We need to replace our central air conditioner. What is the greenest way to go?

Asked by Alice Martinez
Hollywood, FL

Would it also qualify us for the short-term program here in Florida, cash for air-conditioner clunkers?


Andrew Michler

Answered by Andrew Michler

Masonville, CO

Baosol llc Adaptive

September 29, 2010

First have an energy auditor test your home's envelope.

  • Insulate and seal as well as you can as a first step toward an energy efficient home.
  • You may also want to check your air ducts for leakage and seal the ducts.
  • Ask an installer to calculate your cooling load after the insulation.

Once you have a good sense of the BTUs you will need, then you can hit the market for a new AC. The air conditioner's SEER rating is key: the higher the better.

  • 16 SEER is good,
  • 18 SEER is great, and
  • 21 SEER is the best you can get.

Whatever you choose, do not oversize the AC. It will simply short-cycle without removing the humidity. Many installers oversize the system, believing it will be better "just in case," but the result is poor performance, serious comfort issues from clammy air, and a high cost in energy and equipment.

For more information:

Read Steve Saunders's Q&A "My AC service contractor wants to sell me a new unit with environmentally friendly Freon. What does that mean? Should I buy it?"

Also, check Steve Saunders's answer to the question "I keep hearing that I should get a home energy audit. What should I expect to pay and expect to get?"

Tagged In: energy audit, summer energy

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