your Home - Make sure you know the following about your home:
- Your home's square footage.
- Ductwork (Do you have it already or will you need it installed?)
- Number and location of windows. (This may affect the system you choose if your windows let in a lot of sunlight and warmth during the day.)
- Natural shading or awnings. (These may decrease your air conditioning needs.)
2. SEER (Seasonal Energy Efficiency Rating): the Department of Energy sets these rating standards for air conditioning units. A high rating indicates more energy efficiency. The lowest rating is 13.
3. How large of a an air conditioner you need: your central air conditioner needs to be the right size for your home. An undersized unit will work overtime to create the ideal temperature, while one that is too large will waste energy and increase humidity in your home. You can get a rough sense of size with our capacity calculator.
4. Climate: be sure to consider the region you live in when choosing a central air conditioner. Those living in the American Southwest would use a type made for hot dry conditions while those in the Northeast would have other needs.
5. How good is your HVAC Contractor?: things such as placement of the air conditioning unit, insulation, and duct sealing all play a role in the operation of central air. Make sure your contractor is certified and experienced in all of these areas.
6. Compatibility: when replacing an old system or adding air conditioning to an existing duct system, make sure all parts will work together efficiently. For example, an old outside compressor needs to be compatible with a new inside blower system to achieve maximum output without wasting energy.
7. Auto Off Fan: when temperatures cool down significantly, (in some desert areas, this may happen every night) you can compensate by switching your air conditioner to fan only. If this is important to you, you should be sure to choose a model with an auto-off/fan setting.
8. Cleanliness: the indoor coil of a central air conditioner attracts dust, which in turn makes the unit work harder. Keeping it clean and changing the filter regularly will save money and energy. Look for a model that is easy to clean.
Seek Expert Advice
Central air conditioners tend to cost more as their efficiency ratings (SEER) get higher. Most of them use British Thermal Units (BTUs) or tons to tell you how much air they put out. Each BTU refers to how much energy it takes to increase the temperature of a pound of water by 1 degree Fahrenheit. Twelve thousand BTUs per hour equal 1 ton, referring to how much energy it takes to melt a ton of ice in one day.
In many cases makes sense to pay a higher initial cost for a higher quality product as you will save more over the life of the system. A skilled heating, ventilating, and air conditioning (HVAC) contractor can help you determine your best option.